Variable.EvaluateAsExpression Property

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

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

Syntax

'Declaration
Public Property EvaluateAsExpression As Boolean 
    Get 
    Set
'Usage
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)

Property Value

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

Remarks

Expressions and variables can be used to control the flow of a package. For more information, see Add Expressions to Precedence Constraints.

Examples

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

See Also

Reference

Variable Class

Microsoft.SqlServer.Dts.Runtime Namespace