iOS 自定義讀寫文件

LSCacheFile.h

//
//  LSCacheFile.h
//  iPhone
//
//  Created by xujinzhong on 14-6-5.
//  Copyright (c) 2014年 xujinzhong. All rights reserved.
//

#import <Foundation/Foundation.h>
#import "LSCommonMacro.h"
@interface LSCacheFile : NSObject

//寫入文件
+ (BOOL)writeFileName:(NSString *)fileName data:(id)result;
//讀出文件
+ (id)readFileName:(NSString *)fileName;
//計算文件大小
+ (NSString *)folderSizeStringAtPath:(NSString *)folderPath;
//格式化size為M，K模式
+(NSString*)sizeStringFromSizeLong:(long long) folderSize;
//以B方式獲取目錄下的文件大小
+ (long long)folderSizeAtPath:(NSString*)folderPath;
//判斷文件是否存在
+ (BOOL)isExistsFile:(NSString *)filepath;
//刪除緩存文件
+ (void)deleteCacheFile:(NSString *)filepath;

@end

LSCacheFile.m

//
//  LSCacheFile.m
//  iPhone
//
//  Created by xujinzhong on 14-6-5.
//  Copyright (c) 2014年 xujinzhong. All rights reserved.
//

#import "LSCacheFile.h"
#include "sys/stat.h"


#define PATH_AT_LIBDIR(name) [[NSSearchPathForDirectoriesInDomains(NSLibraryDirectory, NSUserDomainMask, YES) lastObject] stringByAppendingPathComponent:name]

@implementation LSCacheFile

+ (NSString *)filePath:(NSString *)fileName{
    NSString *floderPath = PATH_AT_LIBDIR(@"Caches/LSCacheFinder");
    if(![[NSFileManager defaultManager] fileExistsAtPath:floderPath isDirectory:nil]){
        [[NSFileManager defaultManager] createDirectoryAtPath:floderPath withIntermediateDirectories:NO attributes:nil error:nil];
    }
    return [floderPath stringByAppendingPathComponent:fileName];
}

+ (BOOL)writeFile:(NSString *)fileName object:(id)object{
    if(fileName == nil){
        
        return NO;
    }
    if(![NSKeyedArchiver archiveRootObject:object toFile:fileName]){
        
        return NO;
    }
    return YES;
}

+ (id)readFile:(NSString *)fileName{
    if(fileName == nil){
        return nil;
    }
    return [NSKeyedUnarchiver unarchiveObjectWithFile:fileName];
}

+ (BOOL)writeFileName:(NSString *)fileName data:(id)result{
   NSString *pathName =  [LSCacheFile filePath:fileName];
    if ([LSCacheFile isExistsFile:pathName]) {
        [[NSFileManager defaultManager] removeItemAtPath:pathName error:nil];
    }
    return [LSCacheFile writeFile:pathName object:result];
}

+ (id)readFileName:(NSString *)fileName{
    if (!fileName) {
        return nil;
    }
    if(![LSCacheFile isExistsFile:fileName]){
        return nil;
    }

    id object = [LSCacheFile readFile:[LSCacheFile filePath:fileName]];
    if (!object) {
        return nil;
    }
    return object;
}

+ (BOOL)isExistsFile:(NSString *)filepath{
    NSFileManager *filemanage = [NSFileManager defaultManager];
    return [filemanage fileExistsAtPath:[LSCacheFile filePath:filepath]];
}

+(void)deleteCacheFile:(NSString *)filepath
{
    BOOL flag = NO;
    if([[NSFileManager defaultManager] fileExistsAtPath:filepath isDirectory:&flag])
    {
        [[NSFileManager defaultManager] removeItemAtPath:filepath error:nil];
    }
}

//計算文件夾下文件的總大小
+ (NSString *)folderSizeStringAtPath:(NSString *)folderPath
{
    long long folderSize = [LSCacheFile folderSizeAtPath:folderPath];
    return [self sizeStringFromSizeLong:folderSize];
}

+(NSString*)sizeStringFromSizeLong:(long long) folderSize
{
    if (folderSize < 1024) {
        return @"0K";
    }else if(folderSize/1024.0 < 1024){
        return [NSString stringWithFormat:@"%.2fK",folderSize/1024.0];
    }else if(folderSize/1024.0/1024.0 < 1024){
        return [NSString stringWithFormat:@"%.2fM",folderSize/1024.0/1024.0];
    }else if(folderSize/1024.0/1024.0/1024.0 < 1024){
        return [NSString stringWithFormat:@"%.2fG",folderSize/1024.0/1024.0/1024.0];
    }
    return @"";
}

+ (long long)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 += [LSCacheFile fileSizeAtPath:fileAbsolutePath];
    }
    return folderSize;
}

+ (long long)fileSizeAtPath:(NSString*)filePath{
    struct stat st;
    if(lstat([filePath cStringUsingEncoding:NSUTF8StringEncoding], &st) == 0){
        return st.st_size;
    }
    return 0;
}

@end