北京html5网站建设新冠病毒最新消息

工业控制中，经常会需要把一个bool  型输入信号的状态显示在面板上，使用wpf 绑定的办法，可简洁实现：

实现步骤：

1，定义类：

using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Linq;
using System.Runtime.CompilerServices;
using System.Text;
using System.Threading.Tasks;namespace WpfAppBoolBinding
{public class MainViewModel : INotifyPropertyChanged{private bool _myProperty;public bool MyProperty{get { return _myProperty; }set{if (_myProperty != value){_myProperty = value;OnPropertyChanged();}}}public event PropertyChangedEventHandler PropertyChanged;protected virtual void OnPropertyChanged([CallerMemberName] string propertyName = ""){if (this.PropertyChanged != null){this.PropertyChanged(this, new PropertyChangedEventArgs(propertyName));}}}public class TestViewModel{public MainViewModel MainView { get; set; }public int couter { get; set; }}
}

2，定义bool  类型转换器：

using System;
using System.Collections.Generic;
using System.Globalization;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
using System.Windows.Data;
using System.Windows.Media;namespace WpfAppBoolBinding
{[ValueConversion(typeof(bool), typeof(Brush))]public class BooleanToBrushConverter : IValueConverter{public object Convert(object value, Type targetType, object parameter, CultureInfo culture){return (bool)value ? Brushes.Green : Brushes.Red;}public object ConvertBack(object value, Type targetType, object parameter, CultureInfo culture){throw new NotImplementedException();}}}

3，xml 实现：

<Window x:Class="WpfAppBoolBinding.MainWindow"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:WpfAppBoolBinding" mc:Ignorable="d"Title="MainWindow" Height="450" Width="800"><Window.Resources><local:BooleanToBrushConverter x:Key="BooleanToBrushConverter"/></Window.Resources><Grid><StackPanel HorizontalAlignment="Center" VerticalAlignment="Center"><Ellipse Width="50" Height="50" Fill="{Binding MainView.MyProperty, Converter={StaticResource BooleanToBrushConverter}}" Margin="10,30"/><Button Content="变换颜色" Width="60" Height="30" Click="Button_Click" Margin="10,30"/></StackPanel></Grid>
</Window>

4，进行Datacontex 绑定：

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
using System.Windows;
using System.Windows.Controls;
using System.Windows.Data;
using System.Windows.Documents;
using System.Windows.Input;
using System.Windows.Media;
using System.Windows.Media.Imaging;
using System.Windows.Navigation;
using System.Windows.Shapes;namespace WpfAppBoolBinding
{/// <summary>/// MainWindow.xaml 的交互逻辑/// </summary>public partial class MainWindow : Window{TestViewModel testViewModel = new TestViewModel();public MainWindow(){InitializeComponent();testViewModel.MainView = new MainViewModel();DataContext = testViewModel;}private void Button_Click(object sender, RoutedEventArgs e){testViewModel.MainView.MyProperty = !testViewModel.MainView.MyProperty;}}
}