直接上代碼！

1.控制臺(tái)打印

NSString *idfa = [[ASIdentifierManager sharedManager].advertisingIdentifier UUIDString];
NSLog(@"本機(jī)idfa=%@",idfa);//控制臺(tái)查看

2.使用彈窗顯示并復(fù)制

NSString *idfa = [[ASIdentifierManager sharedManager].advertisingIdentifier UUIDString];

UIAlertController *alertController = [UIAlertController alertControllerWithTitle:@"本機(jī)IDFA" message:idfa preferredStyle:UIAlertControllerStyleAlert];
[alertController addAction:[UIAlertAction actionWithTitle:@"復(fù)制" style:UIAlertActionStyleDestructive handler:^(UIAlertAction * _Nonnull action) {
      UIPasteboard *pab = [UIPasteboard generalPasteboard];
      pab.string = idfa;
}]];
[[UIApplication sharedApplication].keyWindow.rootViewController presentViewController:alertController animated:YES completion:nil];