iOS清除缓存（OC实现）

//清除缓存按钮的点击事件
- (void)putBufferBtnClicked:(UIButton *)btn{
CGFloat size = [self folderSizeAtPath:NSSearchPathForDirectoriesInDomains(NSDocumentDirectory, NSUserDomainMask, YES).lastObject] + [self folderSizeAtPath:NSSearchPathForDirectoriesInDomains(NSLibraryDirectory, NSUserDomainMask, YES).lastObject] + [self folderSizeAtPath:NSTemporaryDirectory()];

NSString *message = size > 1 ? [NSString stringWithFormat:@"缓存%.2fM, 删除缓存", size] : [NSString stringWithFormat:@"缓存%.2fK, 删除缓存", size * 1024.0];

UIAlertController *alert = [UIAlertController alertControllerWithTitle:nil message:message preferredStyle:(UIAlertControllerStyleAlert)];

UIAlertAction *action = [UIAlertAction actionWithTitle:@"确定" style:(UIAlertActionStyleDefault) handler:^(UIAlertAction *action) {                [self cleanCaches];            }];

UIAlertAction *cancel = [UIAlertAction actionWithTitle:@"取消" style:(UIAlertActionStyleCancel) handler:nil];
[alert addAction:action];
[alert addAction:cancel];
[self showDetailViewController:alert sender:nil];
}

// 计算目录大小
- (CGFloat)folderSizeAtPath:(NSString *)path{
// 利用NSFileManager实现对文件的管理
NSFileManager *manager = [NSFileManager defaultManager];
CGFloat size = 0;
if ([manager fileExistsAtPath:path]) {
// 获取该目录下的文件，计算其大小
NSArray *childrenFile = [manager subpathsAtPath:path];
for (NSString *fileName in childrenFile) {
NSString *absolutePath = [path stringByAppendingPathComponent:fileName];
size += [manager attributesOfItemAtPath:absolutePath error:nil].fileSize;
}
// 将大小转化为M
return size / 1024.0 / 1024.0;
}
return 0;
}
// 根据路径删除文件
- (void)cleanCaches:(NSString *)path{
// 利用NSFileManager实现对文件的管理
NSFileManager *fileManager = [NSFileManager defaultManager];
if ([fileManager fileExistsAtPath:path]) {
// 获取该路径下面的文件名
NSArray *childrenFiles = [fileManager subpathsAtPath:path];
for (NSString *fileName in childrenFiles) {
// 拼接路径
NSString *absolutePath = [path stringByAppendingPathComponent:fileName];
// 将文件删除
[fileManager removeItemAtPath:absolutePath error:nil];
}
}