您在主页上是什么意思?

What you mean in the main page?

如果您在按钮上打开表单，则该表单将在您拥有的页面顶部打开.

If you open a form on button click it will open on top of the page you have.

因此form2.Show()将打开表单，并在form2的关闭按钮中单击，您可以说this.Close()/this.Hide()

So form2.Show() will open the form and in form2's close button click you can say this.Close() / this.Hide()