Exemplarische Vorgehensweise: Erstellen eines benutzerdefinierten Textvorlagenhosts

Ein Textvorlagenhost stellt eine Umgebung bereit, die die Ausführung des Textvorlagen-Transformationsmoduls ermöglicht. Der Host ist für die Verwaltung der Interaktion des Moduls mit dem Dateisystem zuständig. Wenn das Modul oder der Direktivenprozessor eine Datei oder eine Assembly benötigen, können sie eine Ressource vom Host anfordern. Der Host kann dann Verzeichnisse und den globalen Assemblycache nach der angeforderten Ressource durchsuchen. Weitere Informationen finden Sie unter Textvorlagen-Transformationsprozess.

Sie können einen benutzerdefinierten Host schreiben, wenn Sie die Textvorlagen-Transformationsfunktionalität von außerhalb von Visual Studio verwenden möchten, oder wenn Sie die Funktion in benutzerdefinierte Tools integrieren möchten. Zum Erstellen eines benutzerdefinierten Hosts müssen Sie eine Klasse erstellen, die von ITextTemplatingEngineHost erbt. Die Dokumentation der einzelnen Methoden finden Sie unter ITextTemplatingEngineHost.

Warnung

Wenn Sie eine Visual Studio-Erweiterung oder ein -Paket schreiben, verwenden Sie ggf. den Textvorlagendienst, anstatt einen eigenen Host zu erstellen. Weitere Informationen finden Sie unter Aufrufen von Texttransformation in einer VS-Erweiterung.

In dieser exemplarischen Vorgehensweise werden u. a. die folgenden Aufgaben beschrieben:

  • Erstellen eines benutzerdefinierten Textvorlagenhosts

  • Testen des benutzerdefinierten Hosts

Vorbereitungsmaßnahmen

Zum Durchführen dieser exemplarischen Vorgehensweise benötigen Sie Folgendes:

  • Visual Studio 2010

  • Visual Studio 2010 SDK

Erstellen eines benutzerdefinierten Textvorlagenhosts

In dieser exemplarischen Vorgehensweise erstellen Sie einen benutzerdefinierten Host in einer ausführbaren Anwendung, die über die Befehlszeile aufgerufen werden kann. Die Anwendung akzeptiert eine Textvorlagendatei als Argument, liest die Vorlage, ruft das Modul zum Transformieren der Vorlage auf und zeigt aufgetretene Fehler im Eingabeaufforderungsfenster an.

So erstellen Sie einen benutzerdefinierten Host

  1. Erstellen Sie in Visual Studio eine neue Visual Basic- oder C#-Konsolenanwendung mit dem Namen "CustomHost".

  2. Fügen Sie einen Verweis auf die folgenden Assemblys hinzu:

    • Microsoft.VisualStudio.TextTemplating.10.0

    • Microsoft.VisualStudio.TextTemplating.Interfaces.10.0

  3. Ersetzen Sie den Code in der Datei "Program.cs" oder "Module1.vb" durch folgenden Code:

    using System;
    using System.IO;
    using System.CodeDom.Compiler;
    using System.Collections.Generic;
    using System.Text;
    using Microsoft.VisualStudio.TextTemplating;
    
