protected void ExcelImportWizard_ActiveStepChanged(object sender, EventArgs e)
 {
     if (ExcelImportWizard.ActiveStepIndex == 1)
     {
         CustomValidatorValidateMapping.Validate();
     }
 }
 protected void btnValidate_Click(object sender, EventArgs e)
 {
     CustomValidatorValidateMapping.Validate();
 }
 protected void ItemDropDown_SelectedIndexChanged(object sender, EventArgs e)
 {
     CustomValidatorValidateMapping.Validate();
 }