.net core web api 获取request body的纯文本

本文代码

https://github.com/wuhaibo/readPlainTextDotNetCoreWepApi

总有些时候我们希望获得Request body 的纯文本 那么怎么做呢？很简单。如下所示

        public string GetJsonString([FromBody]string content)
        {
            return "content: " + content ;
        }

测试结果如下

request：
POST http://localhost:5000/api/values/GetJsonString HTTP/1.1
Accept-Encoding: gzip,deflate
Content-Type: application/json
Content-Length:
Host: localhost:
Connection: Keep-Alive
User-Agent: Apache-HttpClient/4.1. (java 1.5)
"test"

response：
HTTP/1.1  OK
Date: Wed,  Mar  :: GMT
Content-Type: text/plain; charset=utf-
Server: Kestrel
Transfer-Encoding: chunked

content: test 

可以看到content被赋值test。 但有个问题request body的内容必须是合法的json而且request 的media type也得是json

举个例子，

request：
POST http://localhost:5000/api/values/GetJsonString HTTP/1.1
Accept-Encoding: gzip,deflate
Content-Type: application/xml
Content-Length:
Host: localhost:
Connection: Keep-Alive
User-Agent: Apache-HttpClient/4.1. (java 1.5)
test

response：
HTTP/1.1  OK
Date: Wed,  Mar  :: GMT
Content-Type: text/plain; charset=utf-
Server: Kestrel
Transfer-Encoding: chunked

content:  

可以看到由于request body的内容 test 并不是个合法的xml，所以我们返回的content是空。

有个更好的方法 如下所示，这种方法不论是media type都可以获得request body 的纯文本

        public string GetJsonString3(string content)
        {
            var reader = new StreamReader(Request.Body);
            var contentFromBody = reader.ReadToEnd();
            return "content: " + content
                   + " contentFromBody: " + contentFromBody;
        }

测试结果

request：
POST http://localhost:5000/api/values/GetJsonString3 HTTP/1.1
Accept-Encoding: gzip,deflate
Content-Type: application/xml
Content-Length:
Host: localhost:
Connection: Keep-Alive
User-Agent: Apache-HttpClient/4.1. (java 1.5)
test

response：
HTTP/1.1  OK
Date: Wed,  Mar  :: GMT
Content-Type: text/plain; charset=utf-
Server: Kestrel
Transfer-Encoding: chunked

content:  contentFromBody: test 

可以看到contentFromBody中我们得到了request body的内容。 注意参数没有[FromBody]这个属性 如果加了这个属性，那么如果request body内容匹配request的media type那么Request.body的position会被置于结尾的位置。 举个例子

        public string GetJsonString2([FromBody]string content)
        {

            var reader = new StreamReader(Request.Body);
            var contentFromBody = reader.ReadToEnd();

            Request.Body.Position = ;

            var reader2 = new StreamReader(Request.Body);
            var contentFromBody2 = reader2.ReadToEnd();

            return "content: " + content
                   + " contentFromBody: " + contentFromBody
                   + " contentFromBody2: " + contentFromBody2;
        }

测试结果

request:
POST http://localhost:5000/api/values/GetJsonString2 HTTP/1.1
Accept-Encoding: gzip,deflate
Content-Type: application/json
Content-Length:
Host: localhost:
Connection: Keep-Alive
User-Agent: Apache-HttpClient/4.1. (java 1.5)
test

response:
HTTP/1.1  OK
Date: Wed,  Mar  :: GMT
Content-Type: text/plain; charset=utf-
Server: Kestrel
Transfer-Encoding: chunked

content:  contentFromBody:  contentFromBody2: test