select2 去掉搜索框

main.html

<div>
  <select ui-select2='select2Options' ng-model="select2" data-placeholder="Pick a number">
    <option value=""></option>
    <option value="one">First</option>
    <option value="two">Second</option>
    <option value="three">Third</option>
  </select>
</div>

main.js

'use strict';

angular.module('select2App')
  .controller('MainCtrl', function ($scope) {
    $scope.select2Options = {
      minimumResultsForSearch: -1
    };
  });