empty validation

what is wrong with my empty validation function?

[swati]

What is wrong with the following function. When i click ok in the alert box the form should not get submitted but it does.
function emptyValidation(entered,alertbox){
with(entered){
if(value==null¦¦value==""){
if(alertbox!=""){
alert(alertbox);
}
return false;
} else{ return true;}
}
}

<form name="myForm" method="get" onsubmit="return emptyValidation(usage,"Please enter a value!")">
<input type="text" name="usage">
<input type="submit" name="go" value="go">
</form>

[Bernard Marx]

Possible probs:

1. Bad quote nesting.
2. Reference, usage, enough.

Try:

onsubmit="return emptyValidation(this.usage,'Please enter a value!')"

I don't like 'with', it's confusing. How about:

function emptyValidation(entered,alertbox)
{ 
  var value = entered.value;
  if(!value)// empty string is false 
  {
    if(alertbox)
      alert(alertbox); 
    return false; 
  } 
  else return true; 
}
// or // simply..
function emptyValidation(entered,alertbox)
{ 
  if(alertbox &&!entered.value) alert(alertbox);
  return!entered.value;
}

Oh the online editor again!
The line line should read:

return[space][excl!][excl!]entered.value;

[swati]

No its still not working, here s the code:(i m using mozilla firefox browser)
<script type="text/javascript" language="JavaScript">
function emptyValidation(entered,alertbox){
var value = entered.value;
if(!value)// empty string is false
{
if(alertbox)
alert(alertbox);
return false;
}
else return true;
}
</script>

<form name="myForm" method="get" onsubmit="return emptyValidation(this.usage,"Please enter a value!")">
<input type="text" name="usage" size=3>
<input type="submit" name="go" value="go">
</form>

[swati]

hey no no its working , i did not put the right quotes around 'please enter a value'
It works now.
Thank you so much....this is the best forum in the world!

[rocknbil]

Actually this poses a good question (ok, maybe an old one :D ) - all coding errors aside, why doesn't an obviously blank value evaluate as null or 'null' or '' sometimes?