Binding ConvererParameter

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WPF中ConverterParameter不可以绑定，可以通过如下扩展来实现ConverterParameter的Binding:

1.自定义ConverterBindableBinding和MultiValueConverterAdapter：

namespace TTSControl.UtilityClasses
{
    public class ConverterBindableBinding : MarkupExtension
    {
        public Binding Binding { get; set; }

        public IValueConverter Converter { get; set; }

        public Binding ConverterParameterBinding { get; set; }

        public Binding ConverterBinding { get; set; }

        public override object ProvideValue(IServiceProvider serviceProvider)
        {
            MultiBinding multiBinding = new MultiBinding();
            multiBinding.Bindings.Add(Binding);
            multiBinding.Bindings.Add(ConverterParameterBinding);
            if (ConverterBinding != null) multiBinding.Bindings.Add(ConverterBinding);
            MultiValueConverterAdapter adapter = new MultiValueConverterAdapter();
            adapter.Converter = Converter;
            multiBinding.Converter = adapter;
            return multiBinding.ProvideValue(serviceProvider);
        }
    }
}

namespace TTSControl.UtilityClasses
{
    [ContentProperty("Converter")]
    public class MultiValueConverterAdapter : IMultiValueConverter
    {
        public IValueConverter Converter { get; set; }

        #region IMultiValueConverter Members

        private object lastParameter;
        private IValueConverter lastConverter;

        public object Convert(object[] values, Type targetType, object parameter, System.Globalization.CultureInfo culture)
        {
            lastConverter = Converter;
            if (values.Length > 1) lastParameter = values[1];
            if (values.Length > 2) lastConverter = (IValueConverter)values[2];
            if (Converter == null) return values[0];
            return Converter.Convert(values[0], targetType, lastParameter, culture);
        }

        public object[] ConvertBack(object value, Type[] targetTypes, object parameter, System.Globalization.CultureInfo culture)
        {
            if (lastConverter == null) return new object[] { value };
            return new object[] { lastConverter.ConvertBack(value, targetTypes[0], lastParameter, culture) };
        }

        #endregion

    }
}

2。在xaml中绑定：

xmlns:uti="clr-namespace:TTSControl.UtilityClasses"        

 
 Binding="{Binding PermissionKey}" Converter="{StaticResource permissionValueConverter}"ConverterParameterBinding="{Binding UserName}" />
 

3。在自定义Converter类中获取绑定数据：

    internal class PermissionValueConverter : DependencyObject, IValueConverter, IMultiValueConverter
    {
       
        // For testing of converter properties, we derice from DependencyObject and add a dependency property.

        public String UserName
        {
            get { return (String)GetValue(UserNameProperty); }
            set { SetValue(UserNameProperty, value); }
        }

        // Using a DependencyProperty as the backing store for ConcatSign.  This enables animation, styling, binding, etc...
        public static readonly DependencyProperty UserNameProperty =
            DependencyProperty.Register("UserName", typeof(String), typeof(PermissionValueConverter), new UIPropertyMetadata(null));

        #region IValueConverter Members

        public object Convert(object value, Type targetType, object parameter, System.Globalization.CultureInfo culture)
        {
            string permissionKey = (string)value;
            string  userName= (string)parameter;

            List> PermissionValues = new List>();
            PermissionValues = Database.GetPermissionValue(Properties.Settings.Default.gLanguage, userName, permissionKey);
            return PermissionValues;
  
        }

        public object ConvertBack(object value, Type targetType, object parameter, System.Globalization.CultureInfo culture)
        {
            throw new NotImplementedException();
        }

        #endregion

        #region IMultiValueConverter Members

        public object Convert(object[] values, Type targetType, object parameter, System.Globalization.CultureInfo culture)
        {
            return Convert(values[0], targetType, values[1], culture);
        }

        public object[] ConvertBack(object value, Type[] targetTypes, object parameter, System.Globalization.CultureInfo culture)
        {
            return new object[] { ConvertBack(value, targetTypes[0], parameter, culture) };
        }

        #endregion

    }

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Binding ConvererParameter

标签：style   class   tar   ext   color   get   

原文地址：http://www.cnblogs.com/eric_ibm/p/3784299.html