判断ios程序第一次启动

方法有很多，但一列出一种

在didFinishLaunchingWithOptions里面写

if(![[NSUserDefaults standardUserDefaults] boolForKey:@"firstStart"]){

        [[NSUserDefaults standardUserDefaults] setBool:YES forKey:@"firstStart"];

        NSLog(@"第一次启动");

        UIAlertView *a = [[UIAlertView alloc]initWithTitle:@"1" message:nil delegate:self cancelButtonTitle:@"ok" otherButtonTitles:nil];

        [a show];

    }else{

        NSLog(@"不是第一次启动");

        UIAlertView *a = [[UIAlertView alloc]initWithTitle:@"2" message:nil delegate:self cancelButtonTitle:@"ok" otherButtonTitles:nil];

        [a show];

    }