title: On hitting refresh of the web page , Button1_Click event is fired again
body: <p>I have a simple webform which have few text fields,leabels and Submit button. When I click on Submit button then button1 event is fired and data is Submitted.</p>
  
  <p>But what worries me is , when I refresh the page after submitting data immediately  and then I get the following errror:</p>
  
  <p><img src="https://i.stack.imgur.com/rGRkm.jpg" alt="enter image description here"></p>
  
  <p>And when I see the database to check the entry there there exist a duplicate entry.</p>
  
  <p>I don't understand why the button click even is being fired even when I hit refresh and there is no way I clicked on Button1.</p>
  
  <p>And how do I avoid this from happening.</p>