如何将参数传递给事件触发器wpf中的方法

Question

实际上，我试图在Xaml文件的ViewModel中存在的方法UpdateWord（object obj）中传递word文档的名称。这样它就会打开word文档。

<Button Content="Show Word" Width="100" Height="25" Margin="128,70,22,37">
    <i:Interaction.Triggers>
            <i:EventTrigger EventName="Click">
                <si:CallDataMethod Method="UpdateWord"/>     
                <si:SetProperty TargetName="LayoutRoot" 
        PropertyName="Background" Value="PaleGoldenrod"/>
     </i:EventTrigger>
  </i:Interaction.Triggers>          

ViewModel：

public void UpdateWord(Object obj)
{

   //Do Something ..... ;
}

Answer 1

你可以这样做

  <i:EventTrigger EventName="Click">
        <cmd:EventToCommand Command="{Binding UpdateWord}"
            PassEventArgsToCommand="True" />
    </i:EventTrigger>

你可以参考这篇文章了解更多deatil：http://weblogs.asp.net/alexeyzakharov/silverlight-commands-hacks-passing-eventargs-as-commandparameter-to-delegatecommand-triggered-by-eventtrigger

Answer 2

有多种方法可以执行此操作，请查看here：

1. 使用WPF工具。最简单的

添加命名空间：

• System.Windows.Interactivitiy
• Microsoft.Expression.Interactions

XAML：

<Window>
    xmlns:wi="clr-namespace:System.Windows.Interactivity;assembly=System.Windows.Interactivity"
    xmlns:ei="http://schemas.microsoft.com/expression/2010/interactions">

    <wi:Interaction.Triggers>
        <wi:EventTrigger EventName="SelectionChanged">
            <ei:CallMethodAction
                TargetObject="{Binding}"
                MethodName="ShowCustomer"/>
        </wi:EventTrigger>
    </wi:Interaction.Triggers>
</Window>

代码：

public void ShowCustomer()
{
    // Do something.
}

1. 使用MVVMLight。最困难但最佳的做法

安装GalaSoft NuGet包。



获取名称空间：

• System.Windows.Interactivity
• GalaSoft.MvvmLight.Platform

XAML

<Window>
    xmlns:wi="clr-namespace:System.Windows.Interactivity;assembly=System.Windows.Interactivity"
    xmlns:cmd="http://www.galasoft.ch/mvvmlight">

    <wi:Interaction.Triggers>
       <wi:EventTrigger EventName="Navigated">
           <cmd:EventToCommand Command="{Binding NavigatedEvent}"
               PassEventArgsToCommand="True" />
       </wi:EventTrigger>
    </wi:Interaction.Triggers>
</Window>

代表代码：Source

你必须得到Prism MVVM NuGet包。



using Microsoft.Practices.Prism.Commands;

// With params.
public DelegateCommand<string> CommandOne { get; set; }
// Without params.
public DelegateCommand CommandTwo { get; set; }

public MainWindow()
{
    InitializeComponent();

    // Must initialize the DelegateCommands here.
    CommandOne = new DelegateCommand<string>(executeCommandOne);
    CommandTwo = new DelegateCommand(executeCommandTwo);
}

private void executeCommandOne(string param)
{
    // Do something here.
}

private void executeCommandTwo()
{
    // Do something here.
}

没有DelegateCommand的代码：Source

using GalaSoft.MvvmLight.CommandWpf

public MainWindow()
{
    InitializeComponent();

    CommandOne = new RelayCommand<string>(executeCommandOne);
    CommandTwo = new RelayCommand(executeCommandTwo);
}

public RelayCommand<string> CommandOne { get; set; }

public RelayCommand CommandTwo { get; set; }

private void executeCommandOne(string param)
{
    // Do something here.
}

private void executeCommandTwo()
{
    // Do something here.
}

1. 使用Telerik EventToCommandBehavior。您必须下载NuGet Package。这是一个选择。

XAML：

<i:Interaction.Behaviors>
    <telerek:EventToCommandBehavior
         Command="{Binding DropCommand}"
         Event="Drop"
         PassArguments="True" />
</i:Interaction.Behaviors>

代码：

public ActionCommand<DragEventArgs> DropCommand { get; private set; }

this.DropCommand = new ActionCommand<DragEventArgs>(OnDrop);

private void OnDrop(DragEventArgs e)
{
    // Do Something
}