MultiBinding(多路Binding)

有时候UI要需要显示的信息由不止一个数据来源决定，这个时候就需要用到MultiBinding

用一个小例子介绍一下

• 第一、二个TextBox输入用户名，要求内容一致
• 第三、四个TextBox输入用户名E-Mail，要求内容一致
• 当TextBox的内容全部符合要求的时候，Button可用

 UI的XAML代码：

<Window x:Class="Wpf.SetMultiBinding"xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"xmlns:d="http://schemas.microsoft.com/expression/blend/2008"xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006"xmlns:local="clr-namespace:Wpf"mc:Ignorable="d"Title="SetMultiBinding" Height="200" Width="400"><StackPanel Background="LightBlue"><TextBox x:Name="textBox1" Height="23" Margin="5"/><TextBox x:Name="textBox2" Height="23" Margin="5"/><TextBox x:Name="textBox3" Height="23" Margin="5"/><TextBox x:Name="textBox4" Height="23" Margin="5"/><Button x:Name="button1" Content="Submit" Width="80" Margin="5"/></StackPanel>
</Window>

窗口构造器的代码：

using System.Windows;
using System.Windows.Controls;
using System.Windows.Data;
namespace Wpf
{/// <summary>/// SetMultiBinding.xaml 的交互逻辑/// </summary>public partial class SetMultiBinding : Window{public SetMultiBinding(){InitializeComponent();this.SetMultiBinding1();}private void SetMultiBinding1(){//准备基础BindingBinding b1 = new Binding("Text") { Source = this.textBox1 };Binding b2 = new Binding("Text") { Source = this.textBox2 };Binding b3 = new Binding("Text") { Source = this.textBox3 };Binding b4 = new Binding("Text") { Source = this.textBox4 };//准备MultiBindingMultiBinding mb = new MultiBinding() { Mode = BindingMode.OneWay};mb.Bindings.Add(b1);mb.Bindings.Add(b2);mb.Bindings.Add(b3);mb.Bindings.Add(b4);mb.Converter = new LogonMultiBindingConverter();this.button1.SetBinding(Button.IsEnabledProperty, mb);}}
}

Converter代码： 

using System;
using System.Linq;
using System.Windows.Data;
using System.Globalization;
namespace Wpf
{public class LogonMultiBindingConverter :IMultiValueConverter{public object Convert(object[] values,Type tragetType,object parameter,CultureInfo culture){if (!values.Cast<string>().Any(text => string.IsNullOrEmpty(text))&& values[0].ToString() == values[1].ToString()&& values[2].ToString() == values[3].ToString()){ return true;}return false;}public object[] ConvertBack(object values, Type[] tragetType, object parameter, CultureInfo culture){throw new NotImplementedException();}}}

效果图：主要看一下button！