iOS计算本地缓存文件大小（M）

- (float)getCacheFileSize
{
    NSFileManager *fileManager = [NSFileManager defaultManager];
    double fileSize = 0.0;
    NSString *cachPath = [NSSearchPathForDirectoriesInDomains(NSCachesDirectory, NSUserDomainMask, YES) objectAtIndex:0];
    NSArray *files = [fileManager subpathsAtPath:cachPath];
    for (NSString *fileName in files)
    {
        NSString *path = [cachPath stringByAppendingPathComponent:fileName];
        if ([fileManager fileExistsAtPath:path])
        {
            NSDictionary *fileAttributes = [fileManager attributesOfItemAtPath:path error:nil];
            fileSize += (double)([fileAttributes fileSize]);
        }
    }
    return fileSize/( 1024.0 * 1024.0);
}