ios 视图之弹窗

1,NSUserDefaults

    NSUserDefaults *user = [NSUserDefaults standardUserDefaults];    if ([[user objectForKey:@"userName"] isEqualToString:          self.userName.text] && [[user objectForKey:@"passWord"]           isEqualToString:self.passWord.text]) {      UIAlertView *alter = [[UIAlertView alloc] initWithTitle:       @"提示" message:@"登陆成功" delegate:self cancelButtonTitle:       @"确定" otherButtonTitles:nil, nil];        [alter show];    }else{        UIAlertView *alter = [[UIAlertView alloc] initWithTitle:       @"提示" message:@"登陆失败" delegate:self cancelButtonTitle:       @"确定" otherButtonTitles:nil, nil];        [alter show];    }