delphi idhttp 如何自定义http消息头？
比如我想发送这个“消息头”，如果不用idhttp1.Request这个属性，改如何写呢？
如果用idhttp1.Request这样写，那“Expect: 100-continue”这个又如何写呢？

POST /app/login HTTP/1.1
Accept-Language: zh-CN
Accept: */*
User-Agent: Mozilla/4.0 (compatible; MSIE 6.0; Windows NT 5.2; SV1; .NET CLR 1.1.4322; .NET CLR 2.0.50727)
Content-Type: application/x-www-form-urlencoded
Host: www.docin.com
Content-Length: 52
Expect: 100-continue
Connection: Close

[解决办法]
indy 10 用
IdHTTP1.Request.CustomHeaders.Values['expect'] := '100-continu';