title: Undefined index with $_POST function
body: <p>So I Basically copied the following code, execpt renaming columns names.</p>
  
  <p>The form is folowing:</p>
  
  <pre><code>&lt;table align="left" width="30%" border="0" &gt;
  &lt;form action="company_edit_php.php" method="post"&gt;
  &lt;tr&gt;&lt;td align="center" bgcolor="#ECE6E6"&gt;Location: &lt;td align="center"&gt; &lt;input type="text" value="&lt;?php echo $row['Location']?&gt;"/&gt;&lt;br&gt;&lt;/td&gt;&lt;/tr&gt;
  &lt;tr&gt;&lt;td align="center" bgcolor="#ECE6E6"&gt;User: &lt;td align="center"&gt;  &lt;input type="text" value="&lt;?php  echo $row['User']?&gt;"/&gt;&lt;br&gt;&lt;/td&gt;&lt;/tr&gt;
  &lt;tr&gt;&lt;td align="center" bgcolor="#ECE6E6"&gt;Telephone: &lt;td align="center"&gt;  &lt;input type="text" value="&lt;?php echo $row['Telephone']?&gt;"/&gt;&lt;br&gt;&lt;/td&gt;&lt;/tr&gt;
  &lt;tr&gt;&lt;td align="center" bgcolor="#ECE6E6"&gt;Email: &lt;td align="center"&gt;  &lt;input type="text" value="&lt;?php echo $row['Email']?&gt;"/&gt;&lt;br&gt;&lt;/td&gt;&lt;/tr&gt;
  &lt;td&gt; &lt;input type="submit" value="Change" /&gt;&lt;/td&gt;&lt;/tr&gt;
  </code></pre>
  
  <p>And PHP code:</p>
  
  <pre><code>&lt;?php
  $con = mysql_connect("localhost","username","password");
  $id = isset($_GET['id']) ? (int)$_GET['id']: 1;
  mysql_select_db("Database", $con);
  
  if (isset($_POST['Location'])) {
      echo $_POST['Location'];
   } else {
      echo 'empty';
   } 
  
  $Location = $_POST['Location'];
  </code></pre>
  
  <p>Result of this code is Undefined index: Location and from if statement i get "empty".
  Why this same code work for another page? What should I do now?</p>
  
  <p>Thank you for your efforts</p>