iOS获取剩余存储空间

//ios获取剩余存储空间
-(void)usedSpaceAndfreeSpace{
    NSString* path = [NSSearchPathForDirectoriesInDomains(NSDocumentDirectory, NSUserDomainMask, YES)objectAtIndex:] ;
    NSFileManager* fileManager = [[NSFileManager alloc ]init];
    NSDictionary *fileSysAttributes = [fileManager attributesOfFileSystemForPath:path error:nil];
    NSNumber *freeSpace = [fileSysAttributes objectForKey:NSFileSystemFreeSize];
    NSNumber *totalSpace = [fileSysAttributes objectForKey:NSFileSystemSize];
    NSString  * str= [NSString stringWithFormat:@"已占用%0.1fG/剩余%0.1fG",([totalSpace longLongValue] - [freeSpace longLongValue])/1024.0/1024.0/1024.0,[freeSpace longLongValue]/1024.0/1024.0/1024.0];
    NSLog(@"--------%@",str);
}