Useful HTML

You can use the “onSubmit()” event handler in the form tag to do some form validation!

Place the “onSubmit()” event handler in the “Form” tag

<FORM ACTION="formdata.php" NAME="testform" onSubmit="return TestDataCheck()" >

for example you can use it like this

<SCRIPT TYPE="text/javascript">
<!--
// check that they entered an amount tested, an amount passed,
// and that they didn't pass units than they more than tested
 
function TestDataCheck()
{
var qtytested = parseInt(document.testform.qtytested.value);
var qtypassed = parseInt(document.testform.qtypassed.value);
var returnval;
 
if ( (qtytested >= 1) && (qtypassed >= 0) && (qtytested >= qtypassed)) 
   returnval = true;
else
   {
   alert("must enter the quantity tested and that amount or fewer for quantity passed");
   returnval = false;
   }
 
return returnval;
}
// -->
</SCRIPT>
 
<FORM ACTION="formdata.php" NAME="testform" onSubmit="return TestDataCheck()" >
units tested: <INPUT NAME="qtytested" SIZE=3><BR>
units passed: <INPUT NAME="qtypassed" SIZE=3><P>
<INPUT TYPE=SUBMIT VALUE="Submit">
</FORM>