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LoginViewDesigner.GetEmptyDesignTimeHtml Method

  • Reference

Definition

Namespace:
System.Web.UI.Design.WebControls
Assembly:
System.Design.dll

Gets the markup that renders a placeholder for the associated control at design time when the current template is not defined.

protected:
 override System::String ^ GetEmptyDesignTimeHtml();
protected override string GetEmptyDesignTimeHtml ();
override this.GetEmptyDesignTimeHtml : unit -> string
Protected Overrides Function GetEmptyDesignTimeHtml () As String

Returns

String

A string containing markup text that renders to a placeholder on the design surface.

Examples

The following code example shows how to override the GetEmptyDesignTimeHtml method in a class that is inherited from the LoginViewDesigner class to change the appearance of a control that is derived from the LoginView class at design time. The example generates the markup for a placeholder that includes the names of all the RoleGroup objects that are defined for the associated control.

// Generate the design-time markup for the control 
// when the template is empty.
protected override string GetEmptyDesignTimeHtml()
{
    // Generate a design-time placeholder containing the names of all
    // the role groups.
    MyLoginView myLoginViewCtl = (MyLoginView)ViewControl;
    RoleGroupCollection roleGroups = myLoginViewCtl.RoleGroups;
    string roleNames = null;

    // If there are any role groups, form a string of their names.
    if (roleGroups.Count > 0)
    {
        roleNames = "Role Groups: <br />   " + 
            roleGroups[0].ToString();

        for( int rgX = 1; rgX < roleGroups.Count; rgX++ )
            roleNames += 
                "<br />   " + roleGroups[rgX].ToString();
    }
    return CreatePlaceHolderDesignTimeHtml( roleNames);
} // GetEmptyDesignTimeHtml

' Generate the design-time markup for the control 
' when the template is empty.
Protected Overrides Function GetEmptyDesignTimeHtml() As String

    ' Generate a design-time placeholder containing the names of all
    ' the role groups.
    Dim myLoginViewCtl As MyLoginView = CType(ViewControl, MyLoginView)
    Dim roleGroups As RoleGroupCollection = myLoginViewCtl.RoleGroups
    Dim RoleNames As String = Nothing
    Dim rgX As Integer

    ' If there are any role groups, form a string of their names.
    If roleGroups.Count > 0 Then

        roleNames = "Role Groups: <br />   " & _
            roleGroups(0).ToString()

        For rgX = 1 To roleGroups.Count - 1
            roleNames &= "<br />   " & _
                roleGroups(rgX).ToString()
        Next rgX
    End If

    Return CreatePlaceHolderDesignTimeHtml(roleNames)

End Function ' GetEmptyDesignTimeHtml

Remarks

The GetEmptyDesignTimeHtml method first formats a string message that specifies the name of the current template of the associated LoginView control and also specifies that the template is empty. Then the GetEmptyDesignTimeHtml generates the markup for a placeholder containing that message.

Applies to

See also