web api core全局拦截 200 的结果进行文本替换等逻

方法1 中间件实现

using System.IO;
using System.Threading.Tasks;
using Microsoft.AspNetCore.Http;

public class TextReplaceMiddleware
{
    private readonly RequestDelegate _next;

    public TextReplaceMiddleware(RequestDelegate next)
    {
        _next = next;
    }

    public async Task InvokeAsync(HttpContext context)
    {
        // 暂存原始响应内容
        var originalBodyStream = context.Response.Body;
        using (var responseBody = new MemoryStream())
        {
            // 替换响应内容
            context.Response.Body = responseBody;

            await _next(context);

            // 恢复原始响应内容
            context.Response.Body.Seek(0, SeekOrigin.Begin);
            var body = await new StreamReader(context.Response.Body).ReadToEndAsync();
            body = body.Replace("oldText", "newText");
            context.Response.Body.Seek(0, SeekOrigin.Begin);

            // 将修改后的响应内容写回原始响应流中
            await context.Response.Body.WriteAsync(Encoding.UTF8.GetBytes(body));
            context.Response.Body = originalBodyStream;
        }
    }
}

public void Configure(IApplicationBuilder app, IWebHostEnvironment env)
{
    // ...

    app.UseMiddleware<TextReplaceMiddleware>();

    // ...
}

方法2

using System.IO;
using System.Text;
using System.Threading.Tasks;
using Microsoft.AspNetCore.Mvc.Filters;

public class TextReplaceFilter : IAsyncActionFilter
{
    public async Task OnActionExecutionAsync(ActionExecutingContext context, ActionExecutionDelegate next)
    {
        var resultContext = await next();

        // 判断响应是否为200
        if (resultContext.HttpContext.Response.StatusCode == 200)
        {
            // 暂存原始响应内容
            var originalBodyStream = resultContext.HttpContext.Response.Body;
            using (var responseBody = new MemoryStream())
            {
                // 替换响应内容
                resultContext.HttpContext.Response.Body = responseBody;

                // 读取响应内容并替换
                var body = await new StreamReader(originalBodyStream).ReadToEndAsync();
                body = body.Replace("oldText", "newText");

                // 将修改后的响应内容写回原始响应流中
                await resultContext.HttpContext.Response.Body.WriteAsync(Encoding.UTF8.GetBytes(body));
                resultContext.HttpContext.Response.Body = originalBodyStream;
            }
        }
    }
}

调整controller

[ServiceFilter(typeof(TextReplaceFilter))]
public class MyController : ControllerBase
{
    // ...
}

另外

//builder.Services.AddSingleton<CollectAlertActionFilter>();//单例
builder.Services.AddScoped<CollectAlertActionFilter>();

还有一些坑，kenel需要禁用缓冲区最后换了一种办法

      public async Task OnActionExecutionAsync(ActionExecutingContext context, ActionExecutionDelegate next)
       {
           var resultContext = await next();

           if (resultContext.Result is ObjectResult objectResult)
           {
               var response = context.HttpContext.Response;
               if (objectResult.StatusCode == 200|| response.StatusCode==200)
               {
                   var responseString = objectResult.Value.ToString();

objectResult.StatusCode是空的所以还是用之前的那种判断

获取controller

                        var actionDescriptor = context.ActionDescriptor as ControllerActionDescriptor;
                        var controllerName = actionDescriptor?.ControllerName;
                        var actionName = actionDescriptor?.ActionName;

                        // 获取Controller的描述信息
                        var controllerType = actionDescriptor?.ControllerTypeInfo.AsType();
                        var controllerName1 = context.RouteData.Values["controller"];
                        var actionName1 = context.RouteData.Values["action"];

获取displayName
经过测试 发现里面有多个displayname,默认的也存在,根据条件进行过滤吧

       DisplayNameAttribute displayName = context.ActionDescriptor.GetProperty<DisplayNameAttribute>();
                        methodDescriptor= actionDescriptor.MethodInfo.GetCustomAttribute<DisplayNameAttribute>()?.DisplayName;
                        var displayNameAttribute = context.ActionDescriptor.EndpointMetadata
          .OfType<DisplayNameAttribute>()
          .LastOrDefault()?.DisplayName;