    namespace CustomHost
    {
        //The text template transformation engine is responsible for running 
        //the transformation process.
        //The host is responsible for all input and output, locating files, 
        //and anything else related to the external environment.
        //-------------------------------------------------------------------------
        class CustomCmdLineHost : ITextTemplatingEngineHost
        {
            //the path and file name of the text template that is being processed
            //---------------------------------------------------------------------
            internal string TemplateFileValue;
            public string TemplateFile
            {
                get { return TemplateFileValue; }
            }
            //This will be the extension of the generated text output file.
            //The host can provide a default by setting the value of the field here.
            //The engine can change this value based on the optional output directive
            //if the user specifies it in the text template.
            //---------------------------------------------------------------------
            private string fileExtensionValue = ".txt";
            public string FileExtension
            {
                get { return fileExtensionValue; }
            }
            //This will be the encoding of the generated text output file.
            //The host can provide a default by setting the value of the field here.
            //The engine can change this value based on the optional output directive
            //if the user specifies it in the text template.
            //---------------------------------------------------------------------
            private Encoding fileEncodingValue = Encoding.UTF8;
            public Encoding FileEncoding
            {
                get { return fileEncodingValue; }
            }
            //These are the errors that occur when the engine processes a template.
            //The engine passes the errors to the host when it is done processing,
            //and the host can decide how to display them. For example, the host 
            //can display the errors in the UI or write them to a file.
            //---------------------------------------------------------------------
            private CompilerErrorCollection errorsValue;
            public CompilerErrorCollection Errors
            {
                get { return errorsValue; }
            }
            //The host can provide standard assembly references.
            //The engine will use these references when compiling and
            //executing the generated transformation class.
            //--------------------------------------------------------------
            public IList<string> StandardAssemblyReferences
            {
                get
                {
                    return new string[]
                    {
                        //If this host searches standard paths and the GAC,
                        //we can specify the assembly name like this.
                        //---------------------------------------------------------
                        //"System"
    
                        //Because this host only resolves assemblies from the 
                        //fully qualified path and name of the assembly,
                        //this is a quick way to get the code to give us the
                        //fully qualified path and name of the System assembly.
                        //---------------------------------------------------------
                        typeof(System.Uri).Assembly.Location
                    };
                }
            }
            //The host can provide standard imports or using statements.
            //The engine will add these statements to the generated 
            //transformation class.
            //--------------------------------------------------------------
            public IList<string> StandardImports
            {
                get
                {
                    return new string[]
                    {
                        "System"
                    };
                }
            }
            //The engine calls this method based on the optional include directive
            //if the user has specified it in the text template.
            //This method can be called 0, 1, or more times.
            //---------------------------------------------------------------------
            //The included text is returned in the context parameter.
            //If the host searches the registry for the location of include files,
            //or if the host searches multiple locations by default, the host can
            //return the final path of the include file in the location parameter.
            //---------------------------------------------------------------------
            public bool LoadIncludeText(string requestFileName, out string content, out string location)
            {
                content = System.String.Empty;
                location = System.String.Empty;
    
