IOS之資料持久化一

- (void)loadView

{

    UIView *aView = [[UIView alloc] initWithFrame:CGRectMake(0, 0, 320, 480)];

    aView.backgroundColor = [UIColor whiteColor];

    self.view = aView;

    [aView release];

    

    t1 = [[UITextField alloc]initWithFrame:CGRectMake(80, 30, 80, 30)];

    t1.borderStyle = UITextBorderStyleRoundedRect;

    t1.text = @"";

    [aView addSubview:t1];

    

    t2 = [[UITextField alloc]initWithFrame:CGRectMake(80, 120, 80, 30)];

    t2.borderStyle = UITextBorderStyleRoundedRect;

    t2.text = @"";

    [aView addSubview:t2];

    

    t3 = [[UITextField alloc]initWithFrame:CGRectMake(80, 210, 80, 30)];

    t3.borderStyle = UITextBorderStyleRoundedRect;

    t3.text = @"";

    [aView addSubview:t3];

    

    NSFileManager *fm = [NSFileManager defaultManager];

    if ([fm fileExistsAtPath:[self FilePath]]) //如果檔案中有，就從檔案中取出來,從檔案中讀取

    {

        NSArray *arr = [NSArray arrayWithContentsOfFile:[self FilePath]];

        

        t1.text = [arr objectAtIndex:0];

        t2.text = [arr objectAtIndex:1];

        t3.text = [arr objectAtIndex:2];

        

    }

    NSLog(@"%@",[self FilePath]);

   //後台運行

    [[NSNotificationCenter defaultCenter] addObserver:self selector:@selector(saveData) name:UIApplicationDidEnterBackgroundNotification object:nil];

    

     

    

}

-(void)saveData

{

    NSArray *texts = [NSArray arrayWithObjects:t1.text,t2.text,t3.text, nil];

    [texts writeToFile:[self FilePath] atomically:YES];//把資料存到檔案中

}

-(NSString *)FilePath

{

    //document路徑

    NSString *docPath = [NSSearchPathForDirectoriesInDomains(NSDocumentDirectory, NSUserDomainMask, YES) objectAtIndex:0];

    

    NSString *path = [docPath stringByAppendingPathComponent:@"texs"];

    

    return path;

    

    

}