Variable.Expression Property

Gets or sets the expression contained in a variable.

命名空间: Microsoft.SqlServer.Dts.Runtime
程序集: Microsoft.SqlServer.ManagedDTS (in microsoft.sqlserver.manageddts.dll)

语法

声明
Public Property Expression As String

public string Expression { get; set; }

public:
property String^ Expression {
    String^ get ();
    void set (String^ value);
}

/** @property */
public String get_Expression ()

/** @property */
public void set_Expression (String value)

public function get Expression () : String

public function set Expression (value : String)

属性值

A String that contains the expression.

备注

The Expression method returns the expression entered in the value property only when the EvaluateAsExpression property is set to true; otherwise, an empty string is returned if false.

示例

The following example sets the EvaluateAsExpression flag to show that the variable contains an expression, and then can use the Expression property.

static void Main(string[] args)
    {
        Package p = new Package();
        p.Variables.Add("x", false, "", 1);
        Variable v = p.Variables.Add("y", false, "", 1);
        v.Expression = "@x + 10";
        v.EvaluateAsExpression = true;
        if (v.Value.ToString() == "11")
            Console.WriteLine("Value was 11");
        else
            Console.WriteLine("Value was not 11");
    }

Shared  Sub Main(ByVal args() As String)
        Dim p As Package =  New Package() 
        p.Variables.Add("x", False, "", 1)
        Dim v As Variable =  p.Variables.Add("y",False,"",1) 
        v.Expression = "@x + 10"
        v.EvaluateAsExpression = True
        If v.Value.ToString() = "11" Then
            Console.WriteLine("Value was 11")
        Else 
            Console.WriteLine("Value was not 11")
        End If
End Sub

Sample Output:

Value was 11

线程安全

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.

平台

开发平台

有关支持的平台列表，请参阅安装 SQL Server 2005 的硬件和软件要求。

目标平台

有关支持的平台列表，请参阅安装 SQL Server 2005 的硬件和软件要求。

请参阅

参考

Variable Class
Variable Members
Microsoft.SqlServer.Dts.Runtime Namespace