1.http协议组成：
报文首部：状态行（请求行） 请求首部字段 通用字段 其他信息
空行
报文主体
GET请求头： GET /test.php?a=1 HTTP/1.1 Host: localhost Connection: keep-alive Cache-Control: max-age=0 Upgrade-Insecure-Requests: 1 User-Agent: Mozilla/5.0 (Windows NT 10.0; WOW64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/54.0.2840.99 Safari/537.36 Accept: text/html,application/xhtml+xml,application/xml;q=0.9,image/webp,*/*;q=0.8 Accept-Encoding: gzip, deflate, sdch, br Accept-Language: zh-CN,zh;q=0.8
POST请求头： POST /test.php HTTP/1.1 Host: localhost Connection: keep-alive Content-Length: 42 Cache-Control: max-age=0 Origin: http://localhost Upgrade-Insecure-Requests: 1 User-Agent: Mozilla/5.0 (Windows NT 10.0; WOW64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/54.0.2840.99 Safari/537.36 Content-Type: application/x-www-form-urlencoded Accept: text/html,application/xhtml+xml,application/xml;q=0.9,image/webp,*/*;q=0.8 Referer: http://localhost/test.php Accept-Encoding: gzip, deflate, br Accept-Language: zh-CN,zh;q=0.8
2.在命令行下用telnet模拟发送get或post请求
GET请求头： GET /test.php?a=1 HTTP/1.1 HOST:localhost POST请求头： POST /test.php HTTP/1.1 HOST:localhost Content-Length:7 // 必须加上这个头 Content-type:application/x-www-form-urlencoded name=ht // 在上面的请求头黏贴完毕后，回车两次，再输入
// get请求头黏贴后，回车两次，显示请求内容；post请求头，黏贴完毕后，回车，输入post请求参数字符串，自动显示请求内容
原文：http://www.cnblogs.com/taotaoxixihaha/p/6351382.html