IOS之数据持久化一
- (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]]) //如果文件中有，就从文件中取出来,从文件中读取
{
NSArray *arr = [NSArray arrayWithContentsOfFile:[self FilePath]];
t1.text = [arr objectAtIndex:0];
t2.text = [arr objectAtIndex:1];
t3.text = [arr objectAtIndex:2];
}
NSLog(@"%@",[self FilePath]);
//后台运行
[[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];//把数据存到文件中
}
-(NSString *)FilePath
{
//document路径
NSString *docPath = [NSSearchPathForDirectoriesInDomains(NSDocumentDirectory, NSUserDomainMask, YES) objectAtIndex:0];
NSString *path = [docPath stringByAppendingPathComponent:@"texs"];
return path;
}
