Check for string in form field using JS

Question

I have a simple form validator that checks to make for some field values are present and it works great, however we have recently been getting lots of BOT submissions in the form of entering a URL in the "Name" fields. I tried inserting s function to look for "http://" in the first_name field string but the form ignores the check. Ideally I think it might make more sense to check for the "http://" value in any of the form fields just to really stick it back to the bot but am unsure how to call both functions at the same time for each field and stuck just getting it to recognize one.

Here is (most) of the validator itself.

function checkForm( form ){
  function BogusUrl(str) {
      var pattern = new RegExp('^(http?:\\/\\/)?'); // look for URL in string
      if(pattern.form.first_name(str)) {
          alert( 'First Name is Bogus' ); // for testing
      return false;
       }
}
if( isEmpty( form.first_name ) ){
    alert( 'First Name is required field!' );
    return false;
    }
    if( isEmpty( form.last_name ) ){
    alert( 'Last Name is required field!' );
    return false;
    }
return true;
}

Edited for Alex and Manolo suggestions:

function BogusUrl(str) {
var pattern = new RegExp('^https?:\\/\\/'); // look for URL in string
    if(str.match(pattern)) {
    //alert( 'First Name is Bogus' ); // for testing
    return false;
  }
}


function checkForm( form ){
 if( BogusUrl(form.first_name.value.match(pattern))) {
    alert( 'First Name is Bogus' );
    return false;
} 
return true;
}

Javascript validation doesn't allow you to get rid of bot submissions. You have to duplicate such validation on server side. — hindmost
– hindmost, Commented Jan 28, 2014 at 15:01

Alex · Accepted Answer · 2014-01-28 14:54:34Z

2

I think you're missing the match part of that:

if(form.first_name.value.match(pattern))

answered Jan 28, 2014 at 14:54

Alex

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1 Comment

bridgemanusa Over a year ago

Adding the "match" makes perfect sense, however the function still seems to be ignored and the script jumps to the next field for validation (see modified code block above).

Manolo · Accepted Answer · 2014-01-28 19:44:06Z

2

var pattern = new RegExp('^(http?:\\/\\/)?'); // look for URL in string

Here you're checking "htt" and optionally "p". You should do:

var pattern = new RegExp('^(https?:\\/\\/)?'); // look for URL in string

or just:

var pattern = new RegExp('^(http:\\/\\/)?'); // look for URL in string

In your second option, you're not using the str parameter in the function. You should do:

function BogusUrl(str) {
  var pattern = new RegExp('^(https?:\\/\\/)?'); // look for URL in string
  if(str.match(pattern)) {
  alert( 'First Name is Bogus' ); // for testing
  return false;
  }
}

Also, you are testing if the string contains http(s):// or not! ?, so you should delete the interrogant:

function BogusUrl(str) {
  var pattern = new RegExp('^https?:\\/\\/'); // look for URL in string
  if(str.match(pattern)) {
  alert( 'First Name is Bogus' ); // for testing
  return false;
  }
}

edited Jan 28, 2014 at 19:44

answered Jan 28, 2014 at 14:54

Manolo

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5 Comments

bridgemanusa Over a year ago

I thing your second option makes the most sens as it checks for both and have modified the function but for some reason it is going ignored. See my modified codeblock above.

bridgemanusa Over a year ago

Maybe my syntax is off trying to grab the form field value as it is still skipping over the first_name field 'if(form.first_name.str.match(pattern)) {'

Manolo Over a year ago

I don't see you calling BogusUrl function. Just declaring it.

bridgemanusa Over a year ago

Modified my codeblock again above to separate out the function and the call. Now it ignores all validation unless I remove the call.

Manolo Over a year ago

But, are you calling the checkForm( form ) function anywhere?

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