TaskHost.SetExpression Method (String, String)


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

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

public void SetExpression(
	string propertyName,
	string expression


Type: System.String

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

Type: System.String

The expression.

The propertyName can be any property available on the object.

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

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