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Variable.EvaluateAsExpression Property

Definition

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

public:
 property bool EvaluateAsExpression { bool get(); void set(bool value); };
[Microsoft.SqlServer.Dts.Runtime.Localization.LocalizablePropertyDescription(typeof(Microsoft.SqlServer.Dts.Runtime.Localized), "EvaluateAsExpressionDesc")]
public bool EvaluateAsExpression { get; set; }
[<Microsoft.SqlServer.Dts.Runtime.Localization.LocalizablePropertyDescription(typeof(Microsoft.SqlServer.Dts.Runtime.Localized), "EvaluateAsExpressionDesc")>]
member this.EvaluateAsExpression : bool with get, set
Public Property EvaluateAsExpression As Boolean

Property Value

true if the variable contains an expression; otherwise, false.

Attributes

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

Remarks

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

Applies to