////FileInfo.m//MemoryManage////Created by macos on 14-8-10.//Copyright (c) 2014年 macos. All rights reserved.//#import"FileDemo.h"@implementationFileDemo-(id) init
{if(self =[super init]) {
NSFileManager*mgr =[NSFileManager defaultManager];
NSString*path = [NSHomeDirectory() stringByAppendingString:@"/mac.text"];
NSLog(@"%@",path);
NSString*data=@"abcdefghijklmn";
[mgr createFileAtPath:path contents:[data dataUsingEncoding:NSUTF8StringEncoding] attributes:Nil];//NSFileHandle无法创建文件NSFileHandle *file =[NSFileHandle fileHandleForUpdatingAtPath:path];
NSLog(@"%@",[[NSString alloc] initWithData:[file readDataToEndOfFile] encoding:NSUTF8StringEncoding]);
[file seekToFileOffset:0];
NSLog(@"length:%lu",[file availableData].length);
[file seekToEndOfFile];
NSDateFormatter*datefmt =[[NSDateFormatter alloc] init];
[datefmt setDateFormat:@"yyyy-MM-dd HH:mm:ss"];
NSString*ndata=[datefmt stringFromDate:[NSDate date]];
[file writeData:[ndata dataUsingEncoding:NSUTF8StringEncoding]];
[file seekToFileOffset:0];
[self copyFileToPath:file ToPath:[NSHomeDirectory() stringByAppendingString:@"/mac.bak.text"]];
[file closeFile];
}returnself;
}-(BOOL) copyFileToPath:(NSFileHandle *)srcFile ToPath:(NSString *)path
{
NSFileManager*fm =[NSFileManager defaultManager];//创建新的空文件NSFileHandle *newFile =[fm createFileAtPath:path contents:[srcFile readDataToEndOfFile ] attributes:nil];
[newFile closeFile];returntrue;
}@end