OC10_文件练习

//
//  TextHander.h
//  OC10_文件练习
//
//  Created by zhangxueming on 15/6/19.
//  Copyright (c) 2015年 zhangxueming. All rights reserved.
//

#import <Foundation/Foundation.h>

@interface TextHander : NSObject

+ (void)replaceStringInTextFile:(NSString *)path withOldString:(NSString *)dstString toNewString:(NSString *)newString;

+ (void)replaceStringInDirectory:(NSString *)path withOldString:(NSString *)dstString toNewString:(NSString *)newString fileType:(NSString *)type;

@end

//
//  TextHander.m
//  OC10_文件练习
//
//  Created by zhangxueming on 15/6/19.
//  Copyright (c) 2015年 zhangxueming. All rights reserved.
//

#import "TextHander.h"

@implementation TextHander

+ (void)replaceStringInTextFile:(NSString *)path withOldString:(NSString *)dstString toNewString:(NSString *)newString
{
    //备份文件 /name  /name_bak
    NSFileManager *fm = [NSFileManager defaultManager];
    [fm copyItemAtPath:path toPath:[path stringByAppendingString:@"_bak"] error:nil];
    //1.创建文件句柄
    NSFileHandle *fh = [NSFileHandle fileHandleForUpdatingAtPath:path];

    //2.读取文件
    NSData *data = [fh readDataToEndOfFile];
    NSString *dataString = [[NSString alloc] initWithData:data encoding:NSUTF8StringEncoding];
    //3.替换内容
    dataString = [dataString stringByReplacingOccurrencesOfString:dstString withString:newString];
    //4.文件清空
    [fh truncateFileAtOffset:];
    //5.写文件
    [fh writeData:[dataString dataUsingEncoding:NSUTF8StringEncoding]];
    //6.同步文件
    [fh synchronizeFile];
    //7.关闭文件
    [fh closeFile];
}

+ (void)replaceStringInDirectory:(NSString *)path withOldString:(NSString *)dstString toNewString:(NSString *)newString fileType:(NSString *)type
{
    //1.遍历目录
    NSFileManager *fm = [NSFileManager defaultManager];
    NSArray *contents = [fm subpathsOfDirectoryAtPath:path error:nil];
    // /dic/filename.txt
    //2.遍历数组 找到指定类型的文件
    for (NSString *item in contents) {
        NSString *name = [item pathExtension];
        if ([name isEqualToString:type]) {
            [self replaceStringInTextFile:[path stringByAppendingFormat:@"/%@",item] withOldString:dstString toNewString:newString];
        }
    }
}

@end

//
//  main.m
//  OC10_文件练习
//
//  Created by zhangxueming on 15/6/19.
//  Copyright (c) 2015年 zhangxueming. All rights reserved.
//

#import <Foundation/Foundation.h>
#import "TextHander.h"

//把path指定的文件中的字符串 "him" 替换为 "me”

//[LZXTextHandle replaceStringInTextFile:FILE_PATH withOldString:@"him" toNewString:@"me"];
//以下代码的作用:
//把path指定的文件夹中的txt文件中的字符串"him"替换为字符串"me"

//[LZXTextHandle replaceStringInDirectory:DIR_PATH withOldString:@"him" toNewString:@"me" fileType:@"txt"];
int main(int argc, const char * argv[]) {
    @autoreleasepool {
        // insert code here...
        //NSLog(@"Hello, World!");
        //[TextHander replaceStringInTextFile:@"/Users/zhangxueming/Desktop/Test/3.txt" withOldString:@"him" toNewString:@"me"];
        [TextHander replaceStringInDirectory:@"/Users/zhangxueming/Desktop/Test" withOldString:@"him" toNewString:@"me" fileType:@"txt"];

    }
    return ;
}