                //If the argument is the fully qualified path of an existing file,
                //then we are done.
                //----------------------------------------------------------------
                if (File.Exists(requestFileName))
                {
                    content = File.ReadAllText(requestFileName);
                    return true;
                }
                //This can be customized to search specific paths for the file.
                //This can be customized to accept paths to search as command line
                //arguments.
                //----------------------------------------------------------------
                else
                {
                    return false;
                }
            }
            //Called by the Engine to enquire about 
            //the processing options you require. 
            //If you recognize that option, return an 
            //appropriate value. 
            //Otherwise, pass back NULL.
            //--------------------------------------------------------------------
            public object GetHostOption(string optionName)
            {
            object returnObject;
            switch (optionName)
            {
            case "CacheAssemblies":
                        returnObject = true;
         break;
            default:
            returnObject = null;
            break;
            }
            return returnObject;
            }
            //The engine calls this method to resolve assembly references used in
            //the generated transformation class project and for the optional 
            //assembly directive if the user has specified it in the text template.
            //This method can be called 0, 1, or more times.
            //---------------------------------------------------------------------
            public string ResolveAssemblyReference(string assemblyReference)
            {
                //If the argument is the fully qualified path of an existing file,
                //then we are done. (This does not do any work.)
                //----------------------------------------------------------------
                if (File.Exists(assemblyReference))
                {
                    return assemblyReference;
                }
                //Maybe the assembly is in the same folder as the text template that 
                //called the directive.
                //----------------------------------------------------------------
                string candidate = Path.Combine(Path.GetDirectoryName(this.TemplateFile), assemblyReference);
                if (File.Exists(candidate))
                {
                    return candidate;
                }
                //This can be customized to search specific paths for the file
                //or to search the GAC.
                //----------------------------------------------------------------
                //This can be customized to accept paths to search as command line
                //arguments.
                //----------------------------------------------------------------
                //If we cannot do better, return the original file name.
                return "";
            }
            //The engine calls this method based on the directives the user has 
            //specified in the text template.
            //This method can be called 0, 1, or more times.
            //---------------------------------------------------------------------
            public Type ResolveDirectiveProcessor(string processorName)
            {
                //This host will not resolve any specific processors.
                //Check the processor name, and if it is the name of a processor the 
                //host wants to support, return the type of the processor.
                //---------------------------------------------------------------------
                if (string.Compare(processorName, "XYZ", StringComparison.OrdinalIgnoreCase) == 0)
                {
                    //return typeof();
                }
                //This can be customized to search specific paths for the file
                //or to search the GAC
                //If the directive processor cannot be found, throw an error.
                throw new Exception("Directive Processor not found");
            }
            //A directive processor can call this method if a file name does not 
            //have a path.
            //The host can attempt to provide path information by searching 
            //specific paths for the file and returning the file and path if found.
            //This method can be called 0, 1, or more times.
            //---------------------------------------------------------------------
            public string ResolvePath(string fileName)
            {
                if (fileName == null)
                {
                    throw new ArgumentNullException("the file name cannot be null");
                }
                //If the argument is the fully qualified path of an existing file,
                //then we are done
                //----------------------------------------------------------------
                if (File.Exists(fileName))
                {
                    return fileName;
                }
                //Maybe the file is in the same folder as the text template that 
                //called the directive.
                //----------------------------------------------------------------
                string candidate = Path.Combine(Path.GetDirectoryName(this.TemplateFile), fileName);
                if (File.Exists(candidate))
                {
                    return candidate;
                }
                //Look more places.
                //----------------------------------------------------------------
                //More code can go here...
                //If we cannot do better, return the original file name.
                return fileName;
            }
