Variable.Expression Property 
Definition
Important
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Gets or sets the expression contained in a variable.
public:
 property System::String ^ Expression { System::String ^ get(); void set(System::String ^ value); };[Microsoft.SqlServer.Dts.Runtime.Localization.LocalizablePropertyDescription(typeof(Microsoft.SqlServer.Dts.Runtime.Localized), "ExpressionDesc")]
public string Expression { get; set; }[<Microsoft.SqlServer.Dts.Runtime.Localization.LocalizablePropertyDescription(typeof(Microsoft.SqlServer.Dts.Runtime.Localized), "ExpressionDesc")>]
member this.Expression : string with get, setPublic Property Expression As StringProperty Value
A String that contains the expression.
- 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
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.