c# - ASP.NET OWIN 中间件 - 修改 HTTP 响应

Question

我需要拦截所有aspx和js文件请求，并替换一些文本标签存在。这个中间件应该作为 IIS 模块工作，显然不会干扰 Web 应用程序的正常流程。我写了一些代码，但我不知道该怎么做。

public partial class Startup
{
    public void Configuration(IAppBuilder app)
    {
        app.Use(typeof(FilterMiddleware), Console.Out);
    }
}

public class FilterMiddleware : OwinMiddleware
{
    private readonly TextWriter logger;
    private readonly OwinMiddleware nextMiddleware;

    public FilterMiddleware(OwinMiddleware nextMiddleware, TextWriter logger) : base(nextMiddleware)
    {
        this.nextMiddleware = nextMiddleware;
        this.logger = logger;
    }

    public override async Task Invoke(IOwinContext context)
    {
        var headers = context.Request.Headers;

        // IF .js OR .ASPX REPLACE TEXT HERE //

        await nextMiddleware.Invoke(context);
    }
}

Answer 1

我想你要找的是

if (context.Request.ContentType = "application/json") // or whatever MIME type
{
   ...
}

然后在完成所有处理后，不要忘记创建回复

context.Response.ContentType = "application/json";
string result = ""; // whatever string you are sending back
await context.Response.WriteAsync(result);

但是，如果遇到某种错误，例如不受支持的方法(即 PUT)

context.Response.StatusCode = StatusCodes.Status405MethodNotAllowed;
await context.Response.WriteAsync(String.Empty);