OC 日常笔记碎片知识
前言:几乎每个应用都有清除缓存的功能,因此为了代码复用性,考虑封装功能.
- 1-实现思路大概分析:
1.先点击didSelectRow,打印文件夹主路径.在里随便生成一个文件,例如”mp3”.
2.先获取文件路径.
3.通过遍历拼接文件.
4.模仿SDWebImage累加文件,计算文件总大小.
- 2-代码演示(已经封装好的代码,只需给路径,点语法调用就可以计算文件)
给字符串做分类
#import <Foundation/Foundation.h>
@interface NSString (JYhExtenation)
- (unsigned long long)fileSize;
@end
#import "NSString+JYhExtenation.h"
@implementation NSString (JYhExtenation)
- (unsigned long long)fileSize
{
//初始化总大小
unsigned long long size = 0;
//文件管理者
NSFileManager *mgr = [NSFileManager defaultManager];
//是否为文件夹
BOOL isDirectory = NO;
//路径是否存在
BOOL exists = [mgr fileExistsAtPath:self isDirectory:&isDirectory];
if (!exists) return size;
//如是文件夹isDirectory会返回YES
if (isDirectory) //文件夹
{
//通过遍历获得文件的总大小
NSDirectoryEnumerator *enumerator = [mgr enumeratorAtPath:self];
for (NSString *subpatchStr in enumerator)
{
//第一步:拼接dirpath文件夹与里面的文件(本质是字符串)
NSString *fullSubpath = [self stringByAppendingPathComponent:subpatchStr];
//第二步:获取文件的属性
size += [mgr attributesOfItemAtPath:fullSubpath error:nil].fileSize;
}
}else // 文件
{
size = [mgr attributesOfItemAtPath:self error:nil].fileSize;
}
return size;
}
@end
快速计算文件夹尺寸.gif
*会发现有一点偏差. 原因是本身文件夹不是计算范围, 文件夹属于轻量级,只需清除文件夹里的文件即可.
自定义cell把功能封装在里面
- 3-代码演示:
#import <UIKit/UIKit.h>
@interface JYhClearCacheCell : UITableViewCell
@end
#import "JYhClearCacheCell.h"
//获取caches文件夹
#define JYhCustomPath [NSSearchPathForDirectoriesInDomains(NSCachesDirectory, NSUserDomainMask, YES).lastObject stringByAppendingPathComponent:@"custom"]
--------------------------------------------------------
@implementation JYhClearCacheCell
//初始化样式方法
- (instancetype)initWithStyle:(UITableViewCellStyle)style reuseIdentifier:(NSString *)reuseIdentifier
{
if (self = [super initWithStyle:style reuseIdentifier:reuseIdentifier]) {
//创建菊花view
UIActivityIndicatorView *loadingView = [[UIActivityIndicatorView alloc]initWithActivityIndicatorStyle:UIActivityIndicatorViewStyleGray];
//开启动画
[loadingView startAnimating];
//赋值
self.accessoryView = loadingView;
self.textLabel.text = @"清空缓存(努力计算大小...)";
//在子线程计算缓存大小
dispatch_async(dispatch_get_global_queue(0, 0), ^{
//获得缓存文件夹路径
// unsigned long long size = [NSSearchPathForDirectoriesInDomains(NSCachesDirectory, NSUserDomainMask, YES).lastObject stringByAppendingPathComponent:@"custom"].fileSize;
//计算文件大小
unsigned long long size = JYhCustomPath.fileSize;
// JYHLog(@"%@",JYhCustomPath);
size += [SDImageCache sharedImageCache].getSize;
//转换文件size
NSString *sizeText = @"0";
if (size >= 1000 * 1000 * 1000) // size >= 1GB
{
sizeText = [NSString stringWithFormat:@"%.1fGB",size / 1000.0 / 1000.0 / 1000.0];
}else if (size >= 1000 * 1000) // 1GB > size >= 1MB
{
sizeText = [NSString stringWithFormat:@"%.1fMB",size / 1000.0 / 1000.0 ];
}else if (size >= 1000) //1MB > size >= 1KB
{
sizeText = [NSString stringWithFormat:@"%zdB",size];
}
//生成文字
NSString *cellStr = [NSString stringWithFormat:@"清除缓存(%@)",sizeText];
//回到主线程设置文字
dispatch_async(dispatch_get_main_queue(), ^{
//设置textLabel
self.textLabel.text = cellStr;
//清空控件
self.accessoryView = nil;
//设置系统箭头样式
self.accessoryType = UITableViewCellAccessoryDisclosureIndicator;
});
});
UITapGestureRecognizer *tap = [[UITapGestureRecognizer alloc]initWithTarget:self action:@selector(tapClear:)];
[self addGestureRecognizer:tap];
}
return self;
}
--------------------------------------------------------
//点击手势方法
- (void)tapClear:(UITapGestureRecognizer *)tap
{ //设置指示器的样式
[SVProgressHUD setDefaultMaskType:SVProgressHUDMaskTypeBlack];
//弹出指示器
[SVProgressHUD showWithStatus:@"正在清除缓存..."];
//延迟执行模仿网络繁忙
dispatch_after(dispatch_time(DISPATCH_TIME_NOW, (int64_t)(2.0 * NSEC_PER_SEC)), dispatch_get_main_queue(), ^{
//删除缓存文件
[[SDImageCache sharedImageCache] clearDiskOnCompletion:^{
//开子线程清除缓存
dispatch_async(dispatch_get_global_queue(0, 0), ^{
//获取文件管理者
NSFileManager *mgr = [NSFileManager defaultManager];
//确定路径
[mgr removeItemAtPath:JYhCustomPath error:nil];
//创建一个新的文件夹
[mgr createDirectoryAtPath:JYhCustomPath withIntermediateDirectories:YES attributes:nil error:nil];
//所有缓存都清除完毕
dispatch_async(dispatch_get_main_queue(), ^{
//隐藏指示器
[SVProgressHUD dismiss];
//设置文字
self.textLabel.text = @"清除缓存(0B)";
});
});
}];
});
}
@end
unsigned long long//8个字节，64位的无符号长整形.
unsigned long//4个字节的无符号长整形.
unsigned 变量名 ；是无符号整形.
清除缓存.gif
