Conflict with server-side and client-side validation

Question

I'm working in a ColdFusion 11 environment. I want to make a form, that when submitted, validates whether the value I'm entering is already in the database. I think I'm mixing up server-side and client-side and that is the cause of the problem.

query :

<cfquery name="FindIdMailExist" datasource="#application.zips_database#" username="#application.zips_username#" password="#application.zips_password#">
    SELECT *
    FROM users
    WHERE user_name = '#userName#'
</cfquery>

My javascript (client-side) + some CF code (server-side) :

   <script>
    function CheckSub()
    {
        alert("submited");
        return true;
    }
    function checkName(formObject, formField, fieldValue)
    {
        <cfoutput>
        alert('#FindIdMailExist.RecordCount#');
        </cfoutput>

        return true;
    }
  <script>

My form :

<cfform  onsubmit="CheckSub()" name="form">
    <br>
<table>
  <tr><td width="120" align="right">Name:</td><td><cfinput name="userName"type="text" onvalidate="checkName" message="pas  email"></td></tr>
  <tr><td><cfinput name="Submit" type="submit" value="Register"></td></tr>

</table>

</cfform>

So everything is working well expect for one thing. If you understand the code, an alert is displayed with the result of 1 or 0. 1 = yes the database already contains this name. 0 = no, the database doesn't already have it. The problem is when I click submit the result is 1 submit later.

example :

• Enter an already existing name and click submit : result = 0 (wrong one)
• Enter nothing : result 1 (the result is always the one I submitted before)

So maybe it impossible to validate server side before submitting the form? I want to make sure everything is good before sending my form to add the data to the database. I want to do this server-side for the safety.

Can anyone suggest a better way?

Thank you for your help!

Answer 1

Try with the below code and function: Keep the FindIdMailExist.RecordCount in a hidden field:

<cfoutput>
   <input type="hidden" name="hdnFindIdMailExist" 
        id="hdnFindIdMailExist" value="#FindIdMailExist.RecordCount#">
</cfoutput>

Now the above field will be in the form when clicking on submit. Try to modify the function in below way

function checkName(formObject, formField, fieldValue)
    {
        var testid = document.getElementById('hdnFindIdMailExist').val();
        alert(testid);
        return true;
    }

Took a variable and assigned the variable with the form element value and gave an alert. It is not a good practice to keep <cfoutput> in the javascript which may not sometimes access. Secondly it will not accept ## symbols in alert.