Numeric Validation in Java Script

In your html page add the control you want to validate but for this sample I used textbox to demonstrate this code, in my textbox control I used onkeyup event to validate whether recently entered charecter is numeric or not. so you can call this JavaScript code as your requirement in your project

Test.html

<input type="text" id="txt" name="txt" onkeyup="txtValidate(this.id)"/>
 

JavaScript Code
 

function txtValidate(txtid) {

        var ok = 0;

        var a = document.getElementById(txtid).value;

 

        for (var i = 0; i <= a.length - 1; i++) {

            var j = a.charCodeAt(i);

            for (var k = 48; k <= 57; k++) {

                ok = 0;

                if (k == j) {

                    ok = 1;

                    break;

                }

            }

 

        }

        if (ok == 0) {

            alert("Only Numeric Values Allowed");

            document.getElementById(txtid).value = "";

            for (var i = 0; i < a.length - 1; i++) {

                var j = a.charCodeAt(i);

                for (var k = 48; k <= 57; k++) {

                    ok = 0;

                    if (k == j) {

                        document.getElementById(txtid).value += a.charAt(i);

                    }

                }

 

            }

        }

    }



I hope this code helps you.

Thank you.