objectc中NSFileManger 和NSFileHandler的用法

 

//
//  main.m
//  FileManager
//
//  Created by ganchaobo on 13-5-4.
//  Copyright (c) 2013年 ganchaobo. All rights reserved.
//

#import <Foundation/Foundation.h>

void copyfile (){
    //NSFileManager对文件进行（复制 创建，删除）等操作 NSFilehandler是对文件内容进行操作
    
    NSFileManager *fileManager=[NSFileManager defaultManager];
    
    //  NSData *date=[NSData dataWithContentsOfFile:@"/Users/ganchaobo/Desktop/1.txt"];
    
    //创建文件，
    BOOL isCreate=[fileManager createFileAtPath:@"/Users/ganchaobo/Desktop/a.txt" contents:nil attributes:nil];
    if(isCreate){
        NSLog(@"create success");
    }
    else{
        NSLog(@"create faied");
    }
    NSFileHandle *inFileHandle=[NSFileHandle fileHandleForReadingAtPath:@"/Users/ganchaobo/Desktop/1.txt"];
    
    //读取文件内容第一种de写法
    // NSData  *readData= [inFileHandle availableData];
    //读取文件内容的第二种写法
    NSData  *readData=  [inFileHandle readDataToEndOfFile];//read file data
    NSFileHandle *outFileHandle=[NSFileHandle fileHandleForWritingAtPath:@"/Users/ganchaobo/Desktop/a.txt"];
    [outFileHandle writeData:readData];
    
    [inFileHandle closeFile];
    [outFileHandle closeFile];
}
void Appendstringfile(){
    NSFileHandle *filehandle=[NSFileHandle fileHandleForUpdatingAtPath:@"/Users/ganchaobo/Desktop/1.txt"];

    
    //设置流的节点最后
    //[filehandle seekToEndOfFile];
    //设置流的节点到文件的一半位置
   NSUInteger length= [[filehandle readDataToEndOfFile] length]/2;
    [filehandle seekToFileOffset:length];

     //NSStringEncoding code= CFStringConvertEncodingToNSStringEncoding(kCFStringEncodingGB_18030_2000);
          
    NSString *str=@"我要追加数据";
    NSData *date= [str dataUsingEncoding:NSUTF8StringEncoding];
    [filehandle writeData:date];
    
    [filehandle closeFile];
    
}

int main(int argc, const char * argv[])
{

    @autoreleasepool {
        
   
        Appendstringfile();

    }
    return 0;
}