protected void ButtonDelete_Click(object sender, EventArgs e)
 {
     bool status = false;
     foreach (GridViewRow row in GridViewMessageBox.Rows)
     {
         CheckBox checkBox = (CheckBox)row.Cells[0].FindControl("CheckBoxMessage");
         if (checkBox.Checked)
         {
             HiddenField hiddenField = (HiddenField)row.Cells[0].FindControl("HiddenFieldMessage");
             string messageUserOID = hiddenField.Value;
             MessageCenter messageCenter = new MessageCenter();
             if (messageCenter.DeleteMessageUserByOID(Convert.ToInt32(messageUserOID))) status = true;
         }
     }
     if (status)
     {
         PopulateMessageBox();
     }
 }