wpf - x:ClassModifier directive to change the default visibility of the class-优快云博客

本文介绍了如何使用XAML关键字x:ClassModifier来指定由XAML生成的类的可见性级别，例如将其设置为internal而非默认的public。此技巧对于解决特定编译错误尤其有用，例如当XAML定义的类需要实现内部接口时。

By default, if you write xaml code, the visibility of the class that you wrote is public. While sometime you want to make the class that generated by XAML to be non-public, situation like the class that you wrote extends from an internal interface and you the code will stop to compile if you don't have the x:ClassModifier directive.

On book "WPF 4 Unleased", x:ClassModifer among other directives are names so called XAML keywords.

x:ClassModifier directive is only applicable on the root element where the x:Class attribute is applying..

the official document on the x:ClassModifier is available on this page : x:ClassModifier Directive;

let me show you some code on how to use it.

<UserControl
    xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
    xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml" xmlns:d="http://schemas.microsoft.com/expression/blend/2008" xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006" mc:Ignorable="d" BorderThickness="0"
    x:Class="Previews.PrintPreviewView"
    VerticalAlignment="Stretch" HorizontalAlignment="Stretch"
    MinWidth="700" MinHeight="500" Background="#FFEBEBEB" 
    x:ClassModifier="internal"
    >
</UserControl>

the visibility of the class should be consistent, so you will have the following code in the code-behind definition.

internal partial class PrintPreviewView : IPrintControlView
{
...
}