            //If a call to a directive in a text template does not provide a value
            //for a required parameter, the directive processor can try to get it
            //from the host by calling this method.
            //This method can be called 0, 1, or more times.
            //---------------------------------------------------------------------
            public string ResolveParameterValue(string directiveId, string processorName, string parameterName)
            {
                if (directiveId == null)
                {
                    throw new ArgumentNullException("the directiveId cannot be null");
                }
                if (processorName == null)
                {
                    throw new ArgumentNullException("the processorName cannot be null");
                }
                if (parameterName == null)
                {
                    throw new ArgumentNullException("the parameterName cannot be null");
                }
                //Code to provide "hard-coded" parameter values goes here.
                //This code depends on the directive processors this host will interact with.
                //If we cannot do better, return the empty string.
                return String.Empty;
            }
            //The engine calls this method to change the extension of the 
            //generated text output file based on the optional output directive 
            //if the user specifies it in the text template.
            //---------------------------------------------------------------------
            public void SetFileExtension(string extension)
            {
                //The parameter extension has a '.' in front of it already.
                //--------------------------------------------------------
                fileExtensionValue = extension;
            }
            //The engine calls this method to change the encoding of the 
            //generated text output file based on the optional output directive 
            //if the user specifies it in the text template.
            //----------------------------------------------------------------------
            public void SetOutputEncoding(System.Text.Encoding encoding, bool fromOutputDirective)
            {
                fileEncodingValue = encoding;
            }
            //The engine calls this method when it is done processing a text
            //template to pass any errors that occurred to the host.
            //The host can decide how to display them.
            //---------------------------------------------------------------------
            public void LogErrors(CompilerErrorCollection errors)
            {
                errorsValue = errors;
            }
            //This is the application domain that is used to compile and run
            //the generated transformation class to create the generated text output.
            //----------------------------------------------------------------------
            public AppDomain ProvideTemplatingAppDomain(string content)
            {
                //This host will provide a new application domain each time the 
                //engine processes a text template.
                //-------------------------------------------------------------
                return AppDomain.CreateDomain("Generation App Domain");
                //This could be changed to return the current appdomain, but new 
                //assemblies are loaded into this AppDomain on a regular basis.
                //If the AppDomain lasts too long, it will grow indefintely, 
                //which might be regarded as a leak.
                //This could be customized to cache the application domain for 
                //a certain number of text template generations (for example, 10).
                //This could be customized based on the contents of the text 
                //template, which are provided as a parameter for that purpose.
            }
        }
        //This will accept the path of a text template as an argument.
        //It will create an instance of the custom host and an instance of the
        //text templating transformation engine, and will transform the
        //template to create the generated text output file.
        //-------------------------------------------------------------------------
        class Program
        {
            static void Main(string[] args)
            {
                try
                {
                    ProcessTemplate(args);
                }
                catch (Exception ex)
                {
                    Console.WriteLine(ex.Message);
                }
            }
            static void ProcessTemplate(string[] args)
            {
                string templateFileName = null;
                if (args.Length == 0)
                {
                    throw new System.Exception("you must provide a text template file path");
                }
                templateFileName = args[0];
                if (templateFileName == null)
                {
                    throw new ArgumentNullException("the file name cannot be null");
                }
                if (!File.Exists(templateFileName))
                {
                    throw new FileNotFoundException("the file cannot be found");
                }
                CustomCmdLineHost host = new CustomCmdLineHost();
                Engine engine = new Engine();
                host.TemplateFileValue = templateFileName;
                //Read the text template.
                string input = File.ReadAllText(templateFileName);
                //Transform the text template.
                string output = engine.ProcessTemplate(input, host);
                string outputFileName = Path.GetFileNameWithoutExtension(templateFileName);
                outputFileName = Path.Combine(Path.GetDirectoryName(templateFileName), outputFileName);
                outputFileName = outputFileName + "1" + host.FileExtension;
                File.WriteAllText(outputFileName, output, host.FileEncoding);
    
