TextBox 事件

1.键盘事件

　　

　　界面代码：

    <Grid>
        <Grid.RowDefinitions>
            <RowDefinition Height="auto"></RowDefinition>
            <RowDefinition Height="*"></RowDefinition>
            <RowDefinition Height="auto"></RowDefinition>
        </Grid.RowDefinitions>
        <DockPanel Grid.Row="0">
            <TextBlock>Type here:</TextBlock>
            <TextBox Focusable="True" Width="710" PreviewKeyDown="PKeyUpAndDown" PreviewKeyUp="PKeyUpAndDown" KeyDown="PKeyUpAndDown" KeyUp="PKeyUpAndDown" PreviewTextInput="PTextInput" TextInput="PTextInput"></TextBox>
        </DockPanel>
        <ListBox Grid.Row="1" Margin="10,10,10,44" Name="mylistbox"></ListBox>
        <Button Click="Button_Click_2" Grid.Row="2" HorizontalAlignment="Right" Width="60" Margin="0,0,20,30">clear</Button>
    </Grid>

　　事件代码：

private void Button_Click_2(object sender, RoutedEventArgs e)
        {
            this.mylistbox.Items.Clear();
        }

        private void PKeyUpAndDown(object sender, KeyEventArgs e)
        {
            string message = "Event:" + e.RoutedEvent + "  " + "key:" + e.Key;
            this.mylistbox.Items.Add(message);
        }

        private void PTextInput(object sender, TextCompositionEventArgs e)
        {
            string message = "Event:" + e.RoutedEvent + "  " + "key:" + e.Text;
            this.mylistbox.Items.Add(message);
        }

 

　　效果图：

 2.选中事件

　　

　　前端代码

    <Grid>
        <Grid.RowDefinitions>
            <RowDefinition></RowDefinition>
            <RowDefinition></RowDefinition>
        </Grid.RowDefinitions>
        <TextBox Grid.Row="0" Name="textbox1" TextWrapping="Wrap" SelectionChanged="TextBox_SelectionChanged">
            hello world
            hello world
            hello world
            hello world
        </TextBox>
        <TextBlock  Grid.Row="1" Name="tb"></TextBlock>
    </Grid>

　　后台代码

        private void TextBox_SelectionChanged(object sender, RoutedEventArgs e)
        {
            if (this.textbox1.SelectionLength == 0) return;
            this.tb.Text = $"选择 {this.textbox1.SelectionStart} to {this.textbox1.SelectionLength} :{this.textbox1.SelectedText}";
        }

　　事件效果：