Variable.EvaluateAsExpression 屬性

Gets or sets a Boolean that indicates whether the variable contains an expression.

命名空間：  Microsoft.SqlServer.Dts.Runtime
組件：  Microsoft.SqlServer.ManagedDTS (在 Microsoft.SqlServer.ManagedDTS.dll 中)

語法

'宣告
Public Property EvaluateAsExpression As Boolean 
    Get 
    Set
'用途
Dim instance As Variable 
Dim value As Boolean 

value = instance.EvaluateAsExpression

instance.EvaluateAsExpression = value

public bool EvaluateAsExpression { get; set; }

public:
property bool EvaluateAsExpression {
    bool get ();
    void set (bool value);
}

member EvaluateAsExpression : bool with get, set

function get EvaluateAsExpression () : boolean 
function set EvaluateAsExpression (value : boolean)

屬性值

型別：System.Boolean
true if the variable contains an expression; otherwise, false.

備註

Expressions and variables can be used to control the flow of a package. For more information, see 將運算式加入優先順序條件約束.

範例

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

請參閱

參考

Variable 類別

Microsoft.SqlServer.Dts.Runtime 命名空間