javascript change selected option code example

Example 1: javascript select change selected

const options = Array.from(select.options);
options.forEach((option, i) => {
  if (option.value === use_id) select.selectedIndex = i;
});

Example 2: get index of selected option javascript

$("#sel").attr("selectedIndex")
// or
$("#sel")[0].selectedIndex
//or
$(this).prop('selectedIndex')

Example 3: javascript set select option

document.getElementById("mySelectID").value="my_value";
//note: setting value in html directly does not work <select value="my_value">