iOS 不用跳转appstore直接app内下载应用

1、#import
2、SKStoreProductViewControllerDelegate

3、
//首先实例化一个VC
SKStoreProductViewController *storeVC = [[SKStoreProductViewController alloc] init];
//然后设置代理，注意这很重要，不如弹出就没法dismiss了
storeVC.delegate = self;
//接着弹出VC
[self presentViewController:storeVC animated:YES completion:nil];
//最后加载应用数据
[storeVC loadProductWithParameters:@{SKStoreProductParameterITunesItemIdentifier:@(1382195436)} completionBlock:^(BOOL result, NSError * _Nullable error) {
if (error) {
//handle the error
}
}];

4、

• (void)productViewControllerDidFinish:(SKStoreProductViewController *)viewController {
  //在代理方法里dismiss这个VC
  [viewController dismissViewControllerAnimated:YES completion:nil];
  }