获取缓存文件大小并清理

通常用于删除缓存的时，计算缓存大小

//单个文件的大小

- (long long) fileSizeAtPath:(NSString*) filePath{
    NSFileManager* manager = [NSFileManager defaultManager];
    if ([manager fileExistsAtPath:filePath]){
        return [[manager attributesOfItemAtPath:filePath error:nil] fileSize];
    }
    return 0;
}

//遍历文件夹获得文件夹大小，返回多少M

- (float ) folderSizeAtPath:(NSString*) folderPath{
    NSFileManager* manager = [NSFileManager defaultManager];
    if (![manager fileExistsAtPath:folderPath]) return 0;
    NSEnumerator *childFilesEnumerator = [[manager subpathsAtPath:folderPath] objectEnumerator];
    NSString* fileName;
    long long folderSize = 0;
    while ((fileName = [childFilesEnumerator nextObject]) != nil){
        NSString* fileAbsolutePath = [folderPath stringByAppendingPathComponent:fileName];
        folderSize += [self fileSizeAtPath:fileAbsolutePath];
    }
    return folderSize/(1024.0*1024.0);
}

SDImageCache计算缓存方法

- (NSUInteger)getSize {
    __block NSUInteger size = 0;
    dispatch_queue_t ioQueue = dispatch_queue_create("com.hackemist.SDWebImageCache", DISPATCH_QUEUE_SERIAL);
    dispatch_sync(ioQueue, ^{
        NSDirectoryEnumerator *fileEnumerator = [_fileManager enumeratorAtPath:self.diskCachePath];
        for (NSString *fileName in fileEnumerator) {
            NSString *filePath = [self.diskCachePath stringByAppendingPathComponent:fileName];
            NSDictionary *attrs = [[NSFileManager defaultManager] attributesOfItemAtPath:filePath error:nil];
            size += [attrs fileSize];
        }
    });
    return size;
}

删除缓存

//单文件

-(void)cleanDisk{
    NSFileManager *defaultManager = [NSFileManager defaultManager];
    [defaultManager removeItemAtPath:self.diskCachePath error:nil];
}

多文件

-(void)cleanDisk{
    dispatch_async(
                   dispatch_get_global_queue(DISPATCH_QUEUE_PRIORITY_DEFAULT, 0)
                   , ^{
                       NSString *cachPath = [NSSearchPathForDirectoriesInDomains(NSCachesDirectory,NSUserDomainMask, YES) objectAtIndex:0];

                       NSArray *files     = [[NSFileManager defaultManager] subpathsAtPath:cachPath];
                       NSLog(@"files :%d",[files count]);
                       for (NSString *p in files) {
                           NSError *error;
                       NSString *path     = [cachPath stringByAppendingPathComponent:p];
                           if ([[NSFileManager defaultManager] fileExistsAtPath:path]) {
                               [[NSFileManager defaultManager] removeItemAtPath:path error:&error];
                           }
                       }
    [self performSelectorOnMainThread:@selector(clearCacheSuccess) withObject:nil waitUntilDone:YES];

}

-(void)clearCacheSuccess
{
    NSLog(@"清理成功");
}