app.filter("highlight", function($sce, $log){
  var fn = function(text, search){
    $log.info("text: " + text);
    $log.info("search: " + search);
    if (!search) {
      return $sce.trustAsHtml(text);
    }
    text = encodeURIComponent(text);
    search = encodeURIComponent(search);
    var regex = new RegExp(search, 'gi')
    var result = text.replace(regex, '<span class="highlightedTextStyle">$&</span>');
    result = decodeURIComponent(result);
    $log.info("result: " + result );
    return $sce.trustAsHtml(result);
  };
  return fn;
});

<div ng-controller="search">
      <div>
        <input type="text" ng-model="notify.search" value=""/>
      </div>
      <!--text内容会高亮显示搜索关键字-->
      <div ng-bind-html="text | highlight:notify.search">
      </div>
</div>

app.controller("search", function($scope){
  $scope.text = "hello, world. hello, world. hello, world. this is filter example.";
  $scope.notify.search = "";
})