title: PHP: read value of input field
body: <p>I have a very basic question about PHP. So, there is <code>index.php</code> that includes a form. This form contains input field <code>field1</code>:</p>
  
  <p><strong>index.php</strong></p>
  
  <pre><code>    &lt;div id="container1"&gt;
      &lt;form name="optform" method="post" action="processing.php"&gt;
                  &lt;div class = "box"&gt;
                      &lt;label for="field1"&gt;&lt;span&gt;Bla bla bla:&lt;/span&gt;&lt;/label&gt;
                      &lt;input type="text" class="input-text" value="5" size="11" maxlength="11" name="field1" id="field1"&gt;
                  &lt;/div&gt;
                  &lt;br/&gt;
              &lt;div class="buttons"&gt;
                  &lt;a href="" class="regular" onclick="click_function();return false;"&gt;Run&lt;/a&gt;
              &lt;/div&gt;
      &lt;/form&gt;
      &lt;/div&gt;
  
      &lt;div id="container2"&gt;
  
      &lt;/div&gt;
  
      &lt;script language="javascript"&gt;
      function click_function() {
           $('#container2').load('processing.php');
      }
      &lt;/script&gt;
  </code></pre>
  
  <p>I need to use the value from <code>field1</code> in another PHP file called as <code>processing.php</code>. So, how can I read this value from <code>processing.php</code>? Should I do something like this in <code>processing.php</code>:?</p>
  
  <p><strong>processing.php</strong></p>
  
  <pre><code>$field1value = $_POST["field1"];
  </code></pre>