ios---清除缓存

+ (void)removeDirectoryPath:(NSString *)directoryPath
{
    // 获取文件管理者
    NSFileManager *mgr = [NSFileManager defaultManager];
    
    BOOL isDirectory;
    BOOL isExist = [mgr fileExistsAtPath:directoryPath isDirectory:&isDirectory];
    
    if (!isExist || !isDirectory) {
        // 抛异常
        // name:异常名称
        // reason:报错原因
        NSException *excp = [NSException exceptionWithName:@"pathError" reason:@"笨蛋 需要传入的是文件夹路径,并且路径要存在" userInfo:nil];
        [excp raise];
        
    }
    
    // 获取cache文件夹下所有文件,不包括子路径的子路径
    NSArray *subPaths = [mgr contentsOfDirectoryAtPath:directoryPath error:nil];
    
    for (NSString *subPath in subPaths) {
        // 拼接完成全路径
        NSString *filePath = [directoryPath stringByAppendingPathComponent:subPath];
        
        // 删除路径
        [mgr removeItemAtPath:filePath error:nil];
    }

}

// 自己去计算SDWebImage做的缓存
+ (void)getFileSize:(NSString *)directoryPath completion:(void(^)(NSInteger))completion
{
    
    // 获取文件管理者
    NSFileManager *mgr = [NSFileManager defaultManager];
    BOOL isDirectory;
    BOOL isExist = [mgr fileExistsAtPath:directoryPath isDirectory:&isDirectory];
    
    if (!isExist || !isDirectory) {
        // 抛异常
        // name:异常名称
        // reason:报错原因
       NSException *excp = [NSException exceptionWithName:@"pathError" reason:@"笨蛋 需要传入的是文件夹路径,并且路径要存在" userInfo:nil];
        [excp raise];
        
    }
    
    dispatch_async(dispatch_get_global_queue(0, 0), ^{
        
        // 获取文件夹下所有的子路径,包含子路径的子路径
        NSArray *subPaths = [mgr subpathsAtPath:directoryPath];
        
        NSInteger totalSize = 0;
        
        for (NSString *subPath in subPaths) {
            // 获取文件全路径
            NSString *filePath = [directoryPath stringByAppendingPathComponent:subPath];
            
            // 判断隐藏文件
            if ([filePath containsString:@".DS"]) continue;
            
            // 判断是否文件夹
            BOOL isDirectory;
            // 判断文件是否存在,并且判断是否是文件夹
            BOOL isExist = [mgr fileExistsAtPath:filePath isDirectory:&isDirectory];
            if (!isExist || isDirectory) continue;
            
            // 获取文件属性
            // attributesOfItemAtPath:只能获取文件尺寸,获取文件夹不对,
            NSDictionary *attr = [mgr attributesOfItemAtPath:filePath error:nil];
            
            // 获取文件尺寸
            NSInteger fileSize = [attr fileSize];
            
            totalSize += fileSize;
        }
        
        // 计算完成回调
        dispatch_sync(dispatch_get_main_queue(), ^{
            if (completion) {
                completion(totalSize);
            }
        });
        
        

    });   
}

- (NSString *)sizeStr
{
    NSInteger totalSize = _totalSize;
    NSString *sizeStr = @"清除缓存";
    // MB KB B
    if (totalSize > 1000 * 1000) {
        // MB
        CGFloat sizeF = totalSize / 1000.0 / 1000.0;
        sizeStr = [NSString stringWithFormat:@"%@(%.1fMB)",sizeStr,sizeF];
    } else if (totalSize > 1000) {
        // KB
        CGFloat sizeF = totalSize / 1000.0;
        sizeStr = [NSString stringWithFormat:@"%@(%.1fKB)",sizeStr,sizeF];
    } else if (totalSize > 0) {
        // B
        sizeStr = [NSString stringWithFormat:@"%@(%.ldB)",sizeStr,totalSize];
    }

    return sizeStr;
}