title: How to insert space every 4 characters for IBAN registering?
body: <p>I'm really new in JavaScript and I would like to add to my input text, space insertion for IBAN account registering.</p>
  
  <p><div class="snippet" data-lang="js" data-hide="false" data-console="true" data-babel="false">
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  <pre class="snippet-code-html lang-html prettyprint-override"><code>&lt;input type="text" name="iban" onkeyup="if(this.value.length &gt; 34){this.value=this.value.substr(0, 34);}" /&gt;</code></pre>
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  </p>
  
  <p>There is my input field; could someone tell me how I can do this?</p>