OC之文件管理写入文件

////  WriteDate.m//  NSFIleHandleTask1////  Created by New-World on 13-11-3.//  Copyright (c) 2013年 Gary. All rights reserved.//#import "WriteDate.h"@implementation WriteDate-(void)runWrite{    NSFileManager *fileManger=[NSFileManager defaultManager];    NSString *path=NSHomeDirectory();    NSString *filepath=[path stringByAppendingPathComponent:@"Date.text"];//文件路径    BOOL success =[fileManger createFileAtPath:filepath contents:nil attributes:nil];    if (success) {        NSLog(@"Date文件创建成功");    }    NSFileHandle *fileHandle=[NSFileHandle fileHandleForWritingAtPath:filepath];//创建一个写入数据的fileHandle对象    NSTimer * timer = [NSTimer scheduledTimerWithTimeInterval:1 target:self         selector:@selector(timerAction:) userInfo:fileHandle repeats:YES];//创建一个timer对象，每隔一秒钟写入一条数据    [timer fire];//启动timer}-(void)timerAction:(NSTimer *)timer{    static int n=0;    NSFileHandle *fileHandle=timer.userInfo;    [fileHandle seekToEndOfFile];//设置文件偏移量到文件末尾        NSDate *nowDate=[NSDate date];//获取系统时间    NSDateFormatter *dateformate=[[NSDateFormatter alloc] init];//建立时间格式对象    [dateformate setDateFormat:@"yyyy/MM/dd HH/mm/ss"];    NSString *datestring=[dateformate stringFromDate:nowDate];//按格式字符串格式化获取的时间        NSLog(@"%@",datestring);        datestring=[datestring stringByAppendingString:@"\n"];//添加一个换行符    NSData *data=[datestring dataUsingEncoding:NSUTF8StringEncoding];    [fileHandle writeData:data];        if (n==10) {        [timer invalidate];//设置timer无效        [fileHandle closeFile];//关闭fileHandle    }    n++;        }@end