Variable.EvaluateAsExpression Property

Artigo
12/03/2008

Gets or sets a Boolean that indicates that 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

public bool EvaluateAsExpression { get; set; }

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

/** @property */
public boolean get_EvaluateAsExpression ()

/** @property */
public void set_EvaluateAsExpression (boolean value)

public function get EvaluateAsExpression () : boolean

public function set EvaluateAsExpression (value : boolean)

Property Value

A Boolean that indicates if the variable contains an expression.

Remarks

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

Example

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

Thread Safety

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.

Platforms

Development Platforms

For a list of the supported platforms, see Hardware and Software Requirements for Installing SQL Server 2005.

Target Platforms