This property allows you to obtain references to all the MDI child forms currently opened in an MDI parent form. To create an MDI child form, assign the System.Windows.Forms.Form that will be the MDI parent form to the Form.MdiParent property of the child form.

You can use this property to loop through all the MDI child forms to perform operations such as saving data to a database when the MDI parent form closes or to update fields on the child forms based on actions performed in your application.