Asp.Net Core 自定义设置Http缓存处理-白红宇

Asp.Net Core 自定义设置Http缓存处理

阅读量：5144 次

发布时间：2019-06-13

本文共 2144 字，大约阅读时间需要 7 分钟。

一、使用中间件拦截请求自定义输出文件

输出前自定义指定响应头

public class OuterImgMiddleware    {        public static string RootPath { get; set; } //配置文件读取绝对位置        private readonly RequestDelegate _next;        public OuterImgMiddleware(RequestDelegate next, IHostingEnvironment env)        {            _next = next;        }        public async Task Invoke(HttpContext context)        {            var path = context.Request.Path.ToString();            var headersDictionary = context.Request.Headers;            if (context.Request.Method == "GET")                if (!string.IsNullOrEmpty(path) && path.Contains("/upload/logo"))                {                    var unauthorizedImagePath = RootPath + path;                    context.Response.ContentType = "image/jpeg";                    context.Response.Headers["Cache-Control"] = "public"; //指定客户端，服务器都处理缓存                    int length = path.LastIndexOf(".") - path.LastIndexOf("/") - 1;                    context.Response.Headers["Etag"] = path.Substring(path.LastIndexOf("/") + 1, length);                    context.Response.Headers["Last-Modified"] = new DateTime(2018).ToString("r");                    FileInfo file = new FileInfo(unauthorizedImagePath);                    context.Response.Headers["Content-Length"] = file.Length.ToString();                    context.Response.Headers["Accept-Ranges"] = "bytes";                    //如果Transfer-Encoding =chunked 没有指定的话，SendFile 前台解析事变                    //指定Content-Length 可以是 chunked 分块实效                    //context.Response.Headers["Transfer-Encoding"] = "";                    //Http 1.0 是使用Expires 属性                    //context.Response.Headers["Expires"] = DateTime.Now.AddMonths(1).ToString("r");                    await context.Response.SendFileAsync(unauthorizedImagePath);                    return;                }            await _next(context);        }    }    public static class MvcExtensions    {        public static IApplicationBuilder UseOutImg(this IApplicationBuilder builder)        {            return builder.UseMiddleware
     
      ();        }    }