TaskHost.GetExpression 方法

Returns the expression for the specified property. Null means no expression is assigned.

命名空間：  Microsoft.SqlServer.Dts.Runtime
組件：  Microsoft.SqlServer.ManagedDTS (在 Microsoft.SqlServer.ManagedDTS.dll 中)

語法

'宣告
Public Function GetExpression ( _
    propertyName As String _
) As String
'用途
Dim instance As TaskHost 
Dim propertyName As String 
Dim returnValue As String 

returnValue = instance.GetExpression(propertyName)

public string GetExpression(
    string propertyName
)

public:
virtual String^ GetExpression(
    String^ propertyName
) sealed

abstract GetExpression : 
        propertyName:string -> string  
override GetExpression : 
        propertyName:string -> string

public final function GetExpression(
    propertyName : String
) : String

參數

• propertyName
  型別：System.String
  The name of the property whose expression you want to see.

傳回值

型別：System.String
A String that contains the expression used to evaluate the property.

實作

IDTSPropertiesProvider.GetExpression(String)

備註

The propertyName can be any property available on the object.

範例

The following code example shows how to use the SetExpression and GetExpression methods of the TaskHost. For this code example, the hosted task is the BulkInsertTask.

using System;
using System.Collections.Generic;
using System.Text;
using Microsoft.SqlServer.Dts.Runtime;
using Microsoft.SqlServer.Dts.Tasks.BulkInsertTask;


namespace Microsoft.SqlServer.SSIS.Sample
{
    class Program
        {
        static void Main(string[] args)
        {
            Package pkg = new Package();
            TaskHost th = (TaskHost)pkg.Executables.Add("STOCK:BulkInsertTask");

            // View information about the CheckConstraints property
            // before setting it using the SetExpression method.
            Boolean checkConstraint = (Boolean)th.Properties["CheckConstraints"].GetValue(th);
            Console.WriteLine("Original value of CheckConstraints: {0}", checkConstraint);

            // Use SetExpression to set the value to true.
            String myTrueString = "true";
            th.Properties["CheckConstraints"].SetExpression(th, myTrueString);

            // Validate the package to set the expression onto the property.
            DTSExecResult valResult = pkg.Validate(null, null, null, null);

            // Retrieve the new value and the expression.
            checkConstraint = (Boolean)th.Properties["CheckConstraints"].GetValue(th);
            String myExpression = th.Properties["CheckConstraints"].GetExpression(th);
            Console.WriteLine("New value of CheckConstraints: {0}", checkConstraint);
            Console.WriteLine("Expression for CheckConstraints: {0}", myExpression);
        }
    }
}

Sample Output:

Original value of CheckConstraints: False

New value of CheckConstraints: True

Expression for CheckConstraints: true

請參閱

參考

TaskHost 類別

Microsoft.SqlServer.Dts.Runtime 命名空間