public static ManageBrand createInstance()
 {
     if (manageBrand == null)
     {
         manageBrand = new ManageBrand();
     }
     return(manageBrand);
 }
        private void manageBrandBtn_Click(object sender, EventArgs e)
        {
            ManageBrand manageBrand = ManageBrand.createInstance();

            manageBrand.ShowDialog();
            if (manageBrand.Focused == false)
            {
                this.Focus();
                loadBrands();
            }
        }