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TaskHost.SetExpression Method

Assigns the specified expression to the property. Specify nulla null reference (Nothing in Visual Basic) to remove an existing expression from the property.

Namespace:  Microsoft.SqlServer.Dts.Runtime
Assembly:  Microsoft.SqlServer.ManagedDTS (in Microsoft.SqlServer.ManagedDTS.dll)

Syntax

'Declaration
Public Sub SetExpression ( _
    propertyName As String, _
    expression As String _
)
'Usage
Dim instance As TaskHost
Dim propertyName As String
Dim expression As String

instance.SetExpression(propertyName, _
    expression)

public void SetExpression(
    string propertyName,
    string expression
)

public:
virtual void SetExpression(
    String^ propertyName, 
    String^ expression
) sealed

abstract SetExpression : 
        propertyName:string * 
        expression:string -> unit 
override SetExpression : 
        propertyName:string * 
        expression:string -> unit 

public final function SetExpression(
    propertyName : String, 
    expression : String
)

Parameters

  • propertyName
    Type: System.String
    The name of the property to which to assign the expression.

Implements

IDTSPropertiesProvider.SetExpression(String, String)

Remarks

The propertyName can be any property available on the object.

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