Hi Please find the following code for numeric entry validation in javascript

function validateBox(){
        var data=document.myForm.someText.value;
        if(data=="" || data==null){
            alert("Please Input Data");
            document.myForm.someText.focus();
            return false;
        }
        if(data!="" || data!=null || is_numeric(data)){
                alert("Please Input Numeric Data");
                document.myForm.someText.focus();
                return false;
    }
}