                foreach (CompilerError error in host.Errors)
                {
                    Console.WriteLine(error.ToString());
                }
            }
        }
    }
    
    Imports System
    Imports System.IO
    Imports System.CodeDom.Compiler
    Imports System.Collections.Generic
    Imports System.Text
    Imports Microsoft.VisualStudio.TextTemplating
    
    Namespace CustomHost
        'The text template transformation engine is responsible for running 
        'the transformation process.
        'The host is responsible for all input and output, locating files, 
        'and anything else related to the external environment.
        '-------------------------------------------------------------------------
        Public Class CustomCmdLineHost
            Implements ITextTemplatingEngineHost
    
            'the path and file name of the text template that is being processed
            '---------------------------------------------------------------------
            Friend TemplateFileValue As String
            Public ReadOnly Property TemplateFile() As String Implements ITextTemplatingEngineHost.TemplateFile
                Get
                    Return TemplateFileValue
                End Get
            End Property
            'This will be the extension of the generated text output file.
            'The host can provide a default by setting the value of the field here.
            'The engine can change this based on the optional output directive
            'if the user specifies it in the text template.
            '---------------------------------------------------------------------
            Private fileExtensionValue As String = ".txt"
            Public ReadOnly Property FileExtension() As String
                Get
                    Return fileExtensionValue
                End Get
            End Property
            'This will be the encoding of the generated text output file.
            'The host can provide a default by setting the value of the field here.
            'The engine can change this value based on the optional output directive
            'if the user specifies it in the text template.
            '---------------------------------------------------------------------
            Private fileEncodingValue As Encoding = Encoding.UTF8
            Public ReadOnly Property fileEncoding() As Encoding
                Get
                    Return fileEncodingValue
                End Get
            End Property
            'These are the errors that occur when the engine processes a template.
            'The engine passes the errors to the host when it is done processing,
            'and the host can decide how to display them. For example, the host 
            'can display the errors in the UI or write them to a file.
            '---------------------------------------------------------------------
            Private errorsValue As CompilerErrorCollection
            Public ReadOnly Property Errors() As CompilerErrorCollection
                Get
                    Return errorsValue
                End Get
            End Property
            'The host can provide standard assembly references.
            'The engine will use these references when compiling and
            'executing the generated transformation class.
            '--------------------------------------------------------------
            Public ReadOnly Property StandardAssemblyReferences() As IList(Of String) Implements ITextTemplatingEngineHost.StandardAssemblyReferences
                Get
                    'If this host searches standard paths and the GAC,
                    'we can specify the assembly name like this.
                    '---------------------------------------------------------
                    'Return New String() {"System"}
                    'Because this host only resolves assemblies from the 
                    'fully qualified path and name of the assembly,
                    'this is a quick way to get the code to give us the
                    'fully qualified path and name of the System assembly.
                    '---------------------------------------------------------
                    Return New String() {(New System.UriBuilder()).GetType().Assembly.Location}
                End Get
            End Property
            'The host can provide standard imports or imports statements.
            'The engine will add these statements to the generated 
            'transformation class.
            '--------------------------------------------------------------
            Public ReadOnly Property StandardImports() As IList(Of String) Implements ITextTemplatingEngineHost.StandardImports
                Get
                    Return New String() {"System"}
                End Get
            End Property
            ' Called by the Engine to enquire about 
            ' the processing options you require. 
            ' If you recognize that option, return an 
            ' appropriate value. 
            ' Otherwise, pass back NULL.
            '--------------------------------------------------------------------
            Public Function GetHostOption(ByVal optionName As String) As Object Implements ITextTemplatingEngineHost.GetHostOption
                Dim returnObject As Object
                Select Case optionName
                    Case "CacheAssemblies"
                        returnObject = True
                    Case Else
                        returnObject = False
                End Select
                Return returnObject
            End Function
            'The engine calls this method based on the optional include directive
            'if the user has specified it in the text template.
            'This method can be called 0, 1, or more times.
            '---------------------------------------------------------------------
            'The included text is returned in the context parameter.
            'If the host searches the registry for the location of include files
            'or if the host searches multiple locations by default, the host can
            'return the final path of the include file in the location parameter.
