html - Disable button if txtbox validates -

edit

solved! @peter campbell pointing me in right direction (and doing of leg work me there). code changed this:

if string.isnullorempty(output)         exists = false     else         exists = true     end if     if string.isnullorempty(output) return string.empty     dim c gpcuser      if typeof httpcontext.current.session("customer") gpcuser         c = ctype(httpcontext.current.session("customer"), gpcuser)          if c.accountno > 0 return ""     end if 

by moving if statement sets 'exists' boolean before return statements, still fire correctly , validate emails properly, correctly disable button well.

end edit

i have page checks customer's email address see if it's in our database. if is, page should ask customer log-in email instead of continuing new account, doesn't prevent them continuing.

i disable continue button if email address in system can't figure out (i'm store's new web developer , there no documentation me existing site).

code below,

<%@ page language="vb" masterpagefile="~/standard-no-menu.master"    autoeventwireup="false" codefile="billing-details.aspx.vb" inherits="billing_details" %> 

"); --> "); -->

<script language="javascript" type="text/javascript">  function validateform() { if(document.getelementbyid('<%= lstpaymentoptions.clientid %>').selectedindex == "0") {     alert("please select  \"payment method\".");     document.getelementbyid('<%= lstpaymentoptions.clientid  %>').focus();     return (false); }  if (aforgotpwd.style.display != null && aforgotpwd.style.display.tostring() != "none") {     var emailele = document.getelementbyid("<%= txtemail.clientid %>");     emailele.focus();      return false; }    if(document.getelementbyid('<%= txtemail.clientid %>').value=="") {     alert("please enter value in field \"email\".");     document.getelementbyid('<%= txtemail.clientid %>').focus();     return (false); }  validemail=0; var checkstr = document.getelementbyid('<%= txtemail.clientid %>').value; (i = 0; < checkstr.length; i++) {     if(checkstr.charat(i)=="@")         validemail |= 1;     if(checkstr.charat(i)==".")         validemail |= 2; } if(validemail != 3) {     alert("please enter valid email address.");     document.getelementbyid('<%= txtemail.clientid %>').focus();     return (false); }   if(document.getelementbyid('<%= txtfirstname.clientid %>').value=="") {     alert("please enter value in field \"first name\".");     document.getelementbyid('<%= txtfirstname.clientid %>').focus();     return (false); }  if(document.getelementbyid('<%= txtlastname.clientid %>').value=="") {     alert("please enter value in field \"last name\".");     document.getelementbyid('<%= txtlastname.clientid %>').focus();     return (false); }</script> <asp:panel runat="server" defaultbutton="btncontinue">      <div class="billing-row"> <div class="cart-process-image"><img alt="" src="images/list_tick.gif"/></div> <div class="cart-process-text">shopping cart</div> <div class="cart-process-image"><img alt="" src="images/rightarrow.jpg"/></div> <div class="cart-process-text"><strong>personal , shipping details</strong></div> <div class="cart-process-image"><img alt="" src="images/rightarrow.jpg"/></div> <div class="cart-process-text">payment details</div> </div> <div class="billing-column-left">     <div class="billing-holder">         <div class="billing-row">             <p><strong>payment method</strong></p>             <div class="billing-column-mandatory">*</div>             <div class="billing-column-label">how pay?</div>             <div class="billing-column-textbox"><asp:dropdownlist id="lstpaymentoptions" runat="server" appenddatabounditems="true" cssclass="drop-down-list"></asp:dropdownlist></div>             <div><asp:requiredfieldvalidator id="paymentvalidator" runat="server"             controltovalidate="lstpaymentoptions" errormessage="please select payment method" forecolor="red" initialvalue="please select">         </asp:requiredfieldvalidator></div>                     </div>         </div>         <div class="billing-row">     </div>      <div class="billing-holder">         <p><strong>your contact details</strong></p>         <div class="billing-row">             <div class="billing-column-mandatory">&nbsp;</div>             <div class="billing-column-label">company / account name: </div>             <div class="billing-column-textbox"><asp:textbox name="txtaccountname" id="txtaccountname" maxlength="60" width="270" runat="server" cssclass="textbox"></asp:textbox></div>         </div>         <div class="billing-row">             <div class="billing-column-mandatory">*</div>             <div class="billing-column-label">email: <asp:requiredfieldvalidator id="emailvalidator" runat="server"             controltovalidate="txtemail" errormessage=" required" forecolor="red">         </asp:requiredfieldvalidator></div>             <div class="billing-column-textbox"><asp:textbox id="txtemail" maxlength="60"                      width="270" runat="server" cssclass="textbox" autopostback="true"></asp:textbox><b><a id="aforgotpwd" href="/forgotten-password.aspx" style="display:none">&nbsp;we have email address in our database. click here retrieve password?</a></b></div>         </div>         <div class="billing-row">         <div class="billing-column-mandatory">*</div>          <div class="billing-column-label">first name: <asp:requiredfieldvalidator id="firstnamevalidator" runat="server"             controltovalidate="txtfirstname" errormessage=" required" forecolor="red">         </asp:requiredfieldvalidator></div>         <div class="billing-column-textbox"><asp:textbox name="txtfullname" id="txtfirstname" maxlength="30" width="270" runat="server" cssclass="textbox"></asp:textbox></div>         </div>         <div class="billing-row">         <div class="billing-column-mandatory">*</div>         <div class="billing-column-label">last name: <asp:requiredfieldvalidator id="lastnamevalidator" runat="server"             controltovalidate="txtlastname" errormessage=" required" forecolor="red">         </asp:requiredfieldvalidator></div>         <div class="billing-column-textbox"><asp:textbox name="txtfullname" id="txtlastname" maxlength="30" width="270" runat="server" cssclass="textbox"></asp:textbox></div>         </div>     <div class="billing-holder">         <p><strong>additional information relating order.</strong></p>         <div class="billing-column-textfield"><asp:textbox textmode="multiline" width="463" height="212" runat="server" id="txtadditionalinfo" cssclass="textbox"></asp:textbox></div>         </div> </div> <asp:panel id="pnlverticalresponse" runat="server" visible="false"> <div class="billing-oos-background"> <div class="billing-row"> <asp:label id="lblsubscribe" runat="server" text="<p><strong>you not subscribed our newsletter:</strong>"></asp:label></div> <div class="billing-row"><asp:checkbox id="chksubscribe" runat="server" />   receive information , promotional material global pc</div></div> </asp:panel> <asp:panel id="pnloutofstockblurb" runat="server" visible="false" > <div class="billing-oos-background"><div class="billing-row"><asp:label id="lbloutofstockmessage" runat="server" text="<strong>items out of stock:</strong><p>you have ordered 1 or more items out of stock. normal procedure global pc hold order until items in stock , ship entire order @ once. however, if wish can elect have order split 2 shipments out of stock items arriving @ later date. order split 2 shipments?</p>"></asp:label></div> <div class="billing-row"><asp:radiobuttonlist id="radlistsplit" runat="server" cellspacing="5" autopostback="true" causesvalidation="true" onselectedindexchanged="radlistsplit_selectedindexchanged" cssclass="textbox" borderwidth="0px"><asp:listitem value="0" text="yes, want recieve order 2 separate deliveries"></asp:listitem><asp:listitem value="1" text="no, want wait , receive items @ once"></asp:listitem></asp:radiobuttonlist> <asp:requiredfieldvalidator id="splitvalidator" runat="server"             controltovalidate="radlistsplit" errormessage="please select 1 shipping option" forecolor="red">         </asp:requiredfieldvalidator> </div></div></asp:panel>  <div class="billing-row">     <div class="billing-button-cart">         <div class="green-button">             <a href="cart.aspx">back cart</a>         </div>     </div>     <div class="billing-button-checkout">         <div class="green-button">             <asp:linkbutton text="checkout" onclientclick="return validateform();" runat="server" id="btncontinue" />         </div>     </div> </div> </asp:panel>   </asp:content> 

