BaseValidatorDesigner.GetDesignTimeHtml Method ()
Gets the markup that is used to render the associated control at design time.
Assembly: System.Design (in System.Design.dll)
Return Value
Type: System.StringA string containing the markup used to render the BaseValidator at design time.
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.
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 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
Available since 1.1