            '---------------------------------------------------------------------
            Public Function LoadIncludeText(ByVal requestFileName As String, ByRef content As String, ByRef location As String) As Boolean Implements ITextTemplatingEngineHost.LoadIncludeText
                content = System.String.Empty
                location = System.String.Empty
                'If the argument is the fully qualified path of an existing file,
                'then we are done.
                '----------------------------------------------------------------
                If File.Exists(requestFileName) Then
                    content = File.ReadAllText(requestFileName)
                    Return True
                'This can be customized to search specific paths for the file.
                'This can be customized to accept paths to search as command line
                'arguments.
                '----------------------------------------------------------------
                Else
                    Return False
                End If
            End Function
            'The engine calls this method to resolve assembly references used in
            'the generated transformation class project and for the optional 
            'assembly directive if the user has specified it in the text template.
            'This method can be called 0, 1, or more times.
            '---------------------------------------------------------------------
            Public Function ResolveAssemblyReference(ByVal assemblyReference As String) As String Implements ITextTemplatingEngineHost.ResolveAssemblyReference
                'If the argument is the fully qualified path of an existing file,
                'then we are done. (This does not do any work.)
                '----------------------------------------------------------------
                If File.Exists(assemblyReference) Then
                    Return assemblyReference
                End If
                'Maybe the assembly is in the same folder as the text template that 
                'called the directive.
                '----------------------------------------------------------------
                Dim candidate As String = Path.Combine(Path.GetDirectoryName(Me.TemplateFile), assemblyReference)
                If File.Exists(candidate) Then
                    Return candidate
                End If
                'This can be customized to search specific paths for the file,
                'or to search the GAC.
                '----------------------------------------------------------------
                'This can be customized to accept paths to search as command line
                'arguments.
                '----------------------------------------------------------------
                'If we cannot do better, return the original file name.
                Return ""
            End Function
            'The engine calls this method based on the directives the user has 
            'specified in the text template.
            'This method can be called 0, 1, or more times.
            '---------------------------------------------------------------------
            Public Function ResolveDirectiveProcessor(ByVal processorName As String) As System.Type Implements ITextTemplatingEngineHost.ResolveDirectiveProcessor
                'This host will not resolve any specific processors.
                'Check the processor name, and if it is the name of a processor the 
                'host wants to support, return the type of the processor.
                '---------------------------------------------------------------------
                If String.Compare(processorName, "XYZ", StringComparison.InvariantCultureIgnoreCase) = 0 Then
                    'return typeof()
                End If
                'This can be customized to search specific paths for the file,
                'or to search the GAC.
                'If the directive processor cannot be found, throw an error.
                Throw New Exception("Directive Processor not found")
            End Function
            'A directive processor can call this method if a file name does not 
            'have a path.
            'The host can attempt to provide path information by searching 
            'specific paths for the file and returning the file and path if found.
            'This method can be called 0, 1, or more times.
            '---------------------------------------------------------------------
            Public Function ResolvePath(ByVal fileName As String) As String Implements ITextTemplatingEngineHost.ResolvePath
                If fileName Is Nothing Then
                    Throw New ArgumentNullException("the file name cannot be null")
                End If
                'If the argument is the fully qualified path of an existing file,
                'then we are done.
                '----------------------------------------------------------------
                If File.Exists(fileName) Then
                    Return fileName
                End If
                'Maybe the file is in the same folder as the text template that 
                'called the directive.
                '----------------------------------------------------------------
                Dim candidate As String = Path.Combine(Path.GetDirectoryName(Me.TemplateFile), fileName)
                If File.Exists(candidate) Then
                    Return candidate
                End If
                'Look more places.
                '----------------------------------------------------------------
                'More code can go here...
                'If we cannot do better, return the original file name
                Return fileName
            End Function
            'If a call to a directive in a text template does not provide a value
            'for a required parameter, the directive processor can try to get it
            'from the host by calling this method.
            'This method can be called 0, 1, or more times.
            '---------------------------------------------------------------------
