Add exams from exam100 to exam150

exam135/loginform.inc.php

@@ -0,0 +1,37 @@
+<?php
+
+
+
+if (isset($_POST['username']) && isset($_POST['password'])) {
+    $username = $_POST['username'];
+    $password = $_POST['password'];
+    $password_hash = md5($password);
+
+    if (!empty($username) && !empty($password)) {
+        $query = "SELECT `id` FROM `users` WHERE `username` ='" . mysqli_real_escape_string($con, $username) .
+                 "' AND `password` = '" .mysqli_real_escape_string($con, $password_hash )."'";
+        if ($query_run = mysqli_query($con, $query)) {
+            $query_num_rows = mysqli_num_rows($query_run);
+            if ($query_num_rows == 0) {
+                echo 'invalid username/password combination';
+            } else if ($query_num_rows == 1) {
+                //treba nam $user_id
+                $row = mysqli_fetch_assoc($query_run);
+                $user_id = $row['id'];
+
+                $_SESSION['user_id'] = $user_id;
+                header('Location: index.php');
+            }
+        } else {
+        }
+    } else {
+        echo 'You must suply username or password';
+    }
+}
+
+?>
+
+<form action="<?php $current_file; ?>" method="POST">
+    Username: <input type="text" name="username"> Password: <input type="password" name="password">
+    <input type="submit" value="Submit">
+</form>