vb.net - VB 2008 Transferring stored values to textbox after initial textbox value is cleared -

self teaching vb beginner here.

i have data entry section includes...

2 comboboxes(cbx_trucktype, cbx_doornumber)

-------cbx_trucktype having 2 options (inbound, outbound)

-------cbx_doornumber having 3 options (door 1, door 2, door 3)

2 textboxes (txb_customername, txb_ordernumber)

-------txb_customername hold customer name

-------txb_ordernumber hold order number

and finally...

a button(btn_entertruck) transfers text comboxes , textboxes following...

2 tabs

the 1st tab has

2 buttons(btn_door1, btn_door2)

btn_door1 has 3 corresponding textboxes

-------txb_trucktypedoor1, txb_customernamedoor1, txb_ordernumberdoor1

btn_door2 has 3 corresponding textboxes

-------txb_trucktypedoor2, txb_customernamedoor2, txb_ordernumberdoor2

the 2nd tab has

1 button(btn_door3)

btn_door1 has 3 corresponding textboxes

-------txb_trucktypedoor3, txb_customernamedoor3, txb_ordernumberdoor3

currently, have code (that works question had!) that, upon btn_entertruck.click, transfer text corresponding textboxes.

here's problem...

i've coded msgbox pop-up (when inbound selected cbx_trucktype) asking if there outbound. if click "yes", inputbox pops-up , asks order number. button transfers inbound information textboxes , stores outbound order number.

when click btn_door1(or 2 or 3), clears text corresponding textboxes. (using me.controls)

( add code of above, figure moot point, because works)

what want happen...

i want have stored outbound number saved reference door number corresponds to. upon btn_doorx click, fill order number corresponding textbox. don't need text stored/saved when app closed.

and have no idea how that.

*after tooling, i've done following, not work"

i declared these @ class level.

    dim str_sametruckpodoor1, str_sametruckpodoor2, str_sametruckpodoor3 string 

this code in btn_entertruck event

    dim str_erroutdoorname string = cbx_doornumber.text      dim str_outbounddoorname string = str_erroutdoorname.replace(" ", "")      dim arrayforponumbers control() = me.controls.find("str_sametruckpo" & str_outbounddoorname, true)      if cbx_trucktype.text = "inbound"          dim outboundmsg = "is there outbound truck information?"          dim title = "outbound?"          dim style = msgboxstyle.yesno or msgboxstyle.defaultbutton2 or _             msgboxstyle.question          dim response = msgbox(outboundmsg, style, title)          if response = msgboxresult.yes              dim needpomessage, needpotitle, defaultvalue string             dim ponumberoutbound string              ' set prompt.             needpomessage = "enter po number"              ' set title.             needpotitle = "po# outbound"             defaultvalue = "?"   ' set default value.              ' display message, title, , default value.             ponumberoutbound = inputbox(needpomessage, needpotitle, defaultvalue)              ' if user has clicked cancel, set myvalue defaultvalue              if ponumberoutbound "" ponumberoutbound = defaultvalue              arrayforponumbers(0) = ponumberoutbound          end if      end if 

i'm getting error message on

    arrayforponumbers(0) = ponumberoutbound ' cannot convert string .controls 

and have following code in btn_door1 event - handles btn_door2, btn_door3

    dim whichbutton button = ctype(sender, button)      dim str_errdoorname string = whichbutton.name      dim str_doorname string = str_errdoorname.replace("btn_", "")      dim str_doortype control() = me.controls.find("txb_" & str_doorname & "type", true)      dim str_customer control() = me.controls.find("txb_" & str_doorname & "customer", true)      dim str_ordernumber control() = me.controls.find("txb_" & str_doorname & "ordernumber", true)      dim secondarrayforponumbers control() = me.controls.find("str_sametruckpo" & str_doorname, true)      if str_doortype(0).text = "outbound"          str_doortype(0).text = ""         str_customer(0).text = ""         str_ordernumber(0).text = ""      elseif secondarrayforponumbers(0).text.length > 0          str_doortype(0).text = "outbound"         str_ordernumber(0).text = me.controls("str_sametruckpo" & str_doorname).text      end if 

any appreciated. if i'm not clear on i'm asking or haven't given enough details, please let me know.

edit: added info based on comment, added code, changed title

how long want data stored? ie: longer life of open application? if application closed alright if data lost? if not, may want consider writing data external database.