WebAPI-HTTP编程模型

带着问题去思考，大家好！
它是什么？它包含什么？它能干什么？

消息

http编程模型的核心就是消息抽象，表示为：httprequestmessage,httpresponsemessage.用于客户端和服务端之间交换请求和响应消息。

httpmethod类包含了一组静态属性：

   private static readonly httpmethod getmethod = new httpmethod("get");

        private static readonly httpmethod putmethod = new httpmethod("put");

        private static readonly httpmethod postmethod = new httpmethod("post");

        private static readonly httpmethod deletemethod = new httpmethod("delete");

        private static readonly httpmethod headmethod = new httpmethod("head");

        private static readonly httpmethod optionsmethod = new httpmethod("options");

        private static readonly httpmethod tracemethod = new httpmethod("trace")

标头

• httprequestheaders：包含请求标头
• httpresponseheaders：包含响应标头
• httpcontentheaders：包含内容标头

 

消息内容

httpcontent包含了非虚拟公共方法

• task<string> readasstringasync()
• task<byte[]> readasbytearrayasync()
• task<stream> readasstreamasync()
• task copytoasync(stream stream, transportcontext context)

第一种方式用于推送方式访问原始的消息内容。将一个流传递给copyasync方法，然后把消息内容推送到这个流中

using(car client=new htppclient())
{
    var response=
          await client.getasync("",httpcompletionoption.responseheadersread);
response.ensuresuccessstatuscode();
var ms=new memorysteam();
await response.content.copytoasync(ms);
assert.true(ms.length>0);
}

也可以使用readasstreamasync().拉取方式访问。这个方法异步返回一个流

            using(var client=new httpclient())
            {
                var response = await client.getasync("");
                response.ensuresuccessstatuscode();
                var steam = await response.content.readasstreamasync();
                var buffer = new byte[2 * 1024];
                var len = await steam.readasync(buffer, 0, buffer.length);
               
            }

readasstringasync和readasbytearrayasync-异步提供消息内容的缓冲副本。readasstringasync返回原始的字节内容，readasbytearrayasync将内容解码为字符串返回

当然也可以扩展为

public override task<object> readcontentasync(httprequestmessage request, ienumerable<mediatypeformatter> formatters, iformatterlogger formatterlogger)