winform click to select all

code show as below:

 #region select all
         // chkAll_Checked is the click event of the select all key 
        private  void chkAll_CheckedChanged( object sender, EventArgs e)
        {
            if (chkAll.Checked)
            {
                chkSun.Checked = true;
                chkMon.Checked = true;
                chkThu.Checked = true;
                chkTue.Checked = true;
                chkWed.Checked = true;
                chkFri.Checked = true;
                chkSat.Checked = true;
            }
            else
            {
                chkSun.Checked = false;
                chkMon.Checked = false;
                chkThu.Checked = false;
                chkTue.Checked = false;
                chkWed.Checked = false;
                chkFri.Checked = false;
                chkSat.Checked = false;
            }
        }
        #endregion