使用 IMultiValueConverter 将多个参数传递给 Command

可以使用 MultiBinding 以非常简单的 IMultiValueConverter 将多个绑定值作为 CommandParameter 传递：

namespace MyProject.Converters
{
    public class Converter_MultipleCommandParameters : MarkupExtension, IMultiValueConverter
    {
        public object Convert(object[] values, Type targetType, object parameter, CultureInfo culture)
        {
            return values.ToArray();
        }
        public object[] ConvertBack(object value, Type[] targetTypes, object parameter, CultureInfo culture)
        {
            throw new NotSupportedException();
        }

        private static Converter_MultipleCommandParameters _converter = null;

        public override object ProvideValue(IServiceProvider serviceProvider)
        {
            if (_converter == null) _converter = new Converter_MultipleCommandParameters();
            return _converter;
        }

        public Converter_MultipleCommandParameters()
            : base()
        {
        }
    }
}

使用转换器：

1. 示例实现 - 执行 SomeCommand 时调用的方法（ 注意：DelegateCommand 是 ICommand 的一个实现，在本例中未提供 ）：

    private ICommand _SomeCommand;
    public ICommand SomeCommand
    {
        get { return _SomeCommand ?? (_SomeCommand = new DelegateCommand(a => OnSomeCommand(a))); }
    }
   
    private void OnSomeCommand(object item)
    {
        object[] parameters = item as object[];
   
        MessageBox.Show(
            string.Format("Execute command: {0}\nParameter 1: {1}\nParamter 2: {2}\nParamter 3: {3}",
            "SomeCommand", parameters[0], parameters[1], parameters[2]));
    }
   

2. 命名空间

xmlns：转换器= “CLR-名称空间：MyProject.Converters;装配= MyProject 的”

3. 示例在绑定中使用此转换器

   <Button Width="150" Height="23" Content="Execute some command" Name="btnTestSomeCommand"
        Command="{Binding Path=SomeCommand}" >
        <Button.CommandParameter>
            <MultiBinding Converter="{converters:Converter_MultipleCommandParameters}">
                <Binding RelativeSource="{RelativeSource Self}" Path="IsFocused"/>
                <Binding RelativeSource="{RelativeSource Self}" Path="Name"/>
                <Binding RelativeSource="{RelativeSource Self}" Path="ActualWidth"/>
            </MultiBinding>
        </Button.CommandParameter>
    </Button>