How to retrieve all choice field values using ecmascript – SharePoint 2010

I had a requirenment to get all the choice values in one of my choice colums in a list, and I want to add these values into a html dropdown on page load.

Just copy and paste the bellow code inside script tag and change ListName, ColumnName and Dropdown Id :

• window.onload = retrieveListItems;
  var deptChoiceField;

• function retrieveListItems() {
          varclientContext = SP.ClientContext.get_current();
          var webSite = clientContext.get_web();
          var lists = webSite.get_lists();
          var oList = lists.getByTitle(“ListName“);
  deptChoiceField = clientContext.castTo(oList.get_fields().getByInternalNameOrTitle(“ColumnName“),SP.FieldChoice);
  clientContext.load(deptChoiceField);
  clientContext.executeQueryAsync(
  Function.createDelegate(this, this.fillDropDown),
  Function.createDelegate(this, this.onListDataLoadQueryFailed));
  }

• function onListDataLoadQueryFailed(sender, args) {
  alert(‘Request failed. ‘ + args.get_message() + ‘\n’ + args.get_stackTrace());
  }

• function fillDropDown() {
  var choices = deptChoiceField.get_choices();
       var ddlCategory = document.getElementById(‘ddl‘);
       if (ddlCategory != null)
  {
              for (var i = 0; i < choices.length; i++)
  {
                    var theOption = new Option;
  theOption.text = choices[i];
  ddlCategory.options[i] = theOption;
  }
  }
  }