How to Validate Numbers in JavaScript
Usage : Two simple JavaScript for validate numbers. The first JS use is_NaN() function for validation.
This function take both positive and negative numbers as number. But second function
take positive numbers only as number.
Compatibility :
JavaScript Code :
Insert this JavaScript in the head section of your html code.
<script type="text/javascript">
function check_is_number_1(){
if(isNaN(document.getElementById('textbox_1').value) == false){
alert("Ok. This is a number");
document.getElementById('textbox_1').focus();
return false;
} else {
alert("Error! This is not a number");
}
}
function check_is_number_2(){
var reg = /^[0-9]+$/;
if(reg.test(document.getElementById('textbox_2').value) == true){
alert("Ok. This is a number");
document.getElementById('textbox_2').focus();
return false;
} else {
alert("Error! This is not a number");
}
}
</script>
HTML Code :
<html>
<head>
<title>Validate Numbers </title>
</head>
<body>
Enter Number 1 : <input name="textbox_1" id="textbox_1" type="text" />
<input name="check" id="check" type="button" value="Check" onClick="check_is_number_1()"><br /><br />
Enter Number 2 : <input name="textbox_2" id="textbox_2" type="text" />
<input name="check_2" id="check_2" type="button" value="Check" onClick="check_is_number_2()">
</body>
</html>
Demo :
Enter Number 1 :
Enter Number 2 :
No comments:
Post a Comment