parseInt with substr do not detect type on input

(index):34 Uncaught TypeError: Cannot read property ‘length’ of null

So the main goal i when write on textarea count on status div. I saw on many tutorial use with it parseInt and substr for get the number string from to.

Any idea why not work? And also what wrong with error above?


Your link doesn’t work.

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  var type = $(this).val().match(/\d/g).length.substr(0, limit);

When $(this).val() does not contain a number, $(this).val().match(/\d/g) is null, so you can’t get its length.
When it does contain a number, $(this).val().match(/\d/g).length is a number and you can’t take a substring of it.

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@design Not sure exactly what you are trying to do, but if you want to show the difference in the maxlength attribute value of the textarea and how many numbers that have been typed, you could do:

$('textarea').keyup('keypress', function() {
  var limit = parseInt($(this).attr('maxlength'));
  var numbersMatch = $(this).val().match(/\d/g);
  var numbersTyped = numbersMatch && numbersMatch.length;
    .html(`<small>You have ${limit - numbersTyped} typed numbers remaining.</small>`)
    .fadeIn(500, 'linear');
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${limit - numbersTyped}
Is a new style? for paste var? Other than '+ var +'


If you have not already done so, you should check out Free Code Camp’s ES6 section of the JavaScript and Algorithms certification. There are several newer features in ES6 that you could be using now in your applications. One of those is template literals, which is covered in that section.

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