Sample PHP Code: Formula Calculation with Online Charting / With chart

<?xml version="1.0" encoding="utf-8"?>

<?php

  function isBetween($val, $a, $b)

  {  

    if (is_numeric($val))

    {

      return floatval($val) >= $a && floatval($val) <= $b ? floatval($val) : "false";

    }

    else

      return false;

  }

 

  $monthly_savings = isBetween($_POST["txtMonthly_Savings"], 1, 100000)?$_POST["txtMonthly_Savings"]:100;

  $annual_investment_growth_rate = isBetween($_POST["txtAnnual_Investment_Growth_Rate"], 0, 1)?$_POST["txtAnnual_Investment_Growth_Rate"]:0.05;

  $annual_salary_increase_rate = isBetween($_POST["txtAnnual_Salary_Increase_Rate"], 0, 1)?$_POST["txtAnnual_Salary_Increase_Rate"]:0.05;

  $url="RetirementGetChart.php?";

  $url .= "Monthly_savings=" . $monthly_savings;

  $url .= "&Annual_Investment_growth_rate=" . $annual_investment_growth_rate;

  $url .= "&Annual_Salary_Increase_Rate=" . $annual_salary_increase_rate;

 

  function writeError($val)

  {

    echo "<br/><span style=\"color: red\">" . $val . "</span>";

  }

?>

 

<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN"

"http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">

 

<html xmlns="http://www.w3.org/1999/xhtml">

 

<head>

      <title>Retirement</title>

      <style type="text/css">

            TD, INPUT, SELECT

            {

            font-family: Arial;

            font-size: 10pt;

            }

 

            TABLE#HTInput, #HTOutput

            {

            border-top:solid 1px #C0C0C0;

            border-left:solid 1px #C0C0C0;

            }

 

            TABLE#HTInput TD, TABLE#HTOutput TD

            {

            border-bottom:solid 1px #C0C0C0;

            border-right:solid 1px #C0C0C0;

            }

 

            TABLE#HTOutput TD

            {

            background-color:#CCCCFF;

            }

      </style>

</head>

 

<body>

  <form name="form1" id="form1" action="RetirementWithChart.php" method="post">

            <table id="HTInput" border="0" cellpadding="0" cellspacing="0" width="600">

                  <tr>

                        <td style="width: 328px">Monthly savings:</td>

                        <td>

                          <input name="txtMonthly_Savings" value='<?php echo $monthly_savings ?>' type="text" />

                          <?php

                            if (!$monthly_savings)

                              writeError("Montly savings must be in between 1 and 100000");

                          ?>

                        </td>

                  </tr>

                  <tr>

                        <td style="width: 328px">Annual Investment growth rate (between 0-1):</td>

                        <td>

                          <input name="txtAnnual_Investment_Growth_Rate" value="<?php echo $annual_investment_growth_rate ?>" type="text" />

                        </td>

                  </tr>

                  <tr>

                        <td style="width: 328px">Annual Salary Increase Rate (between 0-1):</td>

                        <td>

                          <input name="txtAnnual_Salary_Increase_Rate" value="<?php echo $annual_salary_increase_rate ?>" type="text" />

                        </td>

                  </tr>

                  <tr>

                        <td style="width: 328px">&nbsp;</td>

                        <td>&nbsp;</td>

                  </tr>

                  <tr>

                        <td style="width: 328px">&nbsp;</td>

                        <td><input name="btnCalculate" type="submit" value="Calculate" /></td>

                  </tr>

            </table>

            <img src="<?php echo $url ?>">

  </form>

 

</body>

 

</html>