change color of text box when value entered into text box

[rrrkkk]

Hello

Actually I am working on php I have created a insertion form in which I need when entering a value into bill amt text box then it should be compare with exp value if it is not equal then the color of bill amt text box should be change.

here is code

<?php
error_reporting(E_ALL^E_NOTICE);
$dbhost = "localhost";
$dbuser = "root";
$dbpass = "";
$dbname = "purchase";
mysql_connect($dbhost, $dbuser, $dbpass);
mysql_select_db($dbname) or die(mysql_error());
 
$qry_result= mysql_query("SELECT NRC FROM currentnfb") or die(mysql_error());
$row=mysql_fetch_array($qry_result);
$num=$row[NRC];
 
$description=$_POST['description'];
$number=$_POST['number'];
$text1=$_POST['text1'];
$year1=$_POST['year1'];
$text=$_POST['text'];
$fileno=$number. '-' .$text1. '/' .$year1. '/' .$text;
$Nameoffirm=$_POST['Nameoffirm'];
$exp=$_POST['exp'];
$year6=$_POST['year6'];
$month6=$_POST['month6'];
$day6=$_POST['day6'];
$dateofsanction=$year6. '-' .$month6. '-' .$day6;
$year5=$_POST['year5'];
$month5=$_POST['month5'];
$day5=$_POST['day5'];
$dateofpo=$year5. '-' .$month5. '-' .$day5;
$indentno=$_POST['indentno'];
$year=$_POST['year'];
$month=$_POST['month'];
$day=$_POST['day'];
$dateofindent=$year. '-' .$month. '-' .$day;
$billno=$_POST['billno'];
$year4=$_POST['year4'];
$month4=$_POST['month4'];
$day4=$_POST['day4'];
$dateofbillno=$year4. '-' .$month4. '-' .$day4;
$BLno=$_POST['BLno'];
$billpass=$_POST['billpass'];
$billamt=$_POST['billamt'];
if($billamt=$exp)
{
billamt.style.background='green';}
else
{
billamt.style.background='red';}
$year3=$_POST['year3'];
$month1=$_POST['month1'];
$day1=$_POST['day1'];
$dateofbill=$year3. '-' .$month1. '-' .$day1;
$availbal=$_POST['availbal'];
$progbal=$_POST['progbal'];
$remark=$_POST['remark'];
$availbal=$num;
$progbal=$num-$exp;
 
 
 
 
$query="insert into nfone(description,fileno,Nameoffirm,exp,dateofsanction,dateofpo,indentno,dateofindent,billno,dateofbillno,BLno,billpass,billamt,dateofbill,availbal,progbal,remark) values ('$description','$fileno','$Nameoffirm','$exp','$dateofsanction','$dateofpo','$indentno','$dateofindent','$billno','$dateofbillno','$BLno','$billpass','$billamt','$dateofbill','$availbal','$progbal','$remark')";
mysql_query($query)or die('error');
echo"database update with:" .$expend."".$availbal."".$progbal."".$billamt."";
$NRC=$progbal;
$sql = "UPDATE currentnfb
       SET NRC = '$progbal'";
       $retval = mysql_query( $sql);
if(! $retval )
{
  die('Could not update data: ' . mysql_error());
}
echo "Updated data successfully\n";
 
?>
 

[johny10151981]

how about onchange='this.style.color="newColor"'?