Form value validation and onsubmit action : Form Validation « Form Control « JavaScript DHTML






  1. JavaScript DHTML
  2. Form Control
  3. Form Validation

Form value validation and onsubmit action

 

<html>
<head>
<title>Form Validation</title>
<script type="text/javascript">
function checkValid() {
    var cityField = document.forms[0]["city"];
    if (cityField.value != "Van") {
        var cityDiv = document.getElementById("citydiv");
        cityDiv.style.fontWeight = "bold";
        return false;
    } else {
        return true;
    }
}

</script>
</head>
<body>
<form name="formexample" id="formexample" action="#">
<div id="citydiv">City: <input id="city" name="city"></div>
<div><input id="submit" type="submit"></div>
</form>
<script type="text/javascript">
    function init() {
        document.forms[0].onsubmit = function() { return checkValid(this) };
    }
    window.onload = init;
</script>
</body>
</html>








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