单例模式
using System;
using System.Globalization;
using System.Windows.Data;
namespace YourNamespace
{
public class HalfWidthConverter : IValueConverter
{
// 静态实例
public static readonly HalfWidthConverter Instance = new HalfWidthConverter();
// 私有构造函数，防止外部直接实例化
private HalfWidthConverter()
{
}
public object Convert(object value, Type targetType, object parameter, CultureInfo culture)
{
if (value is double width)
{
return width / 2.0;
}
return 0.0; // 如果输入值不是double类型，返回0
}
public object ConvertBack(object value, Type targetType, object parameter, CultureInfo culture)
{
if (value is double halfWidth)
{
return halfWidth * 2.0; // 将一半的宽度转换回原始宽度
}
return 0.0; // 如果输入值不是double类型，返回0
}
}
}
单例模式不用资源
<Window x:Class="YourNamespace.MainWindow"
xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
xmlns:local="clr-namespace:YourNamespace"
Title="MainWindow" Height="350" Width="525">
<Grid x:Name="parentGrid">
<TextBox Width="{Binding ActualWidth, ElementName=parentGrid, Converter={x:Static local:HalfWidthConverter.Instance}}" />
</Grid>
</Window>
不用单例则
<TextBox Width="{Binding ElementName=parentGrid, Path=ActualWidth, Converter={StaticResource HalfWidthConverter}}" />
是staticresource
资源存放位置
binding 属性，elementname/source/relativesource ，converter
source x static
relativesource=relativesoure self/findancestor ancestortype
