Checking to see if the input value matches any value within an array before returning true

Question

I'm trying to validate a form using javascript. Checking to see if the input value matches any value within an array before returning true.

Here's an example of what I have written so far. Yet this seems to not work.

<script type='text/javascript'>

function checkForm() 
{ 

var agent = document.getElementById('agent').value;

var myArray = new Array() 
  myArray[0] = 'First Agent';
  myArray[1] = 'Second Agent';
  myArray[2] = 'Third Agent';

if (agent != myArray) 
{
  alert("Invalid Agent");
  return false;
} 

else 
{
  return true;
}
}

<form>
<fieldset>
Agents Name*
<input type="text" size="20" name="agent" id="agent">
</fieldset>
</form>

I'd recommend using the jQuery Validate https://www.google.com/url?sa=t&rct=j&q=&esrc=s&source=web&cd=1&cad=rja&ved=0CDEQFjAA&url=http%3A%2F%2Fjqueryvalidation.org%2Fvalidate%2F&ei=lU2mUfD-JpK88wSjjoGQCw&usg=AFQjCNE43XLONaPQUHt0-BNtFoJG-FSa3Q&sig2=Rtm-Oa3AUbwRYDiWfwtyWA&bvm=bv.47008514,d.eWU plugin. I had a huge form that I needed to validate and this plugin made it quite easy to manage. — ckpepper02, May 29 '13 at 18:51

score 3 · Answer 1 · answered May 29 '13 at 18:49

3

You need to make a for structure to pass your entire array, when value matches you return true, otherwise return false. Something like this:

for (var i = 0; i < myArray.length; i++) {
    if (agent == myArray[i])
        return true;
}
return false;

answered May 29 '13 at 18:49

Wellington Zanelli

1,894
3
18
43

score 0 · Answer 2 · answered May 29 '13 at 18:46

0

function checkForm() {
    var agent = document.getElementById('agent').value;
    var myArray = ['First Agent', 'Second Agent', 'Third Agent'];
    if(myArray.indexOf(agent) == -1) //returns the index of the selected element 
    {
        alert("Invalid Agent");
        return false; // if you return false then you don't have to write the else statement
    }
    return true;
}

answered May 29 '13 at 18:46

Niccolò Campolungo

11,824
4
32
39

Thank you this has helped a lot – user2433761 May 29 '13 at 19:49

score -1 · Answer 3 · edited May 23 '17 at 12:08

-1

"agent != myArray" compares your string with an array, not with its contents. Look at this post: Determine whether an array contains a value

edited May 23 '17 at 12:08

Community

1
1

answered May 29 '13 at 18:50

lasote

591
2
12

score -2 · Answer 4 · answered Jan 18 '16 at 00:24

-2

With Underscore/lodash you could do:

if (_.indexOf(myArray,agent) == -1) 
{ 
   //alert invalid agent    
   ...
}

answered Jan 18 '16 at 00:24

Jafin

4,153
1
40
52

Checking to see if the input value matches any value within an array before returning true

4 Answers4