如何在C＃中将UserControl动态添加到窗体

Question

I am new to C#. I have Form1 and Form2 and UserControl1 . I want to dynamically add the UserControl1 to Form2 and show Form2 using ShowDialog but Form2 is shown empty. I know I can add UserControl1 to Form2 using Form2 constructor but I want to do it form Form1 .

Anyone knows how to do it?

This code is in Form1:

UserControl1 _UserControl1 = new UserControl1();

using (Form2 _Form2= new Form2 ())
 {

 _Form2.Controls.Add(_UserControl1);

 _Form2.ShowDialog();
  // Form2 is shown empty
 }

Answer 1

When creating controls at runtime, make sure the new control has all the necessary properties set. Location and Size are important, the control may be drawing off the form, or be tiny.

Also, make sure the control is not being hidden by another control. Make sure the Visible property is set true, and that there are no panels or other controls in the area that was specified for the control to be.

If there are other controls on the form, you can try setting the control's z-index using _Form2.Controls.SetChildIndex(_UserControl,0); Alternatively, if the control is intended to be on a panel, add the control to the panel's Controls collection.