iOS经典讲解之清除缓存文件

 

转载请标明出处：http://blog.csdn.net/loving_ios/article/details/49251321

清除缓存之前先要计算文件的大小：

 

// 计算目录大小
- (CGFloat)folderSizeAtPath:(NSString *)path
{
// 利用NSFileManager实现对文件的管理</span>

 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];
        }
    }
}

 

计算沙盒中文件的大小并删除沙盒中文件的例子：

 

- (void)cleanCaches
{
    [self cleanCaches:NSSearchPathForDirectoriesInDomains(NSDocumentDirectory, NSUserDomainMask, YES).firstObject];
    [self cleanCaches:NSSearchPathForDirectoriesInDomains(NSLibraryDirectory, NSUserDomainMask, YES).firstObject];
    [self cleanCaches:NSTemporaryDirectory()];
}

// 清除缓存

            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];