ASIHTTPRequest 网络发送数据为空

在项目用模拟器发现服务器收到客户端的内容为空。经过调试发现需要增加以下代码：

request = [[ASIHTTPRequest
requestWithURL:[NSURL
URLWithString:t_URL]] retain];
[request
setDelegate:self];
[request
appendPostData:[t_Register
dataUsingEncoding:NSUTF8StringEncoding
allowLossyConversion:YES]];
[request
setRequestMethod:@"POST"];
[request
addRequestHeader:@"Content-Type"
value:@"application/json"];
[request
setShouldAttemptPersistentConnection:NO];
[request
setDidFinishSelector:@selector(requestDone:)];
[request
setDidFailSelector:@selector(requestWentWrong:)];
[request
startAsynchronous];