Refactor Circles component to use reflection-based attribute extraction with caching

[Copilot]

Summary By Copilot

Replaced manual AttributeItem array maintenance with reflection-based automatic extraction from Circle component parameters. Implemented global static cache for performance.

Changes

AttributeItem class (src/BootstrapBlazor.Server/Data/AttributeItem.cs)

• Added Version property for XML documentation version tags

ComponentAttributeCacheService (src/BootstrapBlazor.Server/Services/ComponentAttributeCacheService.cs)

• Global ConcurrentDictionary cache for component attribute metadata
• Reflection-based extraction of [Parameter] attributes
• XML documentation parsing: summary, version (<para><version>), default values
• Automatic enum value list generation
• Security hardening: XXE prevention via XmlReaderSettings, assembly location validation, specific exception handling

Circles.razor.cs (src/BootstrapBlazor.Server/Components/Samples/Circles.razor.cs)

• Replaced 52-line manual array with single reflection call:

private AttributeItem[] GetAttributes()
{
    return ComponentAttributeCacheService.GetAttributes(typeof(BootstrapBlazor.Components.Circle));
}

BootstrapBlazor.csproj (src/BootstrapBlazor/BootstrapBlazor.csproj)

• Enabled GenerateDocumentationFile for XML comments

Screenshot

Attributes table correctly displays all Circle component parameters via reflection: Value, Width, StrokeWidth, Color (with enum values), ShowProgress, ChildContent, Id, AdditionalAttributes.

Regression?

• Yes
• No

Risk

• High
• Medium
• Low

Isolated change to demo component attribute display. No API changes, backward compatible. Cache invalidation available via ClearCache().

Verification

• Manual (required)
• Automated

Packaging changes reviewed?

• Yes
• No
• N/A

☑️ Self Check before Merge

⚠️ Please check all items below before review. ⚠️

• Doc is updated/provided or not needed
• Demo is updated/provided or not needed
• Merge the latest code from the main branch

Original prompt

目标

重构 Circles 示例组件,从手动维护 AttributeItem 列表改为使用反射自动获取 Circle 组件的参数信息,并通过全局静态字典缓存提升性能。

需要实现的功能

1. 扩展 AttributeItem 类添加 Version 属性

文件:src/BootstrapBlazor.Server/Data/AttributeItem.cs

在 AttributeItem 类中添加一个新的 Version 属性:

/// <summary>
/// 获得/设置 版本
/// </summary>
[DisplayName("版本")]
public string Version { get; set; } = "";

2. 创建全局静态缓存服务

创建新文件:src/BootstrapBlazor.Server/Services/ComponentAttributeCacheService.cs

实现一个全局静态字典缓存服务,用于缓存组件的 AttributeItem 列表:

using System.Collections.Concurrent;
using System.ComponentModel;
using System.Reflection;
using System.Xml.Linq;
using BootstrapBlazor.Server.Data;
using Microsoft.AspNetCore.Components;

namespace BootstrapBlazor.Server.Services;

/// <summary>
/// 组件属性缓存服务
/// </summary>
public static class ComponentAttributeCacheService
{
    private static readonly ConcurrentDictionary<Type, AttributeItem[]> _cache = new();

    /// <summary>
    /// 获取组件的 AttributeItem 列表(带缓存)
    /// </summary>
    public static AttributeItem[] GetAttributes(Type componentType)
    {
        return _cache.GetOrAdd(componentType, type =>
        {
            var attributes = new List<AttributeItem>();
            var properties = type.GetProperties(BindingFlags.Public | BindingFlags.Instance)
                .Where(p => p.GetCustomAttribute<ParameterAttribute>() != null);

            foreach (var property in properties)
            {
                var item = new AttributeItem
                {
                    Name = property.Name,
                    Type = GetFriendlyTypeName(property.PropertyType),
                    Description = GetSummary(property) ?? "",
                    DefaultValue = GetDefaultValue(property) ?? "",
                    ValueList = GetValueList(property) ?? "",
                    Version = GetVersion(property) ?? ""
                };
                attributes.Add(item);
            }

            return attributes.ToArray();
        });
    }

    /// <summary>
    /// 从 XML 注释获取 summary
    /// </summary>
    private static string? GetSummary(PropertyInfo property)
    {
        var xmlDoc = GetXmlDocumentation(property.DeclaringType?.Assembly);
        if (xmlDoc == null) return null;

        var memberName = $"P:{property.DeclaringType?.FullName}.{property.Name}";
        var element = xmlDoc.Descendants("member")
            .FirstOrDefault(x => x.Attribute("name")?.Value == memberName);

        return element?.Element("summary")?.Value.Trim();
    }

    /// <summary>
    /// 从 XML 注释的 para version 节点获取版本信息
    /// </summary>
    private static string? GetVersion(PropertyInfo property)
    {
        var xmlDoc = GetXmlDocumentation(property.DeclaringType?.Assembly);
        if (xmlDoc == null) return null;

        var memberName = $"P:{property.DeclaringType?.FullName}.{property.Name}";
        var element = xmlDoc.Descendants("member")
            .FirstOrDefault(x => x.Attribute("name")?.Value == memberName);

        // 查找 <para><version>10.0.0</version></para>
        var versionElement = element?.Descendants("para")
            .SelectMany(p => p.Elements("version"))
            .FirstOrDefault();

        return versionElement?.Value.Trim();
    }

    /// <summary>
    /// 获取默认值
    /// </summary>
    private static string? GetDefaultValue(PropertyInfo property)
    {
        var defaultValueAttr = property.GetCustomAttribute<DefaultValueAttribute>();
        if (defaultValueAttr != null)
        {
            return defaultValueAttr.Value?.ToString() ?? "";
        }

        // 从 XML 注释中提取 DefaultValue
        var xmlDoc = GetXmlDocumentation(property.DeclaringType?.Assembly);
        if (xmlDoc == null) return null;

        var memberName = $"P:{property.DeclaringType?.FullName}.{property.Name}";
        var element = xmlDoc.Descendants("member")
            .FirstOrDefault(x => x.Attribute("name")?.Value == memberName);

        var defaultElement = element?.Element("value");
        return defaultElement?.Value.Trim();
    }

    /// <summary>
    /// 获取可选值列表
    /// </summary>
    private static string? GetValueList(PropertyInfo property)
    {
        // 如果是枚举类型,返回枚举值
        if (property.PropertyType.IsEnum)
        {
            return string.Join(" / ", Enum.GetNames(property.PropertyType));
        }

        return "";
    }

    /// <summary>
    /// 获取友好的类型名称
    /// </summary>
    private static string GetFriendlyTypeName(Type type)
    {
        if (type.IsGenericType)
        {
            var genericTypeName = type.GetGenericTypeDefinition().Name;
            genericTypeName = genericTypeName.Substring(0, genericTypeName.IndexOf('`'));
            var genericArgs = string.Join(", ", type.GetGenericArguments().Select(GetFriendlyTypeName));
            return $"{genericTypeName}<{genericArgs}>";
        }

        return type.Name switch
        {
            "Int32" => "int",
            "String" => "string",
            "Boolean" => "bool",
            "Double" => "double...

</details>



<!-- START COPILOT CODING AGENT SUFFIX -->

*This pull request was created from Copilot chat.*
>

<!-- START COPILOT CODING AGENT TIPS -->
---

💬 We'd love your input! Share your thoughts on Copilot coding agent in our [2 minute survey](https://gh.io/copilot-coding-agent-survey).

[bb-auto]

Thanks for your PR, @copilot. Someone from the team will get assigned to your PR shortly and we'll get it reviewed.