Help validating multi form

[Wednesdai]

##Background##
i am a complete noob with JS (i can slightly read it, but cant write it)

##Problem##
Link: http://s328792954.websitehome.co.uk//multi_step_form/

Im trying to make a multi-step form,
and i cam across a tutorial on-line which showed a basic example.

anyway.....

i've added a field for number only (loan amount)
but the coding i use is obviously wrong because now it will not accept any form of input

var fields = $('#first_step input[type=amountborrow]');
  var  numericExpression = /^[0-9]$/;
        var error = 0;
        fields.each(function(){
            var value = $(this).val();
            if( value.length<3 || value==field_values[$(this).attr('id')] || ( $(this).attr('id')=='amountborrow' && !numericExpression.test(value) ) ) {
                $(this).addClass('error');
                $(this).effect("shake", { times:3 }, 50);
                
                error++;
            } else {
                $(this).addClass('valid');
            }
        });

please help (sorry if this is wrong section i didnt really understand forum sections)

[venegal]

Your regexp is wrong:

var numericExpression = /^[0-9]$/;

It tests for only one single digit. Since you enforce a minimum length of 3, this is never true.

If you want to test that there are only digits in there, no matter how many, use this:

var numericExpression = /^\d*$/;