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《深入浅出WPF》读书笔记.4名称空间详解

背景

主要讲明名称空间概念，可以理解为命名空间的引用。

xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"

👆如x可以理解为一些列命名空间的引用。

不一一列举，只讲几个特殊的名称空间x:Type x:Null x:Data x:Code

代码

x:Type

指定数据类型

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
using System.Windows;
using System.Windows.Controls;namespace WpfBookDemo
{public class MyButton:Button{public Type UserWindowType {  get; set; }protected override void OnClick(){base.OnClick();Window win=Activator.CreateInstance(this.UserWindowType) as Window;if(win is not null){win.Show();}}}
}

<Window x:Class="WpfBookDemo.MyWindow"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"xmlns:local="clr-namespace:WpfBookDemo"mc:Ignorable="d"Title="MyWindow" Height="300" Width="300" ><Grid><StackPanel VerticalAlignment="Center"><TextBox Width="120" Background="LightGreen" Margin="5"></TextBox><TextBox Width="120" Background="LightGreen" Margin="5"></TextBox><TextBox Width="120" Background="LightGreen" Margin="5"></TextBox><Button Width="120" Background="LightGreen" Content="点击一下" Margin="5"></Button></StackPanel></Grid>
</Window>

<Window x:Class="WpfBookDemo.xTypeDemo"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"xmlns:local="clr-namespace:WpfBookDemo"mc:Ignorable="d"Title="xTypeDemo" Height="450" Width="800"><Grid><local:MyButton x:Name="mbtn" Content="点击一下" Width="120" Height="40"UserWindowType="{x:Type local:MyWindow}"></local:MyButton></Grid>
</Window>

x:Null

为属性设置空值

<Window x:Class="WpfBookDemo.xNullDemo"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"xmlns:local="clr-namespace:WpfBookDemo"mc:Ignorable="d"Title="xNullDemo" Height="450" Width="300"><Window.Resources><Style x:Key="{x:Type Button}" TargetType="{x:Type Button}"><Setter Property="Width" Value="60"></Setter><Setter Property="Height" Value="36"></Setter><Setter Property="Margin" Value="5"></Setter></Style></Window.Resources><Grid><StackPanel VerticalAlignment="Center"><Button></Button><Button ></Button><Button ></Button><Button  Style="{x:Null}" Content="没有样式"></Button></StackPanel></Grid>
</Window>

x:Data

数据提供者

<Window x:Class="WpfBookDemo.xDataDemo"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"xmlns:local="clr-namespace:WpfBookDemo"mc:Ignorable="d"Title="xDataDemo" Height="200" Width="300"><Window.Resources><XmlDataProvider x:Key="InventoryData" XPath="Fruits"><x:XData xmlns=""><Fruits ><Fruit Name="Apple">Apple</Fruit><Fruit Name="Banana">Banana</Fruit><Fruit Name="Orange">Orange</Fruit></Fruits></x:XData></XmlDataProvider></Window.Resources><Grid><StackPanel VerticalAlignment="Center" Height="150"><ListBox ItemsSource="{Binding Source={StaticResource InventoryData}, XPath=Fruit}"></ListBox></StackPanel></Grid>
</Window>

x:Code

可以将后端代码挪到xam中

<Window x:Class="WpfBookDemo.xCodeDemo"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"xmlns:local="clr-namespace:WpfBookDemo"mc:Ignorable="d"Title="xCodeDemo" Height="450" Width="800"><Grid><StackPanel VerticalAlignment="Center" HorizontalAlignment="Center"><Button x:Name="btn" Content="点击一下" Click="btn_Click" Width="120" Height="40"></Button></StackPanel></Grid><x:Code><![CDATA[private void btn_Click(object sender, RoutedEventArgs e){MessageBox.Show("使用x:Code可以将后端代码挪动到前端！");}]]></x:Code>
</Window>

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不想写代码，只想干黑悟空，但是菜！