foreach (Form childForm in MdiChildren)
{
childForm.Close();
}
Form2 obj= new Form2();
obj.MdiParent = this;
obj.Show();
Loading
// Create a new form to represent the child form
frmChild frm = new frmChild();
// Make the new form a child form. frm.MdiParent = this;
// Display the child form. frm.Show();
from parent
child.show(this);