Question

我想显示“附件”部分的表格格式。我有查询和结果数据。两者都有attachmentTypeId的共同列。我想基于id显示附件类别描述。在ng-bind我试过尝试，但是没有用。

我在ng-bind中使用了一个函数，希望这种方法是错误的，期望该方法的替代方法。

attachmentLookup包含attachmentDesc，attachmentTypeId

  $scope.attachmentLookup = [{
    "attachmentDesc": "Category One",
    "attachmentTypeId": "1"
  }, {
    "attachmentDesc": "Category Two",
    "attachmentTypeId": "2"
  }, {
    "attachmentDesc": "Category Three",
    "attachmentTypeId": "3"
  }, {
    "attachmentDesc": "Category Four",
    "attachmentTypeId": "4"
  }, {
    "attachmentDesc": "Category Five",
    "attachmentTypeId": "5"
  }];

数据库中的attachmentDetails数据为，

  $scope.attachmentDetails = [{
    "attachmentId": "001",
    "fileName": "File Name 001",
    "attachmentTypeId": "1"
  }, {
    "attachmentId": "003",
    "fileName": "File Name 003",
    "attachmentTypeId": "2"
  }, {
    "attachmentId": "005",
    "fileName": "File Name 005",
    "attachmentTypeId": "3"
  }, {
    "attachmentId": "007",
    "fileName": "File Name 007",
    "attachmentTypeId": "1"
  }, {
    "attachmentId": "009",
    "fileName": "File Name 009",
    "attachmentTypeId": "2"
  }, {
    "attachmentId": "011",
    "fileName": "File Name 011",
    "attachmentTypeId": "3"
  }];

HTML代码为

<table>
  <thead>
    <tr>
      <th>File Name</th>
      <th>|</th>
      <th>Category</th>
    </tr>
  </thead>
  <tbody>
    <tr ng-repeat="attachment in attachmentDetails">
      <td> <span ng-bind="attachment.fileName"></span>
      </td>
      <td>|</td>
      <td> <span ng-bind="getCatgoryName(attachment.attachmentTypeId)"></span>
      </td>
    </tr>
  </tbody>
</table>

来自控制器的getCatgoryName代码是，

$scope.getCatgoryName = function (attachmentTypeId) {
    angular.forEach($scope.attachmentLookup, function (attachemnt) {
        if (attachemnt.attachmentTypeId === attachmentTypeId)
            return attachemnt.attachmentDesc;
    });
};

Sample Plunker：http://plnkr.co/edit/dZy5gW4q9CxWF2NszXYc

Answer 1

括号被检查脏，因此将为每个$digest调用该函数。

这个ng-bind是一个指令，它将使用观察者传递给ng-bind的内容。

因此，ng-bind仅在传递的变量或值确实发生变化时才适用。

使用函数，您不会传递变量，因此不会为每个$digest触发。

因此，最好使用带有函数调用的括号。

我在这里更新了plunker：http://plnkr.co/edit/LHC2IZ0Qk9LOOYsjrjaf?p=preview

我在这里更改了HTML：

<tr ng-repeat="a in attachmentDetails">
    <td> <span>{{a.fileName}}</span></td>
    <td>|</td>
    <td> {{ getCatgoryName(a.attachmentTypeId) }}</td>
</tr>

该功能也已被修改：

  $scope.getCatgoryName = function(attachmentTypeId) {
    var desc = "";
    angular.forEach($scope.attachmentLookup, function(attachemnt) {
      if (parseInt(attachemnt.attachmentTypeId) == attachmentTypeId)
        desc = attachemnt.attachmentDesc;
    });

    return desc;
  };

Answer 2

另一种做同样事情的方法如下：

<tr ng-repeat="delivery in deliveries">
<td>{{delivery.pickup}}</td>
<td>{{delivery.destination}}</td>
<td>{{getVehicleDescription(delivery) || (delivery.isVehicleDescription ? delivery.modelType : delivery.vehicleType)}}</td></tr>

控制器功能也以这种方式修改：

$scope.getVehicleDescription = function(delivery){
        $scope.roads.map(function(road){
            if(road.modelTypeID == delivery.vehicleType && !delivery.isVehicleDescription){
                delivery.modelType = road.modelType;
                delivery.isVehicleDescription = true;
            }
        })
    };

AngularJS ng-bind与函数

2 个答案: