When Updating gridview i need to get the OLD and NEW value of template field before Update

HI Experts.. :)
I have a project now.. need to update gridview with template field.
on my update method, i need to get the value of the OLD AND NEW template field
Before update the template field is a link button and a label, but when edit is click it will become text box(No issue on this)
but when i click the update button, i can only get the NEW VALUE of the template field and I cannot get the OLD value of the LINK BUTTON and the LABEL.
PLEASEEE HELLLPPP!
string s_BadgeNo = lbl_BadgeNo.Text; GridViewRow row = grdItems.Rows[e.RowIndex]; string NewPartNo = ((TextBox)(row.Cells[i_p_pn].FindControl("lnkPartNoList"))).Text; string NewPartDesc = ((TextBox)(row.Cells[i_p_desc].FindControl("txtDesc"))).Text; string Remarks = ((TextBox)(row.Cells[i_p_remarks].Controls[0])).Text; DataControlFieldCell cell = row.Cells[i_p_pn] as DataControlFieldC ...