var match = optionsExp.match(NG_OPTIONS_REGEXP);
if (!(match)) {
console.log('ng-options 表达式有误')
}
var valueName = match[5] || match[7];
var keyName = match[6];
var displayFn = $parse(match[2]);
var keyFn = $parse(match[1]);
var valuesFn = $parse(match[8]);

var labelArray = [],idArray = [],optionValues = [];
scope.$watch(match[8],function(newValue,oldValue) {
if (newValue && newValue.length > 0) {
optionValues = valuesFn(scope) || [];
labelArray = [];
idArray = []
for (var index = 0,l = optionValues.length; index < l; index++) {
var it = optionValues[index];
if (match[2] && match[1]) {
var localIt = {};
localIt[valueName] = it;
var label = displayFn(scope,localIt);
var dataId = keyFn(scope,localIt);
labelArray.push(label);
idArray.push(dataId);
}
}

 scope.options = {
  'optionValues': optionValues,'labelArray': labelArray,'idArray': idArray
 }
}

});
}
return {
restrict: 'A',require: ['ngModel'],priority: 100,replace: false,scope: true,template: '<div class="chose-container">' +
'<div class="chose-single"><span class="j-view"><i class="glyphicon glyphicon-remove">' +
'<div class="chose-drop chose-hide j-drop">' +
'<div class="chose-search">' +
'<input class="j-key" type="text" autocomplete="off">' +
'' +
'<ul class="chose-result">' +
// '

 var tmplNode = $(this.template).first();

 var modelName = attr.ngModel,name = attr.name? attr.name:('def'+Date.now());
 tmplNode.attr('id',name + '_chosecontianer');

 $animate.enter(tmplNode,element.parent(),element);
},post: function selectSearchPostLink(scope,ctrls) {
 var choseNode = element.next(); //$('#'+attr.name +'_chosecontianer');
 choseNode.addClass(attr.class);
 element.addClass('chose-hide');
 // 当前选中项
 var ngModelCtrl = ctrls[0];
 if (!ngModelCtrl || !attr.name) return;

 par<a href="https://www.jb51.cc/tag/SEO/" title="SEO">SEO</a>ptions(attr.ngOptions,scope);
 var rs = {};

 function setView() {
  var currentKey = ngModelCtrl.$modelValue;
  if (isNaN(currentKey) || !currentKey) {
   currentKey = '';
   choseNode.find('.j-view:first').text('请选择');
   choseNode.find('i').addClass('chose-hide');
  }
  if ((currentKey + '').length > 0) {
   for (var i = 0,l = rs.idArray.length; i < l; i++) {
    if (rs.idArray[i] == currentKey) {
     choseNode.find('.j-view:first').text(rs.labelArray[i]);
     choseNode.find('i').removeClass('chose-hide');
     break;
    }
   }
  }
 }

 function setViewAndData() {
  if (!scope.options) {
   return;
  }
  rs = scope.options;
  setView();
 }
 scope.$watchCollection('options',setViewAndData);
 scope.$watch(attr.ngModel,setView);


 function getListNodes(value) {
  var nodes = [];
  value = $.trim(value);
  for (var i = 0,l = rs.labelArray.length; i < l; i++) {
   if (rs.labelArray[i].indexOf(value) > -1) {
    nodes.push($('<li>').data('id',rs.idArray[i]).text(rs.labelArray[i]))
   }
  }
  return nodes;

 }
 choseNode.on('keyup','.j-key',function() {
  // <a href="https://www.jb51.cc/tag/sousuo/" target="_blank" class="keywords">搜索</a>输入框keyup，重新筛选列表
  var value = $(this).val();
  choseNode.find('ul:first').empty().append(getListNodes(value));
  return false;
 }).on('click',function() {
  choseNode.find('.j-drop').removeClass('chose-hide');
  if (choseNode.find('.j-view:first').text() != '请选择') {
   choseNode.find('i').removeClass('chose-hide');
  }
  choseNode.find('ul:first').empty().append(getListNodes(choseNode.find('.j-key').val()));
  return false;
 }).on('click','ul>li',function() {
  var _this = $(this);
  ngModelCtrl.$setViewValue(_this.data('id'));
  ngModelCtrl.$render();
  choseNode.find('.j-drop').addClass('chose-hide');
  return false;

 }).on('click','i',function() {
  ngModelCtrl.$setViewValue('');
  ngModelCtrl.$render();
  choseNode.find('.j-view:first').text('请选择');
  return false;

 });
 $(document).on("click",function() {
  $('.j-drop').addClass('chose-hide');
  choseNode.find('i').addClass('chose-hide');
  return false;
 });

}

}
};
})

1.2 css代码(用less写的，以下是编译后的)

1.3 使用及效果