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TaskHost.SetExpression(String, String) Method

Definition

Assigns the specified expression to the property. Specify null to remove an existing expression from the property.

public:
 virtual void SetExpression(System::String ^ propertyName, System::String ^ expression);
public void SetExpression (string propertyName, string expression);
abstract member SetExpression : string * string -> unit
override this.SetExpression : string * string -> unit
Public Sub SetExpression (propertyName As String, expression As String)

Parameters

propertyName
String

The name of the property to which to assign the expression.

expression
String

The expression.

Implements

Examples

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

Remarks

The propertyName can be any property available on the object.

Applies to