Validation for numeric data

technoguy · #1 (**permalink**) 03-13-2007, 05:08 AM

Is there anyone who can provide me code for validation for numbers only field?

Thank you

Tripy · #2 (**permalink**) 03-13-2007, 04:35 PM

What kind of validation. For it to be numeric only ?
Positive numeric only, or can it be negative too (like -20)

If it's strictly numeric, then isNan() is your friend.

Code:

var value=10;
var result=null;
//isNan() test if the parameter is NOT a number. So testing that a number is NOT not a number does the trick.
if(!isNan(value)){
  result=true;
}
else{
  result=false;
}

reference: http://docs.sun.com/source/816-6408-...ev.htm#1064024

technoguy · #3 (**permalink**) 03-13-2007, 04:46 PM

I am new to javascript. So plz advice , should I call javascript function on Submit button click event? I mean while submitting a forum?

Tripy · #4 (**permalink**) 03-13-2007, 08:00 PM

It's up to each one preferences.
There is not just 1 way of doing something.

I personally prefer to use a simple button, that will call a javascript fnuction that will do the submit, rather than a submit button that I will stop the effect later.
Simply the logic seems wrong to stop an action that have started.
I prefer to check it before.

Look at this bit of javascript:

Code:

<script type="text/javascript">
function submitForm(){
  var inputError=true;
  //For a text input
  var val1=document.getElementById('field1').value;
  //For a drop down select
  var sel1=document.getElementById('select1').options[document.getElementById('select1').selectedIndex].value
  //For a radio button
  for(i=0;i<document.getElementById('radio1').length;i++){
    if(document.getElementById('radio1').checked){
      var radio1=document.getElementById('radio1').value;
    }
  }
  
  //Now, do the checks you need with your values...
  ...
  if(1 == 1){
    //Just for the demo, we validate the datas
    inputError=false;
  }
  //And if there are no errors, simply submit the form
  if(inputError==false){
    document.getElementById('myForm').submit();
  }
}
</script>

This function goes with this form:

Code:

<form name="myForm" id="myForm" method="post" action="http://www.whatever.com"/>
  <input type="text" name="field1" id="field1"/><br/>
  <select name="select1" id="select1">
    <option value="1">First</option>
    <option value="2">Second</option>
    <option value="3">Third</option>
  </select><br/>
  <input type="radio" name="radio1" id="radio1" value="one"/><br/>
  <input type="radio" name="radio1" id="radio1" value="two"/><br/>
  <input type="radio" name="radio1" id="radio1" value="three"/><br/>
  <input type="button" value="click me, you fool" onclick="javascript:submitForm();"/>
</form>

And the combination of those two will make the form validated and submitted upon the click on the button, via the calling of the javascript function.

technoguy · #5 (**permalink**) 03-14-2007, 04:44 AM

Ok I have managed to validate for numeric data now. What I want to do now is when page is fully loaded cursor should go to first textbox automatically. I mean i want to set the focus on the text box. So that I dont have to click everytime inside the text box for typing there.