在URL处获取文件大小Objective-C

Question

我正在寻找一种方法来获取NSURL地址处特定文件的文件大小。这是我已经尝试过，但它始终在日志输出中返回'0'：

NSString *url = @"http://www.examplesite.com/file01.zip"; 

unsigned long long fileSize1 = [[[NSFileManager defaultManager] attributesOfItemAtPath:[url lastPathComponent] error:nil] fileSize]; 
NSLog(@"size of %@ in bytes === %llu", [url lastPathComponent], fileSize1); 

Answer 1

搜索一些后，我发现此解决方案。它在服务器上查找文件的文件大小，并在日志中显示结果。

NSString *url = @"http://www.examplesite.com/file01.zip"; 
       NSURL *URL = [NSURL URLWithString:url]; 
       NSMutableURLRequest *request = [NSMutableURLRequest requestWithURL:URL]; 
       [request setHTTPMethod:@"HEAD"]; 
       NSHTTPURLResponse *response; 
       [NSURLConnection sendSynchronousRequest:request returningResponse:&response error: nil]; 
       long long size = [response expectedContentLength]; 
       NSLog(@"File size before download: %lld",size);