vb.net

imports dataaccesslayer imports system.net imports system.data imports system.net.mail imports com.verticalresponse.api   partial class billing_details     inherits system.web.ui.page     protected c gpcuser     dim ismember boolean = false     dim bemember boolean = false     shared exists boolean = false       protected sub page_load(byval sender object, byval e system.eventargs) handles me.load         master.page.title += " - checkout"          dim listid integer         dim sessionid integer         dim vruser new vrapi()         dim newsession new loginargs()          newsession.username = "******@********.co.nz"         ' verticalresponse username         newsession.password = "**********"         'your verticalresponse password         ' objla.impersonate_user = "subaccount@emailaddress.com"; // if accessing or acting subaccount, uncomment , replace applicable email address.         newsession.session_duration_minutes = "120"         dim [date] datetime = datetime.now         listid = 284662333           if typeof session("customer") gpcuser             c = ctype(session("customer"), gpcuser)         else             c = new gpcuser         end if          if c.cartobjects.count <= 0             response.redirect("cart.aspx")         end if            if not page.ispostback                ' check shipping see if delivery details need displayed             if c.shippingmethodname "*pick-up*"                 pnlshippingdetails.visible = false             end if              'check if customer has ordered out of stock items             if c.intoutofstockitems >= 1                 pnloutofstockblurb.visible = true             else                 pnloutofstockblurb.visible = false             end if              txtemail.attributes.add("onblur", cstr(iif(c.accountno > 0, "", "callme(this.id,this.id);")))             lstpaymentoptions.datasource = sqlhelper.executedataset(system.configuration.configurationmanager.appsettings("dbconn"), "xw_getpaymenttypes").tables(0)             lstpaymentoptions.datatextfield = "ptdesc"             lstpaymentoptions.datavaluefield = "ptno"             lstpaymentoptions.items.insert(0, "please select")             'lstpaymentoptions.databind()              if c.customerid > 0                 'populate table                 txtaccountname.text = c.accountname                 txtfirstname.text = c.firstname                 txtlastname.text = c.lastname                 txtemail.text = c.email                 txtaddress.text = c.address                 txtcitytown.text = c.city                 txtsuburb.text = c.suburb                 txtpostcode.text = c.postcode                 txtphone.text = c.phone                 txtmobile.text = c.mobile                    try                     sessionid = vruser.login(newsession)                 catch ex system.exception                     'lblmessage.text = ex.tostring()                 end try                 dim getmember new getlistmemberbyemailaddressargs()                 getmember.session_id = sessionid                 getmember.list_id = listid                 getmember.email_address = txtemail.text                 try                     vruser.getlistmemberbyemailaddress(getmember)                     ismember = true                     pnlverticalresponse.visible = false                 catch ex system.exception                     ismember = false                     pnlverticalresponse.visible = true                 end try                  if (ismember = false)                     pnlverticalresponse.visible = true                 end if                   dim dt data.datatable = gpcuser.getaccount(c.accountno)                 if dt isnot nothing                     if dt.rows.count > 0                         dim dr data.datarow = dt.rows(0)                         if dr("creditstatus") > "0" , dr("stopcredit") = "n" , dr("credlimit") > "0"                             lstpaymentoptions.items.remove("please select")                             lstpaymentoptions.items.insert(0, new listitem("my global pc account", "99"))                             lstpaymentoptions.items.insert(0, "please select")                         end if                     end if                 end if                 dt.dispose()              end if         end if     end sub      'radiobuttons set whether customer wants split shipping     protected sub radlistsplit_selectedindexchanged(sender object, e system.eventargs) handles radlistsplit.selectedindexchanged         if radlistsplit.selectedindex = "0"             c.instructions = "**customer has selected split shipping**"          elseif radlistsplit.selectedindex = "1"             c.instructions = ""          end if     end sub      protected sub btncontinue_click(byval sender object, byval e system.eventargs) handles btncontinue.click          if typeof session("customer") gpcuser             c = ctype(session("customer"), gpcuser)         else             exit sub         end if          if chksubscribe.checked = true             dim listid integer = 284662333             dim ismember boolean = false               dim newsession new loginargs()             newsession.username = "austin@globalpc.co.nz"              ' verticalresponse username             newsession.password = "global2012"              'your verticalresponse password             ' objla.impersonate_user = "subaccount@emailaddress.com"; // if accessing or acting subaccount, uncomment , replace applicable email address.             