数据管理（1）

#import <Foundation/Foundation.h>

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

{

    @autoreleasepool {

        /**1 追加数据**/

       /*

        NSString *homePath = NSHomeDirectory();

        NSString *filePath = [homePath stringByAppendingString:@"/phone/phone.text"];

        NSLog(@"filePath = %@",filePath);

        NSFileHandle *fileHandle = [NSFileHandle fileHandleForUpdatingAtPath:filePath];

        

        [fileHandle seekToEndOfFile];

        //[fileHandle seekToFileOffset:3];

        NSString *str = @"追加数据";

        NSData *data = [str dataUsingEncoding:NSUTF8StringEncoding];

        [fileHandle writeData:data];

        

        NSLog(@"fileHandle=%@",fileHandle);

        [fileHandle closeFile];

        */

        /*2 定位读取数据 */

       /*

        NSString *homePath = NSHomeDirectory();

        NSString *filePath = [homePath stringByAppendingString:@"/phone/phone.text"];

        NSFileHandle *fileHandle = [NSFileHandle fileHandleForReadingAtPath:filePath];

        NSUInteger length = [fileHandle availableData].length;

        [fileHandle seekToFileOffset:length/2];

        NSData *data = [fileHandle readDataToEndOfFile];

        NSString *str = [[NSString alloc]initWithData:data encoding:NSUTF8StringEncoding];

        NSLog(@"%@",str);

         */

       /*复制文件*/

       NSString *homePath = NSHomeDirectory();

       NSString *filePath = [homePath stringByAppendingString:@"/phone/phone.text"];

       //创建目标路径

       NSString *targetPath = [homePath stringByAppendingString:@"/phone/cellPhone.text"];

       //创建目标文件

       NSFileManager *fileManager = [NSFileManagerdefaultManager];

       BOOL success = [fileManager createFileAtPath:targetPath contents:nilattributes:nil];

       if (success)

        {

            NSLog(@"creat success");

        }

        //创建两个fileHandle

        //一个用于读取文件

       NSFileHandle *outFileHandle = [NSFileHandlefileHandleForWritingAtPath:targetPath];

        //一个用于写文件

       NSFileHandle *inFileHandle = [NSFileHandlefileHandleForReadingAtPath:filePath];

       NSData *data = [inFileHandle readDataToEndOfFile];

        [outFileHandlewriteData:data];

        

       //关闭文件

        [outFileHandlecloseFile];

        [inFileHandlecloseFile];

        

    }

   return 0;

}