Create a Connection String

Overview

The Data Access Tool can help you create one of two basic types of connection strings: an OLE DB connection string stored in a universal data link (.udl) file, and an ADO.NET connection string stored in a text connection string file (*.txt).

Create a connection string for a .udl File

A universal data link (.udl) file is essentially a text file that contains the connection string for an OLE DB data source. You can create a .udl file by using the appropriate DB2OleDbConnectionString or FileSysOleDbConnectionString constructor, and then save the string to secondary storage with a call to Save. The Data Access Library automatically creates the appropriate .udl file to store the string in, and save the file to disk.

1. Create an empty connection string by calling a connection string constructor.

   Calling the constructor creates a connection string with default settings. These default settings can be set only through the Data Access Tool user interface.

   If you use a file path for a file that currently exists, the system loads the connection string information in that file instead.

   You can determine the default path your system uses for storing .udl files with a call to DataAccessSettings.MakeUDLPath. DataAccessSettings also stores the default paths for DSN and HCD files.

2. Add in the relevant connection information to the connection string by calling the various connection string properties, such as DataSourceName, UserName, or Password.

   You can also retrieve the full connection string as a text string with a call to GetString, and then save the modified string with SetString.

3. Save the string by calling the relevant Save method, such as DB2OleDbConnectionString.Save.

   The system saves the connection string in a .udl file. The system creates the .udl file using the file path passed in the name parameter of the constructor. If the file does not contain the full path, the system uses the default path as described in DataAccessSettings.UDLpath.

   The following code example demonstrates how to create a .udl file using a new file name, user name, and password.

   Caution

   This example or guidance references sensitive information, such as a connection string or a username and password. Never hardcode these values in your code, and make sure that you protect confidential data by using the most secure authentication available. For more information, see the following documentation:

   • Security in BizTalk Server
   • Security for sending and receiving messages
   • Access control and data security

   static DB2OleDbConnectionString CreateUDLFile(string FileName, string NameOfUser, string PassWord, ref System.Exception myException)  
   {  
      try  
      {  
         DB2OleDbConnectionString myConnection = new DB2OleDbConnectionString(FileName, false);  
         myConnection.UserName = NameOfUser;  
         myConnection.Password = PassWord;  
         myConnection.Save();  
         System.Exception MyEx= new System.Exception(@"Successful Creation", null);  
         myException = MyEx;  
         return myConnection;  
      }  
      catch (Exception ex)  
      {  
         myException = ex;  
         return null;  
      }  
   }  
   

See Also

Data Access Library Tasks