UIAlertView 自动消失

- (IBAction)submit:(id)sender {

UIAlertView *alertview=[[UIAlertView
alloc]initWithTitle:@"提交成功!" message:@"使用中如有疑问，欢迎拨打我们的400电话！\n(三秒钟自动跳转)"
delegate:nil cancelButtonTitle:nil otherButtonTitles:nil,
nil];
[alertview
show];
[self
performSelector:@selector(dimissAlert:)
withObject:alertview
afterDelay:3];
}

- (void)dimissAlert:(UIAlertView *)alert {

if(alert) {

[alert dismissWithClickedButtonIndex:[alert
cancelButtonIndex] animated:YES];
}
}