在 HTTP Post 中实现超时

Question

在 HTTP post 连接中实现连接超时（比如 20 秒）的最佳方式是什么？

我目前的代码如下：

-(NSData*) postData: (NSString*) strData
{    
    //postString is the STRING TO BE POSTED
    NSString *postString;

    //this is the string to send
    postString = @"data=";
    postString = [postString stringByAppendingString:strData]; 

    NSURL *url = [NSURL URLWithString:@"MYSERVERHERE"];
    NSMutableURLRequest *request = [NSMutableURLRequest requestWithURL:url];
    NSString *msgLength = [NSString stringWithFormat:@"%d", [postString length]];

    //setting prarameters of the POST connection
    [request setHTTPMethod:@"POST"];
    [request addValue:@"application/x-www-form-urlencoded" forHTTPHeaderField:@"Content-Type"];
    [request addValue:msgLength forHTTPHeaderField:@"Content-Length"];
    [request addValue:@"en-US" forHTTPHeaderField:@"Content-Language"];
    [request setHTTPBody:[postString dataUsingEncoding:NSUTF8StringEncoding]];
    [request setTimeoutInterval:10.0];

    NSLog(@"%@",postString);

    NSURLResponse *response;
    NSError *error;

    NSLog(@"Starting the send!");
    //this sends the information away. everybody wave!
    NSData *urlData = [NSURLConnection sendSynchronousRequest:request returningResponse:&response error:&error];
    NSLog(@"Just finished receiving!");
    if (&error) //OR TIMEOUT
    {
        NSLog(@"ERROR!");
        NSString *errorString = [NSString stringWithFormat:@"ERROR"];
        urlData = [errorString dataUsingEncoding:NSUTF8StringEncoding];
    }
    return urlData;
}

显然超时间隔设置为 10.0，但是当这 10 秒到来时似乎什么都没有发生。

Answer 1

见：

NSMutableURLRequest timeout interval not taken into consideration for POST requests

显然低于 240 秒的超时将被忽略。该问题中投票最高的答案链接到解决方案。但是，我只是推荐使用 ASIHTTPRequest 库。

http://allseeing-i.com/ASIHTTPRequest/