title: Fix PHP Notice: 'Undefined index' on Wordpress
body: <p>I'm trying to fix the Undefined index PHP notice on a wordpress site.</p>
  
  <p>At the moment this is what I got:</p>
  
  <pre><code>    &lt;?php if($_SESSION['currency-select'] == "a") echo 'selected="selected"';?&gt;
  </code></pre>
  
  <p>I tried to write this way but then the site goes down:</p>
  
  <pre><code>    &lt;?php if(isset($_SESSION['currency-select'] == "a")) echo 'selected="selected"';?&gt;
  </code></pre>
  
  <p>Also, I have a query which is also without isset and i'm trying to fix it:</p>
  
  <pre><code>                    if($_SESSION['currency-select'] == 'b') {
  
                  if($_GET['pricing'] == '1') {
  
                      $args['meta_query'][] = array(
  
                          'key' =&gt; 'price',
  
                          'value' =&gt; array( '0', '250' ),
  
                          'compare' =&gt; 'BETWEEN',
  
                          'type' =&gt; 'numeric'
  
                      );
  
                  }
  </code></pre>
  
  <p>I tried to write:</p>
  
  <pre><code>      if(isset($_GET['pricing'] == '1')) {
        if($_GET['pricing']) {
  </code></pre>
  
  <p>but it doesn't work as well.</p>
  
  <p>Thanks for your support!</p>