TaskHost.SetExpression Method

Artigo
12/03/2008

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)

Syntax

'Declaration
Public Sub SetExpression ( _
    propertyName As String, _
    expression As String _
)

public void SetExpression (
    string propertyName,
    string expression
)

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

public final void SetExpression (
    String propertyName, 
    String expression
)

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

Parameters

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

expression
The expression.

Remarks

The propertyName can be any property available on the object.

Example

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

Thread Safety

Any public static (Shared in Microsoft Visual Basic) members of this type are thread safe. Any instance members are not guaranteed to be thread safe.

Platforms

Development Platforms

For a list of the supported platforms, see Hardware and Software Requirements for Installing SQL Server 2005.

Target Platforms