To create MDI form we have to open a form then we have to set the

property ‘IsMdiContainer’ of the form to ‘true’. The form will look like this.

this.IsMdiContainer = true;               

Now add menu, to add menu use menuStrip from tools.

Now, once the MDI form is created we need to do its coding.

Coding

    private void mdiRecords_Load(object sender, EventArgs e)
        {
                this.IsMdiContainer = true;               
                frmRecord fr = new frmRecord();
             //here setting child form MdiParent to this MDI form.
                fr.MdiParent = this;
                fr.Show();
        }

  Here, MDIParent1 is parent form and Record (frmRecord) is child form.