newsession.session_duration_minutes = "120"              dim [date] datetime = datetime.now                ' generated creating service reference points verticalresponse wsdl.              dim vruser new vrapi()                ' let's try log in. login call return session id, use in subsequent calls.             dim sessionid string = nothing             try                 sessionid = vruser.login(newsession)               catch ex system.exception                 txtadditionalinfo.text = ex.tostring()                 exit sub             end try              dim getmember new getlistmemberbyemailaddressargs()             getmember.session_id = sessionid             getmember.list_id = listid             getmember.email_address = txtemail.text              try                 vruser.getlistmemberbyemailaddress(getmember)                 ismember = true             catch ex system.exception                 ismember = false             end try             if (ismember = false)                 dim nmember new listmember()                 nmember.list_id = listid                   dim memberdata nvpair() = new nvpair(2) {}                  memberdata(0) = new nvpair()                 memberdata(0).name = "email_address"                 memberdata(0).value = txtemail.text                  memberdata(1) = new nvpair()                 memberdata(1).name = "first_name"                 memberdata(1).value = txtfirstname.text                  memberdata(2) = new nvpair()                 memberdata(2).name = "last_name"                 memberdata(2).value = txtlastname.text                  nmember.member_data = memberdata                  dim objal new addlistmemberargs()                  objal.list_member = nmember                 objal.session_id = sessionid                  try                     vruser.addlistmember(objal)                  catch ex system.exception                     txtadditionalinfo.text = ex.tostring()                     exit sub                 end try              else               end if          end if          c.paymenttype = lstpaymentoptions.selectedvalue         c.customerorderno = txtordernumber.text         c.instructions += txtadditionalinfo.text         c.createcustomerdetails(txtaccountname.text, txtfirstname.text, txtlastname.text, txtemail.text, txtaddress.text, txtsuburb.text, txtcitytown.text, txtpostcode.text, txtphone.text, txtmobile.text, lstcountry.selectedvalue)         c.addshippingdetails(txtshippingfullname.text, txtshippingaddress.text, txtshippingcitytown.text, txtshippingsuburb.text, txtshippingpostcode.text, lstshippingcountry.selectedvalue)          if c.customerid = 0             dim strpassword string = ""             if c.generatedpassword <= ""                 strpassword = ucase(randompassword.generate(8, 8))                 c.generatedpassword = strpassword             else                 strpassword = c.generatedpassword             end if              gpcuser.addupdatecustomer(c)               dim dt datatable = gpcuser.getuser(c.email, strpassword)             if not dt nothing                 if dt.rows.count > 0                     c.updateuser(dt.rows(0)("custid"))                     dim obj object = session("customer")                     session("customer") = c                 else                  end if             else             end if              session("customer") = c         end if          sendupdateaccountemailmessage(c.emailcount)          '''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''           response.redirect("payment-details.aspx")     end sub       'email validation     <system.web.services.webmethod()> _     public shared function validateemail(email string) string         dim wbclient webclient = new webclient()         dim strurl string = configurationmanager.appsettings("websiteurlfull") + "/ajax/check_email_address.aspx?email=" + email         dim reqhtml byte()         reqhtml = wbclient.downloaddata(strurl)         dim objutf8 utf8encoding = new utf8encoding()         dim output string = objutf8.getstring(reqhtml)         if string.isnullorempty(output) return string.empty         dim c gpcuser          if typeof httpcontext.current.session("customer") gpcuser             c = ctype(httpcontext.current.session("customer"), gpcuser)             exists = false             if c.accountno > 0                  exists = true             end if             return ""         end if            return output     end function      'method send email globalpc     private sub sendmessage(fromemail string, fromemailname string, _    toemails string(), isbodyhtml boolean, message string, subject string)         dim mail mailmessage = new mailmessage         mail.from = new mailaddress(fromemail, fromemailname)          each toemail string in toemails             mail.to.add(new mailaddress(toemail))         next          mail.bcc.add(fromemail)         mail.isbodyhtml = isbodyhtml         mail.subject = subject         mail.body = message         dim s new smtpclient(system.configuration.configurationmanager.appsettings("mailserver"))         s.send(mail)     end sub       'sends email globalpc if customer updates account details.     