title: form submit only one time
body: <blockquote>
    <p><strong>Possible Duplicate:</strong><br>
    <a href="https://stackoverflow.com/questions/4615813/preventing-duplicate-form-submissions">Preventing duplicate form submissions</a>  </p>
  </blockquote>
  
  
  
  <p>I set a condition that is </p>
  
  <pre><code>if(isset($_POST)){
      //do some action
  }
  </code></pre>
  
  <p>For the first time the condition is checked, it works fine but if the user refreshes the page it does the action 2nd time. How should I check?</p>