<script
language="javascript"
type="text/javascript">
function
validate(){
var
digits="0123456789"
var
temp
if
(document.testform.Name.value=="")
{
alert("No
Name !")
return
false
}
if
(document.testform.age.value=="")
{
alert("Invalid
Age !")
return
false
}
for
(var
i=0;i<document.testform.age.value.length;i++){
temp=document.testform.age.value.substring(i,i+1)
if
(digits.indexOf(temp)==-1){
alert("Invalid
Age !")
return
false
}
}
return
true
}
</script>
<FORM
name="testform"
onSubmit="return
validate()">
Name:<input
type="text"
size=30
name="Name">
Age:<input
type="text"
size=3
name="age">
<input
type="submit"
value="Submit">
</FORM>