输入按键事件处理程序

4 回答

• 86

  KeyDown或KeyUp .

  TextBox tb = new TextBox();
  tb.KeyDown += new KeyEventHandler(tb_KeyDown);
  
  static void tb_KeyDown(object sender, KeyEventArgs e)
  {
      if (e.KeyCode == Keys.Enter)
      {
          //enter key is down
      }
  }
  

  回复于 2024-05-03T13:48:20+08:00
• 3

  您还可以在WPF中使用PreviewKeyDown：

  <TextBox PreviewKeyDown="EnterClicked" />
  

  或者在C＃中：

  myTextBox.PreviewKeyDown += EnterClicked;
  

  然后在附加课程中：

  void EnterClicked(object sender, KeyEventArgs e) {
      if(e.Key == Key.Return) {
          DoSomething();
          e.Handled = true;
      }
  }
  

  回复于 2024-05-03T13:48:20+08:00
• 7

  KeyDown事件仅通过“普通”输入键在标准TextBox或MaskedTextBox中触发，而不是ENTER或TAB等 .

  通过重写IsInputKey方法，可以获得像ENTER这样的特殊键：

  public class CustomTextBox : System.Windows.Forms.TextBox
  {
      protected override bool IsInputKey(Keys keyData)
      {
          if (keyData == Keys.Return)
              return true;
          return base.IsInputKey(keyData);
      }
  }
  

  然后可以通过以下方式使用KeyDown事件：

  CustomTextBox ctb = new CustomTextBox();
  ctb.KeyDown += new KeyEventHandler(tb_KeyDown);
  
  private void tb_KeyDown(object sender, KeyEventArgs e)
  {
      if (e.KeyCode == Keys.Enter)
      {
            //Enter key is down
  
            //Capture the text
            if (sender is TextBox)
            {
                TextBox txb = (TextBox)sender;
                MessageBox.Show(txb.Text);
            }
      }
  }
  

  回复于 2024-05-03T13:48:20+08:00
• 19

  在WPF中，TextBox元素将无法使用“Enter”按钮创建KeyUp事件，直到您不设置属性：AcceptsReturn =“True” .

  但是，它将解决在TextBox元素中处理KeyUp事件的问题 . 按“ENTER”后，您将在TextBox中获得一个新的文本行 .

  我通过使用Bubble事件策略解决了使用TextBox元素的KeyUp Event的问题 . 这很简单 . 您必须在某个（任何）父元素中附加KeyUp事件处理程序：

  XAML：

  <Window x:Class="TextBox_EnterButtomEvent.MainWindow"
      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:TextBox_EnterButtomEvent"
      mc:Ignorable="d"
      Title="MainWindow" Height="350" Width="525">
  <Grid KeyUp="Grid_KeyUp">
      <Grid.RowDefinitions>
          <RowDefinition/>
          <RowDefinition Height="Auto"/>
          <RowDefinition Height="Auto"/>
          <RowDefinition Height ="0.3*"/>
          <RowDefinition Height="Auto"/>
          <RowDefinition Height="Auto"/>
          <RowDefinition/>
      </Grid.RowDefinitions>
      <Grid.ColumnDefinitions>
          <ColumnDefinition/>
          <ColumnDefinition/>
          <ColumnDefinition/>
      </Grid.ColumnDefinitions>
      <TextBlock Grid.Row="1" Grid.Column="1" Padding="0" TextWrapping="WrapWithOverflow">
          Input text end press ENTER:
      </TextBlock>
      <TextBox Grid.Row="2" Grid.Column="1" HorizontalAlignment="Stretch"/>
      <TextBlock Grid.Row="4" Grid.Column="1" Padding="0" TextWrapping="WrapWithOverflow">
          You have entered:
      </TextBlock>
      <TextBlock Name="txtBlock" Grid.Row="5" Grid.Column="1" HorizontalAlignment="Stretch"/>
  </Grid></Window>
  

  C＃逻辑部分（KeyUp事件处理程序附加到网格元素）：

  public partial class MainWindow : Window
  {
      public MainWindow()
      {
          InitializeComponent();
      }
  
      private void Grid_KeyUp(object sender, KeyEventArgs e)
      {
          if(e.Key == Key.Enter)
          {
              TextBox txtBox = e.Source as TextBox;
              if(txtBox != null)
              {
                  this.txtBlock.Text = txtBox.Text;
                  this.txtBlock.Background = new SolidColorBrush(Colors.LightGray);
              }
          }
      }
  }
  

  结果：

  Image with result

  回复于 2024-05-03T13:48:20+08:00