From 3990173db1207767139e63d33783beafada57007 Mon Sep 17 00:00:00 2001
From: oleibman <10341515+oleibman@users.noreply.github.com>
Date: Thu, 5 Sep 2024 10:27:28 -0700
Subject: [PATCH] Validate POST Input in Sample 45

Errors will result if inputs are not numeric.
---
 samples/Basic4/45_Quadratic_equation_solver.php | 6 ++++--
 1 file changed, 4 insertions(+), 2 deletions(-)

diff --git a/samples/Basic4/45_Quadratic_equation_solver.php b/samples/Basic4/45_Quadratic_equation_solver.php
index 30aabf60f5..d681a21092 100644
--- a/samples/Basic4/45_Quadratic_equation_solver.php
+++ b/samples/Basic4/45_Quadratic_equation_solver.php
@@ -14,7 +14,7 @@
 }
 ?>
 <form action="45_Quadratic_equation_solver.php" method="POST">
-    Enter the coefficients for the Ax<sup>2</sup> + Bx + C = 0
+    Enter the coefficients for Ax<sup>2</sup> + Bx + C = 0
     <table border="0" cellpadding="0" cellspacing="0">
         <tr>
             <td>
@@ -47,7 +47,9 @@
 <?php
 /**     If the user has submitted the form, then we need to execute a calculation * */
 if (isset($_POST['submit'])) {
-    if ($_POST['A'] == 0) {
+    if (!is_numeric($_POST['A']) || !is_numeric($_POST['B']) || !is_numeric($_POST['C'])) { // validate input
+        $helper->log('Non-numeric input');
+    } elseif ($_POST['A'] == 0) {
         $helper->log('The equation is not quadratic');
     } else {
         // Calculate and Display the results