            Public Function ResolveParameterValue(ByVal directiveId As String, ByVal processorName As String, ByVal parameterName As String) As String Implements ITextTemplatingEngineHost.ResolveParameterValue
                If directiveId Is Nothing Then
                    Throw New ArgumentNullException("the directiveId cannot be null")
                End If
                If processorName Is Nothing Then
                    Throw New ArgumentNullException("the processorName cannot be null")
                End If
                If parameterName Is Nothing Then
                    Throw New ArgumentNullException("the parameterName cannot be null")
                End If
                'Code to provide "hard-coded" parameter values goes here.
                'This code depends on the directive processors this host will interact with.
                'If we cannot do better, return the empty string.
                Return String.Empty
            End Function
            'The engine calls this method to change the extension of the 
            'generated text output file based on the optional output directive 
            'if the user specifies it in the text template.
            '---------------------------------------------------------------------
            Public Sub SetFileExtension(ByVal extension As String) Implements ITextTemplatingEngineHost.SetFileExtension
                'The parameter extension has a '.' in front of it already.
                '--------------------------------------------------------
                fileExtensionValue = extension
            End Sub
            'The engine calls this method to change the encoding of the 
            'generated text output file based on the optional output directive 
            'if the user specifies it in the text template.
            '---------------------------------------------------------------------
            Public Sub SetOutputEncoding(ByVal encoding As System.Text.Encoding, ByVal fromOutputDirective As Boolean) Implements ITextTemplatingEngineHost.SetOutputEncoding
                fileEncodingValue = encoding
            End Sub
            'The engine calls this method when it is done processing a text
            'template to pass any errors that occurred to the host.
            'The host can decide how to display them.
            '---------------------------------------------------------------------
            Public Sub LogErrors(ByVal errors As System.CodeDom.Compiler.CompilerErrorCollection) Implements ITextTemplatingEngineHost.LogErrors
                errorsValue = errors
            End Sub
            'This is the application domain that is used to compile and run
            'the generated transformation class to create the generated text output.
            '----------------------------------------------------------------------
            Public Function ProvideTemplatingAppDomain(ByVal content As String) As System.AppDomain Implements ITextTemplatingEngineHost.ProvideTemplatingAppDomain
                'This host will provide a new application domain each time the 
                'engine processes a text template.
                '-------------------------------------------------------------
                Return AppDomain.CreateDomain("Generation App Domain")
                'This could be changed to return the current appdomain, but new 
                'assemblies are loaded into this AppDomain on a regular basis.
                'If the AppDomain lasts too long, it will grow indefintely, 
                'which might be regarded as a leak.
                'This could be customized to cache the application domain for 
                'a certain number of text template generations (for example, 10).
                'This could be customized based on the contents of the text 
                'template, which are provided as a parameter for that purpose.
            End Function
        End Class 'CustomCmdLineHost
        'This will accept the path of a text template as an argument.
        'It will create an instance of the custom host and an instance of the
        'text templating transformation engine. It will also transform the
        'template to create the generated text output file.
        '-------------------------------------------------------------------------
        Class Program
            Shared Sub Main(ByVal args As String())
                Try
                    ProcessTemplate(args)
                Catch ex As Exception
                    Console.WriteLine(ex.Message)
                End Try
            End Sub
            Shared Sub ProcessTemplate(ByVal args As String())
                Dim templateFileName As String = ""
                If args.Length = 0 Then
                    Throw New System.Exception("you must provide a text template file path")
                End If
                templateFileName = args(0)
                If templateFileName Is Nothing Then
                    Throw New ArgumentNullException("the file name cannot be null")
                End If
                If Not File.Exists(templateFileName) Then
                    Throw New FileNotFoundException("the file cannot be found")
                End If
                Dim host As CustomCmdLineHost = New CustomCmdLineHost()
                Dim engine As Engine = New Engine()
                host.TemplateFileValue = templateFileName
                'Read the text template.
                Dim input As String = File.ReadAllText(templateFileName)
                'Transform the text template.
                Dim output As String = engine.ProcessTemplate(input, host)
                Dim outputFileName As String = Path.GetFileNameWithoutExtension(templateFileName)
                outputFileName = Path.Combine(Path.GetDirectoryName(templateFileName), outputFileName)
                outputFileName = outputFileName & "1" & host.FileExtension
                File.WriteAllText(outputFileName, output, host.fileEncoding)
                Dim e As CompilerError
                For Each e In host.Errors
                    Console.WriteLine(e.ToString())
                Next
            End Sub 'ProcessTemplate
        End Class 'Program
    End Namespace
    
