MyAvaloniaDemo/Converters/StringConverters.cs

using Avalonia.Data.Converters;
using Avalonia.Media;
using HeroIconsAvalonia.Enums;
using System;
using System.Globalization;

namespace MyAvaloniaApp.Converters;

/// <summary>
/// 字符串转换器类
/// </summary>
public static class StringConverters
{
    /// <summary>
    /// 角色到颜色的转换器
    /// </summary>
    public static readonly IValueConverter RoleToColorConverter = new RoleToColorConverter();

    /// <summary>
    /// 状态到颜色的转换器
    /// </summary>
    public static readonly IValueConverter StatusToColorConverter = new StatusToColorConverter();

    /// <summary>
    /// 空值到布尔值的转换器
    /// </summary>
    public static readonly IValueConverter NullToBoolConverter = new NullToBoolConverter();

    /// <summary>
    /// 布尔值到图标类型的转换器
    /// </summary>
    public static readonly IValueConverter BoolToIconConverter = new BoolToIconConverter();
}

/// <summary>
/// 角色到颜色转换器
/// </summary>
public class RoleToColorConverter : IValueConverter
{
    public object? Convert(object? value, Type targetType, object? parameter, CultureInfo culture)
    {
        if (value is string role)
        {
            return role switch
            {
                "管理员" => new SolidColorBrush(Color.FromRgb(220, 53, 69)), // 红色
                "编辑" => new SolidColorBrush(Color.FromRgb(255, 193, 7)),   // 黄色
                "用户" => new SolidColorBrush(Color.FromRgb(40, 167, 69)),   // 绿色
                _ => new SolidColorBrush(Color.FromRgb(108, 117, 125))       // 灰色
            };
        }
        return new SolidColorBrush(Color.FromRgb(108, 117, 125));
    }

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

/// <summary>
/// 状态到颜色转换器
/// </summary>
public class StatusToColorConverter : IValueConverter
{
    public object? Convert(object? value, Type targetType, object? parameter, CultureInfo culture)
    {
        if (value is string status)
        {
            return status switch
            {
                "在线" => new SolidColorBrush(Color.FromRgb(40, 167, 69)),   // 绿色
                "离线" => new SolidColorBrush(Color.FromRgb(108, 117, 125)), // 灰色
                "忙碌" => new SolidColorBrush(Color.FromRgb(220, 53, 69)),   // 红色
                _ => new SolidColorBrush(Color.FromRgb(108, 117, 125))       // 灰色
            };
        }
        return new SolidColorBrush(Color.FromRgb(108, 117, 125));
    }

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

/// <summary>
/// 空值到布尔值转换器
/// </summary>
public class NullToBoolConverter : IValueConverter
{
    public object? Convert(object? value, Type targetType, object? parameter, CultureInfo culture)
    {
        return value != null;
    }

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

/// <summary>
/// 布尔值到图标类型转换器
/// </summary>
public class BoolToIconConverter : IValueConverter
{
    public object? Convert(object? value, Type targetType, object? parameter, CultureInfo culture)
    {
        if (value is bool isExpanded)
        {
            return isExpanded ? IconType.ChevronDown : IconType.ChevronRight;
        }
        return IconType.ChevronRight;
    }

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