iOS开发 点击跳转到App Store 或者 点击按钮去评价

//跳转到应用页面

NSString *str = [NSString stringWithFormat:@"http://itunes.apple.com/us/app/id%d",appid]; 

[[UIApplication sharedApplication] openURL:[NSURL urlWithString:str]];

 

//跳转到评价页面

NSString *str = [NSString stringWithFormat: @"itms-apps://ax.itunes.apple.com/WebObjects/MZStore.woa/wa/viewContentsUserReviews?type=Purple+Software&id;=%d",   

                         appid ];   

[[UIApplication sharedApplication] openURL:[NSURL urlWithString:str]];