  4. Öffnen Sie im Fall eines Visual Basic-Projekts das Menü Projekt, und klicken Sie auf CustomHost-Eigenschaften. Klicken Sie in der Liste Startobjekt auf CustomHost.Program.

  5. Klicken Sie im Menü Datei auf Alle speichern.

  6. Klicken Sie im Menü Erstellen auf Projektmappe erstellen.

Testen des benutzerdefinierten Hosts

Zum Testen des benutzerdefinierten Hosts schreiben Sie eine Textvorlage. Anschließend führen Sie den benutzerdefinierten Host aus, übergeben den Namen der Textvorlage an den Host und überprüfen, ob die Vorlage transformiert wird.

So erstellen Sie eine Textvorlage zum Testen des benutzerdefinierten Hosts

  1. Erstellen Sie eine Textdatei mit dem Namen TestTemplate.tt.

    Sie können einen beliebigen Text-Editor (z. B. Editor) zum Erstellen der Datei verwenden.

  2. Fügen Sie der Datei die folgende Zeile hinzu:

    Tipp

    Die Programmiersprache der Textvorlage muss nicht mit der Sprache des benutzerdefinierten Hosts identisch sein.

    Text Template Host Test
    
    <#@ template debug="true" #>
    
    <# //Uncomment this line to test that the host allows the engine to set the extension. #>
    <# //@ output extension=".htm" #>
    
    <# //Uncomment this line if you want to debug the generated transformation class. #>
    <# //System.Diagnostics.Debugger.Break(); #>
    
    <# for (int i=0; i<3; i++)
       {
           WriteLine("This is a test");
       } 
    #>
    
    Text Template Host Test
    
    <#@ template debug="true" language="VB"#>
    
    <# 'Uncomment this line to test that the host allows the engine to set the extension. #>
    <# '@ output extension=".htm" #>
    
    <# 'Uncomment this line if you want to debug the generated transformation class. #>
    <# 'System.Diagnostics.Debugger.Break() #>
    
    <# Dim i As Integer
       For i = 0 To 2
    
           WriteLine("This is a test")
       Next
    #>
    
  3. Speichern und schließen Sie die Datei.

So testen Sie den benutzerdefinierten Host

  1. Öffnen Sie das Eingabeaufforderungsfenster.

  2. Geben Sie den Pfad der ausführbaren Datei für den benutzerdefinierten Host ein, drücken Sie aber noch nicht die EINGABETASTE.

    Beispiel:

    <YOUR PATH>CustomHost\bin\Debug\CustomHost.exe

    Tipp

    Anstatt die Adresse einzugeben, können Sie auch in Windows-Explorer zur Datei "CustomHost.exe" navigieren und die Datei dann in das Eingabeaufforderungsfenster ziehen.

  3. Geben Sie ein Leerzeichen ein.

  4. Geben Sie den Pfad der Textvorlagendatei ein, und drücken Sie dann die EINGABETASTE.

    Beispiel:

    C:\<YOUR PATH>TestTemplate.tt

    Tipp

    Anstatt die Adresse einzugeben, können Sie auch in Windows-Explorer zur Datei "TestTemplate.tt" navigieren und die Datei dann in das Eingabeaufforderungsfenster ziehen.

    Die benutzerdefinierte Hostanwendung wird ausgeführt und schließt den Textvorlagen-Transformationsprozess ab.

  5. Navigieren Sie in Windows-Explorer zu dem Ordner, der die Datei "TestTemplate.tt" enthält.

    Dieser Ordner enthält auch die Datei "TestTemplate1.txt".

  6. Öffnen Sie diese Datei, um die Ergebnisse der Textvorlagentransformation anzuzeigen.

    Die generierte Textausgabe wird angezeigt und sieht wie folgt aus:

    Text Template Host Test
    
    
    
    
    This is a test
    This is a test
    This is a test
    

Nächste Schritte

In dieser exemplarischen Vorgehensweise haben Sie einen Textvorlagen-Transformationshost erstellt, der die grundlegende Transformationsfunktion unterstützt. Sie können den Host erweitern, um Textvorlagen zu unterstützen, die benutzerdefinierte oder generierte Direktivenprozessoren aufrufen. Weitere Informationen finden Sie unter Exemplarische Vorgehensweise: Verbinden eines Hosts mit einem generierten Direktivenprozessor.

Siehe auch

Referenz

ITextTemplatingEngineHost