BaseValidatorDesigner.GetDesignTimeHtml Method

Definition

Namespace:

System.Web.UI.Design.WebControls

Assembly:

System.Design.dll

Gets the markup that is used to render the associated control at design time.

public:
 override System::String ^ GetDesignTimeHtml();

public override string GetDesignTimeHtml ();

override this.GetDesignTimeHtml : unit -> string

Public Overrides Function GetDesignTimeHtml () As String

Returns

String

A string containing the markup used to render the BaseValidator at design time.

Examples

The following code example shows how to override the GetDesignTimeHtml method that draws a solid border around the associated control at design time if the value of the BorderStyle property of the control is set to the NotSet or None field.

// Make the full extent of the control more visible in the designer.
// If the border style is None or NotSet, change the border to a 
// solid line. 
public override string GetDesignTimeHtml()
{
    // Get a reference to the control or a copy of the control.
    SimpleCompareValidator myCV = (SimpleCompareValidator)ViewControl;
    string markup = null;

    // Check if the border style should be changed.
    if (myCV.BorderStyle == BorderStyle.NotSet ||
        myCV.BorderStyle == BorderStyle.None)
    {
        // Save the current property setting.
        BorderStyle oldBorderStyle = myCV.BorderStyle;

        // Set the design-time property and catch any exceptions.
        try
        {
            myCV.BorderStyle = BorderStyle.Solid;

            // Call the base method to generate the markup.
            markup = base.GetDesignTimeHtml();
        }
        catch (Exception ex)
        {
            markup = GetErrorDesignTimeHtml(ex);
        }
        finally
        {
            // Restore the property to its original setting.
            myCV.BorderStyle = oldBorderStyle;
        }
    }
    else
    {
        // Call the base method to generate the markup.
        markup = base.GetDesignTimeHtml();
    }

    return markup;
} // GetDesignTimeHtml

' Make the full extent of the control more visible in the designer.
' If the border style is None or NotSet, change the border to a 
' solid line. 
Public Overrides Function GetDesignTimeHtml() As String

    ' Get a reference to the control or a copy of the control.
    Dim myCV As SimpleCompareValidator = _
        CType(ViewControl, SimpleCompareValidator)
    Dim markup As String

    ' Check if the border style should be changed.
    If (myCV.BorderStyle = BorderStyle.NotSet Or _
        myCV.BorderStyle = BorderStyle.None) Then

        ' Save the current property setting.
        Dim oldBorderStyle As BorderStyle = myCV.BorderStyle

        ' Set the design-time property and catch any exceptions.
        Try
            myCV.BorderStyle = BorderStyle.Solid

            ' Call the base method to generate the markup.
            markup = MyBase.GetDesignTimeHtml()

        Catch ex As Exception
            markup = GetErrorDesignTimeHtml(ex)

        Finally
            ' Restore the property to its original setting.
            myCV.BorderStyle = oldBorderStyle
        End Try

    Else
        ' Call the base method to generate the markup.
        markup = MyBase.GetDesignTimeHtml()
    End If

    Return markup
End Function

Remarks

If the ErrorMessage or Text property of the associated control that is derived from the BaseValidator class is an empty string (""), or if the Display property is set to the None field, the GetDesignTimeHtml method sets the ErrorMessage property to the control ID, which is enclosed in brackets ([]) and sets the Display property to the Static field. The GetDesignTimeHtml then calls the GetDesignTimeHtml base method to generate the markup, and restores the control properties to their original values, if necessary.

See also

• BaseValidator
• ErrorMessage
• Display
• ValidatorDisplay
• GetDesignTimeHtml()