版本更新提示用户更新

判断itunes的版本号和当前项目的版本号是否一致，如果不一样则提示用户更新:

　　

// 提示用户更新
-(void)checkAppUpdate
{
NSDictionary *infoDict = [[NSBundle mainBundle] infoDictionary];

NSString *nowVersion = [infoDict objectForKey:@"CFBundleVersion"];
NSURL *url = [NSURL URLWithString:[NSString stringWithFormat:@"http://itunes.apple.com/lookup?id=%@", kStoreAppId]];
NSString * file = [NSString stringWithContentsOfURL:url encoding:NSUTF8StringEncoding error:nil];

NSRange substr = [file rangeOfString:@""version":""];
NSRange range1 = NSMakeRange(substr.location+substr.length,10);
NSRange substr2 =[file rangeOfString:@""" options:nil range:range1];
NSRange range2 = NSMakeRange(substr.location+substr.length, substr2.location-substr.location-substr.length);
NSString *newVersion =[file substringWithRange:range2];
if(![nowVersion isEqualToString:newVersion])
{
UIAlertView *alert = [[UIAlertView alloc] initWithTitle:@"提示" message:@"版本有更新"delegate:self cancelButtonTitle:@"忽略"otherButtonTitles:@"更新",nil];
[alert show];
}
}

- (void)alertView:(UIAlertView*)alertView clickedButtonAtIndex:(NSInteger)buttonIndex
{
if(buttonIndex==1)
{
// 此处加入应用在app store的地址，方便用户去更新，一种实现方式如下：

NSURL *url = [NSURL URLWithString:[NSString stringWithFormat:@"https://itunes.apple.com/us/app/che-yi/id1087016587?l=zh&ls=1&mt=8"]];
[[UIApplication sharedApplication] openURL:url];
}
}