您可以使用 NSUserDefaults 永久存储内容
NSUserDefaults *userDefaults=[NSUserDefaults standardUserDefaults];
[userDefaults setObject:Any object you want forKey:any Key you want];
[userDefaults synchronize];
当应用程序关闭或崩溃时,您可以通过添加通知来捕获它:
将此添加到您的 viewDidLoad
[[NSNotificationCenter defaultCenter] addObserver:self selector:@selector(saveCount) name:UIApplicationDidEnterBackgroundNotification object:nil];
[[NSNotificationCenter defaultCenter] addObserver:self selector:@selector(saveCount) name:UIApplicationWillTerminateNotification object:nil];
在 saveCount 方法中做保存部分
-(void)saveCount
{
NSUserDefaults *userDefaults=[NSUserDefaults standardUserDefaults];
[userDefaults setObject:[NSString stringWithFormat:@"%d",counter] forKey:@"saveCount"];
[userDefaults synchronize];
}
当你想再次读取变量时使用这个 - 可能在 ViewDidLoad
NSUserDefaults *userDefaults=[NSUserDefaults standardUserDefaults];
NSString *countString= [userDefaults objectForKey:@"saveCount"];
NSLog(@"Your Count: %@",count);
//checking if data in user defaults is not empty
if(countString.length>0)
{
count.text=count;
counter=[countString intValue];
}
else
{
//for first time
counter=0;
count.text=@"0";
}
假设每次按下按钮时 yourlocalCountVariable 都会增加。