说到URL重写就不得不提URL重定向.
URL重定向
URL重定向是客户端操作,指示客户端访问另一个地址的资源.这需要往返服务器,并且当客户端对资源发出请求时,返回客户端的重定向URL会出现在浏览器的地址栏中.
将请求重定向到不同的URL时,可指示重定向是永久的还是临时的.如果是永久的,则使用"301"状态码.收到"301"状态码时,客户端可能会缓存.如果是临时的,则使用"302"状态码,以使客户端将来不应存储和重用重定向URL.
示例:
新建一个WebAPI项目;新增一个 TestController 控制器;在 Startup 类的 Configure 方法中增加如下代码:
???????public void Configure(IApplicationBuilder app, IHostingEnvironment env) ???????{ ???????????...other codes ???????????var options = new RewriteOptions(); ???????????//options.AddRedirect("^redirect/(.*)", "api/test");//默认状态码为 302 ???????????options.AddRedirect("^redirect/(.*)", "api/test", 301); ???????????app.UseRewriter(options); ???????????app.Run(async context => ???????????????{ ???????????????????//注意重定向和重写URL两种情况下,浏览器地址栏和页面显示的 URL 的区别. ???????????????????await context.Response.WriteAsync($"URL:{context.Request.Path + context.Request.QueryString}"); ???????????????}); ???????????app.UseMvc(); ???????}启动该项目,在浏览器地址栏输入 : https://localhost:44303/redirect/123 后,
可以看出,客户端一共请求了两次,浏览器地址栏变成了重定向的URL.
URL重写
URL重写是服务器端操作.重写URL不需要往返服务器,重写的URL也不会返回客户端,也不会出现在浏览器地址栏.
示例:
???????public void Configure(IApplicationBuilder app, IHostingEnvironment env) ???????{ ???????????...other codes ???????????var options = new RewriteOptions(); ???????????options.AddRewrite("^rewrite/(.*)", "api/test", true);//重写URL,false/true 表示如果当前规则适用,是否跳过其他重写规则. ??????????????????????app.UseRewriter(options); ???????????app.Run(async context => ???????????????{ ???????????????????//注意重定向和重写URL两种情况下,浏览器地址栏和页面显示的 URL 的区别. ???????????????????await context.Response.WriteAsync($"URL:{context.Request.Path + context.Request.QueryString}"); ???????????????}); ???????????app.UseMvc(); ???????} ???}在浏览器地址栏输入 : https://localhost:44303/rewrite/1
RewriteOptions 类型提供了一个 Add 方法,接收一个委托.当请求地址符合一个规则后,方法传递的委托便会执行.这里以修改 reContext.Result 的值为例.示例:
???????????{ ???????????????RewriteOptions options = new RewriteOptions(); ???????????????options.AddRewrite("^rewrite*", "test", true).Add(reContext => ???????????????{ ???????????????????reContext.Result = RuleResult.EndResponse; ???????????????}); ???????????????app.UseRewriter(options); ???????????????app.Run(async context => { await context.Response.WriteAsync(context.Request.Path + context.Request.QueryString); }); ???????????}只有请求地址符合规则时才会执行 app.Run(async context => { await context.Response.WriteAsync(context.Request.Path + context.Request.QueryString); }) 这句代码.
测试图如下:
可以看到,上面的请求不符合规则,页面上什么都没显示;
下面的请求符合规则,页面显示出了重写后的请求路径.
上面所有重写的示例中,重写的规则都是写在代码里面的,而ASP.NET Core 还提供了从文件中读取规则的方式.
新建一个文件夹 Rule ,添加一个 IISUrlRewrite.xml 文件,内容如下:
<rewrite> ?<rules> ???<rule name="MyIISUrlRewrite" stopProcessing="true"> ?????<match url="^rewrite/(.*)"/> ?????<!--还 没发现 appendQueryString = false 和 true 的区别--> ??????????<action type="Rewrite" url="api/values/{R:1}" appendQueryString="false"/> ???</rule> ?</rules></rewrite>修改 Configure 方法:
???????public void Configure(IApplicationBuilder app, IHostingEnvironment env) ???????{ ???????????...... ???????????var options = new RewriteOptions(); ???????????//方法一: ???????????//using (StreamReader sr = File.OpenText(Path.Combine(env.ContentRootPath, @"Rule\IISUrlRewrite.xml"))) ???????????//{ ???????????// ???options.AddIISUrlRewrite(sr); ???????????// ???app.UseRewriter(options); ???????????//} ???????????//方法二: ???????????var fileProvider = new PhysicalFileProvider(Path.Combine(env.ContentRootPath, "Rule")); ???????????options.AddIISUrlRewrite(fileProvider, "IISUrlRewrite.xml"); ???????????app.UseRewriter(options); ???????????app.Run(async context => ???????????????{ ???????????????????await context.Response.WriteAsync(context.Request.Path + context.Request.QueryString); ???????????????}); ???????????app.UseMvc(); ???????}图就不上了.
虽然还没用 ASP.NET Core 开发过任何项目,但是我觉得下面这种重写和重定向的方法或许会是用得最多的,因为它足够灵活.
???public class MyRule : IRule ???{ ???????//可以自定义构造函数,做一些验证 ???????//public MyRule(string extension, string newPath) ???????//{ ???????// ???if (string.IsNullOrEmpty(extension)) ???????// ???{ ???????// ???????throw new ArgumentException(nameof(extension)); ???????// ???} ???????// ???if (!Regex.IsMatch(extension, @"^rewrite*")) ???????// ???{ ???????// ???????throw new ArgumentException("Invalid extension", nameof(extension)); ???????// ???} ???????// ???if (!Regex.IsMatch(newPath, @"(/[A-Za-z0-9]+)+?")) ???????// ???{ ???????// ???????throw new ArgumentException("Invalid path", nameof(newPath)); ???????// ???} ???????// ???_extension = extension; ???????// ???_newPath = new PathString(newPath); ???????//} ???????//private readonly string _extension; ???????//private readonly PathString _newPath; ???????private readonly string _extension; ???????private readonly string _newPath; ???????public MyRule(string extension, string newPath) ???????{ ???????????_extension = extension; ???????????_newPath = newPath; ???????} ???????public void ApplyRule(RewriteContext context) ???????{ ???????????HttpRequest request = context.HttpContext.Request; ???????????HttpResponse response = context.HttpContext.Response; ???????????//可以重写 ???????????request.Path = new PathString(_newPath); ???????????context.Result = RuleResult.SkipRemainingRules; ???????????//可以重定向 ???????????//if (request.Path.Value.EndsWith(_extension, StringComparison.OrdinalIgnoreCase)) ???????????//{ ???????????// ???response.StatusCode = StatusCodes.Status302Found; ???????????// ???context.Result = RuleResult.EndResponse; ???????????// ???response.Headers[HeaderNames.Location] = _newPath; ???????????//} ???????} ???} ???????public void Configure(IApplicationBuilder app, IHostingEnvironment env) ???????{ ???????????if (env.IsDevelopment()) ???????????{ ???????????????app.UseDeveloperExceptionPage(); ???????????} ???????????else ???????????{ ???????????????app.UseHsts(); ???????????} ???????????RewriteOptions options = new RewriteOptions(); ???????????options.Add(new MyRule("rewrite","/api/test")); ???????????app.UseRewriter(options); ???????????app.UseHttpsRedirection(); ???????????app.UseMvc(); ???????} ???}ASP.NET Core 2.2 基础知识(四) URL重写中间件
原文地址：https://www.cnblogs.com/lonelyxmas/p/10217733.html