IDTSPropertiesProvider.SetExpression(String, String) 方法

定义

将指定的表达式分配给属性。 指定 null 以从属性中删除现有表达式。

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

参数

propertyName
String

向其分配表达式的属性的名称。

expression
String

表达式。

示例

ConnectionManager 继承自 IDTSPropertiesProvider 接口。 下面的代码示例演示如何 ConnectionManager 使用 SetExpression 继承的类及其 GetExpression 方法。

using System;  
using System.Collections.Generic;  
using System.Text;  
using Microsoft.SqlServer.Dts.Runtime;  

namespace ConnMgr_Properties_Collection  
{  
    class Program  
    {  
        static void Main(string[] args)  
        {  
            // The package is one of the SSIS Samples.  
            string mySample = @"C:\Program Files\Microsoft SQL Server\100\Samples\Integration Services\Package Samples\CalculatedColumns Sample\CalculatedColumns\CalculatedColumns.dtsx";  

            // Create an application and load the sample.  
            Application app = new Application();  
            Package pkg = app.LoadPackage(mySample, null);  
            Connections myConns = pkg.Connections;  

            // Get the Properties collection from the connection manager.  
            ConnectionManager myConnMgr = myConns[0];  
            DtsProperties connProperties = myConnMgr.Properties;  

            // View information about the RetainSameConnection property   
            // before setting it using the SetExpression method.  
            Boolean hasProperty = connProperties.Contains("RetainSameConnection");  
            Console.WriteLine("has RetainSameConnection? {0}", hasProperty);  
            Object myValue = myConnMgr.Properties["RetainSameConnection"].GetValue(myConnMgr);  
            String mySValue = myValue.ToString();  
            Console.WriteLine("value before is {0}", mySValue);String myTrueString = "true";  

            // Use SetExpression to set the value to true.  
myConnMgr.Properties["RetainSameConnection"].SetExpression(myConnMgr, myTrueString);  

            // Validate the package to set the expression on the property.  
            DTSExecResult valResult = pkg.Validate(myConns, null, null, null);  

            // Now that the value has been set, retrieve the value  
            // and the expression.  
            myValue = myConnMgr.Properties["RetainSameConnection"].GetValue(myConnMgr);  
            mySValue = myValue.ToString();  
            String myExpression = myConnMgr.Properties["RetainSameConnection"].GetExpression(myConnMgr);  
            String mySExpression = myExpression.ToString();  
            Console.WriteLine("value and expression is {0}, {1}", mySValue, mySExpression);   
        }  
    }  
}  
Imports System  
Imports System.Collections.Generic  
Imports System.Text  
Imports Microsoft.SqlServer.Dts.Runtime  

Namespace ConnMgr_Properties_Collection  
    Class Program  
        Shared  Sub Main(ByVal args() As String)  
        ' The package is one of the SSIS Samples.  
        Dim mySample As String = "C:\Program Files\Microsoft SQL Server\100\Samples\Integration Services\Package Samples\CalculatedColumns Sample\CalculatedColumns\CalculatedColumns.dtsx"  

        ' Create an application and load the sample.  
        Dim app As New Application()  
        Dim pkg As Package = app.LoadPackage(mySample, Nothing)  
        Dim myConns As Connections = pkg.Connections  

        ' Get the Properties collection from the connection manager.  
        Dim myConnMgr As ConnectionManager = myConns(0)  
        Dim connProperties As DtsProperties = myConnMgr.Properties  

        ' View information about the RetainSameConnection property   
        ' before setting it using the SetExpression method.  
        Dim hasProperty As [Boolean] = connProperties.Contains("RetainSameConnection")  
        Console.WriteLine("has RetainSameConnection? {0}", hasProperty)  
        Dim myValue As [Object] = myConnMgr.Properties("RetainSameConnection").GetValue(myConnMgr)  
        Dim mySValue As String = myValue.ToString()  
        Console.WriteLine("value before is {0}", mySValue)  
        Dim myTrueString As String = "true"  

        ' Use SetExpression to set the value to true.  
myConnMgr.Properties("RetainSameConnection").SetExpression(myConnMgr, myTrueString)  

        ' Validate the package to set the expression on the property.  
        Dim valResult As DTSExecResult = pkg.Validate(myConns, Nothing, Nothing, Nothing)  

        ' Now that the value has been set, retrieve the value  
        ' and the expression.  
        myValue = myConnMgr.Properties("RetainSameConnection").GetValue(myConnMgr)  
        mySValue = myValue.ToString()  
        Dim myExpression As String = myConnMgr.Properties("RetainSameConnection").GetExpression(myConnMgr)  
        Dim mySExpression As String = myExpression.ToString()  
        Console.WriteLine("value and expression is {0}, {1}", mySValue, mySExpression)   
        End Sub  
    End Class  
End Namespace  

示例输出:

RetainSameConnection 吗? True

值为 False 之前的值

值和表达式为 True、true

注解

可以是 propertyName 对象上可用的任何属性。

适用于