HTML5 form controls
From HTML5 the control of forms is possible directly in the html input thanks to the pattern attribute and its value in the form of a regex. A regex is a regular expression, in other words a very powerful text control filter verifying the validity of information. Before HTML5, control of forms had to be done in JavaScript and its use was less convenient. The pattern attribute is compatible on browsers: Firefox 4+ Chrome 5+ Opera 9.6+ Internet explorer 10+…