在Checkbox上执行命令。检查或取消选中

Question

我在窗口上有一个复选框控件。我想要执行一个将调用相关视图模型中的方法的命令。我还需要复选框的值。我似乎无法找到将命令与复选框相关联的方法。有没有人做过这个？

Answer 1

<CheckBox Content="CheckBox" 
      Command="{Binding YourCommand}" 
      CommandParameter="{Binding IsChecked, RelativeSource={RelativeSource Self}}" /> 

Answer 2

这工作，你需要什么 -

<CheckBox CommandParameter="{Binding}" 
      Command="{Binding DataContext.AddRemovePresetAssignmentCommand, 
      RelativeSource={RelativeSource FindAncestor, 
          AncestorType={x:Type UserControl}}}" 
      Content="{Binding Path=Name}"> 

Answer 3

如果你使用MVVM，你可以使用事件触发这样的：

<CheckBox IsChecked="{Binding ServiceOrderItemTask.IsCompleted, Mode=TwoWay}" Content="{Binding ServiceOption.Name}"> 

    <i:Interaction.Triggers> 
      <i:EventTrigger EventName="Checked"> 
       <i:InvokeCommandAction Command="{Binding DataContext.IsCompletedCheckedCommand, RelativeSource={RelativeSource FindAncestor, AncestorType={x:Type t:RadGridView}}}" CommandParameter="{Binding}"/> 
      </i:EventTrigger> 

      <i:EventTrigger EventName="Unchecked"> 
       <i:InvokeCommandAction Command="{Binding DataContext.IsCompletedUncheckedCommand, RelativeSource={RelativeSource FindAncestor, AncestorType={x:Type t:RadGridView}}}" CommandParameter="{Binding}"/> 
      </i:EventTrigger> 
    </i:Interaction.Triggers> 

Answer 4

当你只需要CheckBox的状态（选中或未选中），则不需要参数。

CheckBox box = e.OriginalSource as CheckBox; 

if(box.IsChecked.Value) 
    DoThis(); 
else 
    DoAnotherMethod(); 

“E”是ExecutedRoutedEventArgs参数的命令：当您使用此代码，可以检测复选框的状态。您需要box.IsChecked.Value，因为box.IsChecked来自Type bool ?.

Answer 5

我迟到了......我用Rohit Vats回答了这个问题。

该示例是一个工作代码提取，它只是在这里帮助理解每个方面。它是一个图钉，可以是活动的或不活动的，它使用DelegateCommand。您也可以使用RelayCommand或其他类似的类来完成相同的工作。

命令：

using System.Windows.Input; 

namespace HQ.Wpf.Util.Command 
{ 
    public class StandardCommand 
    { 
     public static RoutedUICommand PinPropertyGrid = new RoutedUICommand("Pin property grid", "PinPropertyGrid", typeof(StandardCommand)); 

的XAML：

      <CheckBox HorizontalAlignment="Right" 
             VerticalAlignment="Top" 
             Margin="2,0,3,0" 
             Command="{Binding CommandPinPropertyGrid}" 
             CommandParameter="{Binding IsChecked, RelativeSource={RelativeSource Self}}"> 
           <CheckBox.Template> 
            <ControlTemplate TargetType="{x:Type CheckBox}"> 
             <Grid> 
              <Image x:Name="ImagePushpin" Width="16" Height="16" Source="pack://application:,,,/WpfUtil;component/Images/PushpinUnpinned16x16.png" /> 
             </Grid> 
             <ControlTemplate.Triggers> 
              <Trigger Property="IsChecked" Value="True"> 
               <Setter TargetName="ImagePushpin" Property="Source" Value="pack://application:,,,/WpfUtil;component/Images/PushpinPinned16x16.png" /> 
              </Trigger> 
             </ControlTemplate.Triggers> 
            </ControlTemplate> 
           </CheckBox.Template> 
          </CheckBox> 

型号：

public MainWindowViewModel() 
{ 
    CommandPinPropertyGrid = new DelegateCommand<bool>(PinPropertyGrid); 

...

// ****************************************************************** 
public DelegateCommand<bool> CommandPinPropertyGrid { get; private set; } 

public void PinPropertyGrid(bool pinned) 
{ 
    this.IsPropertyGridPinned = pinned; 
} 

DelegateCommand：

using System; 
using System.Windows.Input; 

namespace HQ.Wpf.Util.Command 
{ 

    /// <summary> 
    /// Represents a command that forwards the <c>Execute</c> and <c>CanExecute</c> calls to specified delegates. 
    /// </summary> 
    public class DelegateCommand<T> : ICommand 
    { 

     private readonly Action<T> _executeCallback; 
     private readonly Predicate<T> _canExecuteCallback; 

     ///////////////////////////////////////////////////////////////////////////////////////////////////// 
     // OBJECT 
     ///////////////////////////////////////////////////////////////////////////////////////////////////// 

     /// <summary> 
     /// Initializes a new instance of the <see cref="DelegateCommand<T>"/> class. 
     /// </summary> 
     /// <param name="executeCallback">The execute callback delegate.</param> 
     public DelegateCommand(Action<T> executeCallback) 
      : this(executeCallback, null) 
     { 
      // No-op 
     } 

     /// <summary> 
     /// Initializes a new instance of the <see cref="DelegateCommand<T>"/> class. 
     /// </summary> 
     /// <param name="executeCallback">The execute callback delegate.</param> 
     /// <param name="canExecuteCallback">The can execute callback delegate.</param> 
     public DelegateCommand(Action<T> executeCallback, Predicate<T> canExecuteCallback) 
     { 
      if (executeCallback == null) 
       throw new ArgumentNullException("executeCallback"); 

      this._executeCallback = executeCallback; 
      this._canExecuteCallback = canExecuteCallback; 
     } 

     ///////////////////////////////////////////////////////////////////////////////////////////////////// 
     // INTERFACE IMPLEMENTATION 
     ///////////////////////////////////////////////////////////////////////////////////////////////////// 

     #region ICommand Members 

     /// <summary> 
     /// Defines the method that determines whether the command can execute in its current state. 
     /// </summary> 
     /// <param name="parameter">Data used by the command. If the command does not require data to be passed, this object can be set to <see langword="null"/>.</param> 
     /// <returns> 
     /// <c>true</c> if this command can be executed; otherwise, <c>false</c>. 
     /// </returns> 
     public bool CanExecute(object parameter) 
     { 
      return (this._canExecuteCallback == null) ? true : this._canExecuteCallback((T)parameter); 
     } 

     /// <summary> 
     /// Occurs when changes occur that affect whether or not the command should execute. 
     /// </summary> 
     public event EventHandler CanExecuteChanged 
     { 
      add 
      { 
       if (this._canExecuteCallback != null) 
        CommandManager.RequerySuggested += value; 
      } 
      remove 
      { 
       if (this._canExecuteCallback != null) 
        CommandManager.RequerySuggested -= value; 
      } 
     } 

     /// <summary> 
     /// Defines the method to be called when the command is invoked. 
     /// </summary> 
     /// <param name="parameter">Data used by the command. If the command does not require data to be passed, this object can be set to <see langword="null"/>.</param> 
     public void Execute(object parameter) 
     { 
      this._executeCallback((T)parameter); 
     } 

     #endregion // ICommand Members 

    } 
}