Set Select Option 'selected' In A Modal Bootstrap

I have a select field and I have to select one of those options with jQuery. I have this method, and it works for me anywhere, except in a modal. When I open my target page, it ope

Solution 1:

you should place your script before the html code of the modal as below.

<script>
    var echelle= document.getElementById('echelle');
    echelle.value = 'trimestrielle';
</script>

<div class='modal small fade' id="myModal2" tabindex="-1" role="dialog" aria-labelledby="myModalLabel" aria-hidden="true">
    <div class="modal-dialog">
        <div class="modal-content">
            <form method="post" action="UpdateMPrev" >
                <select id="echelle"  name="echelle" class="form-control">                     
                    <option value="mensuelle"> Mensuelle</option>  
                    <option value="trimestrielle">Trimestrielle</option> 
                    <option value="semestrielle" > Semestrielle</option> 
                    <option value="annuelle" > Annuelle</option> 
                    <option value="aucun"> Aucun</option> 
                </select>
                <input type="submit"/>
            </form>
        </div>
    </div>
</div>