如何在wpf中加载窗口时触发命令

要避免视图中的代码落后,请使用交互库(System.Windows.Interactivity dll,您可以从Microsoft免费下载-Expression Blend也提供了该库)。

<ia:Interaction.Triggers>
    <ia:EventTrigger EventName="Loaded">
        <custombehaviors:CommandAction Command="{Binding ShowMessage}" Parameter="I am loaded"/>
    </ia:EventTrigger>
</ia:Interaction.Triggers>

CommandAction(也使用System.Windows.Interactivity)可以如下所示:

public class CommandAction : TriggerAction<UIElement>
{
    public static DependencyProperty CommandProperty = DependencyProperty.Register("Command", typeof(ICommand), typeof(CommandAction), null);
    public ICommand Command
    {
        get
        {
            return (ICommand)GetValue(CommandProperty);
        }
        set
        {
            SetValue(CommandProperty, value);
        }
    }


    public static DependencyProperty ParameterProperty = DependencyProperty.Register("Parameter", typeof(object), typeof(CommandAction), null);
    public object Parameter
    {
        get
        {
            return GetValue(ParameterProperty);
        }
        set
        {
            SetValue(ParameterProperty, value);

        }
    }

    protected override void Invoke(object parameter)
    {
        Command.Execute(Parameter);            
    }
}

    private void Window_Loaded(object sender, RoutedEventArgs e)
    {
       ApplicationCommands.New.Execute(null, targetElement); 
       // or this.CommandBindings[0].Command.Execute(null); 
    }

和xaml

    Loaded="Window_Loaded"

AttachedCommandBehavior V2 aka ACB 它甚至支持多个事件到命令绑定,

下面是一个非常基本的使用示例:

<Window x:Class="Example.YourWindow"
        xmlns:local="clr-namespace:AttachedCommandBehavior;assembly=AttachedCommandBehavior"
        local:CommandBehavior.Event="Loaded"
        local:CommandBehavior.Command="{Binding DoSomethingWhenWindowIsLoaded}"
        local:CommandBehavior.CommandParameter="Some information"
/>

xmlns:i="http://schemas.microsoft.com/xaml/behaviors"

像这样利用它:

<i:Interaction.Triggers>
    <i:EventTrigger EventName="Loaded">
        <i:InvokeCommandAction Command="{Binding CommandInViewModel}"/>
    </i:EventTrigger>
</i:Interaction.Triggers>