For checking all the rows in a gridview to check for already existing Identical values

int rowindex = GVRules.SelectedIndex;
        foreach (GridViewRow gvrow in GVRules.Rows)
        {
            if (gvrow.RowIndex != rowindex)
            {
                if (DdlRule.SelectedValue == GVRules.DataKeys[gvrow.RowIndex].Values[2].ToString()

&& DdlMemPrmZone.SelectedItem.Text == gvrow.Cells[2].Text && DdlMemProvZone.SelectedItem.Text ==

gvrow.Cells[3].Text)
                {
                    Label1.Text = "Rule " + DdlRule.SelectedItem.Text + " for Member Premium Zone "

+ DdlMemPrmZone.SelectedItem.Text + " and Member Provider Zone " + DdlMemProvZone.SelectedItem.Text

+ " is already added to this Policy !!";
                    return false;
                }
            }

        }