问题
I'm trying to find a file size.
NSFileHandle *output = [NSFileHandle fileHandleForWritingAtPath:self.finalPath];
//seek to begin of the file
[output seekToFileOffset:0];
NSData *mydata = [output availableData];
NSLog(@"length: %d", [mydata length]);
But my length is equl to zero. Why?
回答1:
availableData
is for reading files. If you just want to find out the size of a file, you don't actually have to open it. Just use NSFileManager
like this:
NSDictionary *attributes = [[NSFileManager defaultManager] attributesOfItemAtPath:self.finalPath error:NULL];
unsigned long long fileSize = [attributes fileSize]; // in bytes
回答2:
[fileHandler seekToEndOfFile], this returns the length of your file data, your code [output seekToFileOffset:0] means from 0-0,so there is no data
来源:https://stackoverflow.com/questions/9479824/im-trying-to-find-a-file-size-but-my-length-is-equl-to-zero