private sub sendupdateaccountemailmessage(emailcount integer)         dim subject string = "alert : website user has updated details"         dim message string         message &= "account number " & c.accountno & " email address " & c.email & " has updated account. via page billing-details" & vbcrlf & vbcrlf         message += "account name : " & txtaccountname.text & vbcrlf         message += "first name : " & txtfirstname.text & vbcrlf         message += "last name : " & txtlastname.text & vbcrlf         message += "email : " & txtemail.text & vbcrlf         message += "address : " & txtaddress.text & vbcrlf         message += "suburb : " & txtsuburb.text & vbcrlf         message += "city town : " & txtcitytown.text & vbcrlf         message += "country : " & lstcountry.selectedvalue & vbcrlf         message += "postcode : " & txtpostcode.text & vbcrlf         message += "phone : " & txtphone.text & vbcrlf         message += "mobile : " & txtmobile.text & vbcrlf         message += vbcrlf & vbcrlf         message += "shipping information" & vbcrlf         message += "txtshippingfullname.text : " & txtshippingfullname.text & vbcrlf         message += "txtshippingaddress.text  : " & txtshippingaddress.text & vbcrlf         message += "txtshippingcitytown.text : " & txtshippingcitytown.text & vbcrlf         message += "txtshippingsuburb.text : " & txtshippingsuburb.text & vbcrlf         message += "txtshippingpostcode.text : " & txtshippingpostcode.text & vbcrlf         message += "lstshippingcountry.selectedvalue : " & lstshippingcountry.selectedvalue & vbcrlf         message += vbcrlf & vbcrlf         message += "more information" & vbcrlf         message += "order no: " & c.customerorderno & vbcrlf         message += "payment type: " & c.paymenttype & vbcrlf         message += "instructions: " & c.instructions & vbcrlf         message += vbcrlf & vbcrlf         message += "regards" & vbcrlf & vbcrlf & "globalpc admin team"          sendmessage(configurationmanager.appsettings("accountdetailsupdateemail"), "global pc", _                                 new string() {configurationmanager.appsettings("accountdetailsupdateemail")}, false, message, subject)     end sub        protected sub txtemail_textchanged(sender object, e system.eventargs) handles txtemail.textchanged          dim listid integer = 284662333         dim ismember boolean = false         dim newsession new loginargs()         newsession.username = "austin@globalpc.co.nz"         ' verticalresponse username         newsession.password = "global2012"         'your verticalresponse password         ' objla.impersonate_user = "subaccount@emailaddress.com"; // if accessing or acting subaccount, uncomment , replace applicable email address.         newsession.session_duration_minutes = "120"         dim [date] datetime = datetime.now         ' generated creating service reference points verticalresponse wsdl.          dim vruser new vrapi()          ' let's try log in. login call return session id, use in subsequent calls.         dim sessionid string = nothing          try             sessionid = vruser.login(newsession)         catch ex system.exception             'lblmessage.text = ex.tostring()         end try           dim getmember new getlistmemberbyemailaddressargs()         getmember.session_id = sessionid         getmember.list_id = listid         getmember.email_address = txtemail.text         try             vruser.getlistmemberbyemailaddress(getmember)             ismember = true             pnlverticalresponse.visible = false         catch ex system.exception             ismember = false             pnlverticalresponse.visible = true         end try      end sub      protected sub chksubscribe_checkedchanged(sender object, e system.eventargs) handles chksubscribe.checkedchanged          if chksubscribe.checked = true             bemember = true         else             bemember = false         end if      end sub end class 

looks email checked against current addresses here

'email validation     <system.web.services.webmethod()> _     public shared function validateemail(email string) string         dim wbclient webclient = new webclient()         dim strurl string = configurationmanager.appsettings("websiteurlfull") + "/ajax/check_email_address.aspx?email=" + email         dim reqhtml byte()         reqhtml = wbclient.downloaddata(strurl)         dim objutf8 utf8encoding = new utf8encoding()         dim output string = objutf8.getstring(reqhtml)         if string.isnullorempty(output) return string.empty         dim c gpcuser          if typeof httpcontext.current.session("customer") gpcuser             c = ctype(httpcontext.current.session("customer"), gpcuser)             exists = false             if c.accountno > 0                  exists = true             end if             return ""         end if 

so exists variable tells if address matched.

try adding page_load method

 if page.ispostback    if exists       btncontinue.enabled = false    end if  end if 

as page posted server after button click, check see if exists true , if disable button.

p.s. change username/password use configurationmanger.appsettings , put username in web.config.