Form validation using jquery, php and sql - php

Question

I am trying to validate part of a form, I am stuck on checking the database to see if a company name exists before submitting the form. This is a stripped down demo from the jquery ui modal from with the addition of checking if the company already exists. I am aware of SQL injection and am not doing anything about it just yet. At the moment the form won't submit as I'm missing something, I just don't know what yet.
Any help would be much appreciated.
This is what I have so far
The JS code:
$(function() {
var dialog, form,
company_name = $( "#company_name" ),
tips = $( ".validateTips" );
function updateTips( t ) {
tips
.text( t )
.addClass( "ui-state-highlight" );
setTimeout(function() {
tips.removeClass( "ui-state-highlight", 1500 );
}, 500 );
}
function checkCompany( o, n ) {
$.ajax({
type: "POST",
url: "crud.php?act=check",
data: "&company_name=" + o.val(),
success: function(response){
if(response > 0){
o.addClass( "ui-state-error" );
updateTips( n );
return false;
} else {
return true;
}
}
})
}
function addUser() {
var valid = true;
valid = valid && checkCompany( company_name, "Company Name already exists." );
if ( valid ) {
$.ajax({
type: "POST",
url: "crud.php?act=create",
data: "&company_name=" + company_name.val(),
success: function(data){
}
});
dialog.dialog( "close" );
}
return valid;
}
dialog = $( "#dialog-form" ).dialog({
autoOpen: false,
height: 350,
width: 350,
modal: true,
buttons: {
"Create an account": addUser,
Cancel: function() {
dialog.dialog( "close" );
}
},
close: function() {
form[ 0 ].reset();
allFields.removeClass( "ui-state-error" );
}
});
form = dialog.find( "form" ).on( "submit", function( event ) {
event.preventDefault();
addUser();
});
$( "#create-user" ).button().on( "click", function() {
dialog.dialog( "open" );
});
});
The php side (crud.php):
include 'connection.php';
$action = $_GET['act'];
if(isset($_POST['company_name'])){
$company_name = $_POST['company_name'];
}
switch($action){
case 'create':
$q = "INSERT INTO company_info (company_name) VALUES
('".$company_name."')";
mysql_query($q);
break;
case 'check':
$result = mysql_query('SELECT company_name FROM company_info WHERE company_name = "'.$company_name.'"');
$num = mysql_num_rows($result);
echo $num;
break;
}

Answer 1

CheckCompany returns nothing. You are returning true or false from success but that goes nowhere.
You need an outer deferred so you can return something from your ajax success, back through checkcompany out to your call.
Basically, checkcompany is called and exits/returns normally. SOme time later, the success function runs but that is independent because it's async. It's not part of your checkcompanmy function.
Ideally, you should trigger an event on ajax success that your element subscribes to.
Examples from comment below:
checkCompany(o,n) {
var retval = false;
$.ajax({
sync : true,
success: function(data) {
retval = true;
}
});
return retval;
}
OR asynch:
checkCompany(o,n) {
$.ajax({
success: function(data) {
$("#ID").trigger('ajsuccess.company');
}
});
}
OR using returned promise:
if (valid) {
checkCompany().done(function() {
do the secondary ajax call in here
}
}
checkCompany(o,n) {
return $.ajax();
}