jquery - Add new <option> to all dropdown <select> tags using javascript -

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im trying add drop down menu option "please select" top of each drop-down list on page selected default, using similar this:

window.onload = function() {     $('select option[value="psc"]').attr("selected",true); };

and im using drop-down:

window.onload = function additem(text,value) {     // create option object     var opt = document.createelement("option");     // add option object drop down/list box     document.getelementsbytagname("option").options.add(opt);     // assign text , value option object     opt.text = 'please select...';     opt.value = 'please select';   }

i'm new @ javascript, can point me in right direction compiling when page loads every drop-down list gets default selected option called "please select"

thanks in advance

modified pure javascript function function (this not affect selected option) demo jsfiddle

     window.onload = function additem(text, value) {          // drop down/list box in document         var sel = document.getelementsbytagname("select");          (var x = 0; x < sel.length; x++) {             // create option object , set it's value/text            var opt = document.createelement("option");            opt.text = 'please select...';            opt.value = 'please select';             //prepend in select box            sel[x].insertbefore(opt, sel[x].options[0])         }      }

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