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iterating over an array and selecting a select option that matches

So I am using jQuery...

I have a json object that looks like this

    access_list: {},
    role_list: {
      sys admin: true,
      system administrator: true
  site_list: {
    0: {
      id: 0,
      name: "All Sites",
      code: "NEEDS_TO_BE_SET"
    3681: {
      id: 3681,
      name: "Mohave, AZ",
      code: "MAZ"
    3682: {
      id: 3682,
      name: "Salt Lake, UT",
      code: "SLUT"
  username: "bsmith",
  first_name: "Bob",
  last_name: "Smith",
  organization: "Acme",
  email_addr: "bsmith@acme.com",
  contact_info: "",
  disabled: false,
  password_dttm: "2015-03-10 15:50:01.740397",
  role_level: 0

Then I have a select box (multiselect) called #roleBox that has a list of options. I need to iterate over the JSON object for role_list and for each key that matches an option in the select I need to make that option selected.

I have a second select box (multiselect) called #siteBox I have to iterate over the JSON's site_list and if a key is 0 select only the first option in #siteBox else find the options in #siteBox that match the keys in sitelist and make those options selected.

This is driving me nuts hopefully Andrew Chalkley knows this one.

1 Answer

Alec Plummer
Alec Plummer
15,181 Points

Alright, so...this one is a little confusing lol. Hope some of this helps and I'm not completely missing the mark here!

The html..

<select id="roleBox">

I'm using data as my mock json file. What I'm doing here is looping first through the data.role_list object then looping through all of the #roleBox options. If there is a match, the #roleBox changes its current selected option to the matching value in your role_list object.

var data = {
    role_list: {
        sysAdmin: true,
        systemAdmin: true

$.each(data.role_list, function(i, item) {
    $('#roleBox > option').each(function() {
        if ($(this).val() === 'true') {
            $(this).prop('selected', true);

A similar approach will work for your second part of the question as well, just change what you're looping through and exit the loop when you find a match

$.each(data.site_list, function(i, item) {
    $('#siteBox > option').each(function() {
        if ($(this).val() === 0) {
            $(this).prop('selected', true);

Right on the money! I did have to make a small change on the second (site iterator) so that is === 0 was false then loop over each other block (non 0 block)

Alec Plummer
Alec Plummer
15,181 Points

Awesome! Glad I could help.