查找URL的下载大小(Content-Length)

Question

我正在寻找一些Objective-c代码来查询URL并给出下载大小,类似于这个例子:在下载之前检查下载大小

但是在objective-c中,使用ASIHttp就可以了.

Answer 1

启动HTTP HEAD请求:

NSURL *url = [NSURL URLWithString:@"http://www.google.com/"];
NSMutableURLRequest *httpRequest = [NSMutableURLRequest requestWithURL:url cachePolicy:NSURLRequestUseProtocolCachePolicy timeoutInterval:10];
[httpRequest setHTTPMethod:@"HEAD"];
NSURLConnection *urlConnection = [[NSURLConnection alloc] initWithRequest:httpRequest delegate:self];

实现委托:

- (void)connection:(NSURLConnection *)connection didReceiveResponse:(NSURLResponse *)aResponse {
   long long filesize = [aResponse expectedContentLength];
}