JSFiddle - React, Tailwind, and code Playground

HTML

<fieldset>
    <input id="username" type="text" value="something"  />
</fieldset>

JavaScript

$('#username').blur(function() {
    var zipReg = "^[ABCDEGHJKLMNPRSTVXYabcdeghjklmnprstvxy][0-9][A-Z] [0-9][A-Z][0-9]$";
    var regex1 = new RegExp(zipReg);
    var zipReg = "^[ABCDEGHJKLMNPRSTVXYabcdeghjklmnprstvxy][0-9][A-Z][0-9][A-Z][0-9]$";
    var regex2 = new RegExp(zipReg);
    if (regex1.test(this.value) || regex2.test(this.value)) {
        alert("Code Postal OK");
    } else {
        alert("Erreur Code Postal");
    }
});