i want to search dropdown list values without page refreshing. following code is working fine. when i select dropdown option it is redirect to related url value. but my requirement is when i select dropdown option and click on submit button then related url will search without page refresh.
code
<select name="menu1" id="menu1">
<option value="">Select your choice...</option>
<option value="https://free.greenhouse.com/tree/list/cucumber">Cucumber</option>
<option value="https://free.greenhouse.com/tree/list/tulasi">Tulasi</option>
<option value="https://free.greenhouse.com/tree/amond">Amond</option>
<option value="https://free.greenhouse.com/tree/list/awala">Awala</option>
</select>
</br></br>
<script type="text/javascript">
var urlmenu = document.getElementById( 'menu1' );
urlmenu.onchange = function() {
window.open( this.options[ this.selectedIndex ].value,"_self" );
};
</script>