57 lines
1.8 KiB
C#
57 lines
1.8 KiB
C#
using System;
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using System.Collections.Generic;
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using System.Globalization;
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using System.Linq;
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using System.Text;
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using System.Text.RegularExpressions;
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using System.Threading.Tasks;
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using System.Windows;
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using System.Windows.Data;
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namespace WpfAppTest
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{
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internal class UnitConverter : IValueConverter
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{
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private string DefaultUnit { get; set; } = "mm";
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public object Convert(object value, Type targetType, object parameter, CultureInfo culture)
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{
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if (value == null)
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return null;
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if (value is double d)
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{
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string unit = parameter as string ?? DefaultUnit;
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// 使用StringFormat时，value会先被格式化，这里直接拼接单位
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return $"{d.ToString(culture)} {unit}";
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}
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return value;
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}
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public object ConvertBack(object value, Type targetType, object parameter, CultureInfo culture)
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{
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if (value is string str)
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{
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// 提取纯数字字符串（允许中间态如 '1.', '-.'）
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str = str.Trim();
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var match = Regex.Match(str, @"[-+]?[0-9]*\.?[0-9]*");
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if (match.Success)
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{
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string numberPart = match.Value;
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// 处理中间态输入，允许返回未完成的文本（让 UI 不抖动）
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if (string.IsNullOrEmpty(numberPart) || numberPart.EndsWith("-") || numberPart.EndsWith(".") || numberPart.EndsWith("-."))
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return DependencyProperty.UnsetValue;
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if (double.TryParse(numberPart, NumberStyles.Any, culture, out double result))
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return result;
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}
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}
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return DependencyProperty.UnsetValue;
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}
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}
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}
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