How to post a select result without a submit button using Jquery or Javascript?

Dear Experts,
How can I post below select options results to action page without a submit button?
I'm using PHP.

I think I should use JQeuery to that but I don't know how to that?
Could you please help me?

<form name="form1" method="post" action="actionpage.php">
  
<select class="form-control" name="bolge" style="max-width:350px;">
    <option value="">Select?</option>
	<option value="1">1</option>
     <option value="2">2</option>
</select>

</form>

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