Javascript ng repeat无法处理具有非连续数字索引的数组？
我是angular JS的新手，希望用它来处理ajax传递的json。首先，我编写了以下测试代码，以确保数据能够正确显示：Javascript ng repeat无法处理具有非连续数字索引的数组？,javascript,arrays,angularjs,Javascript,Arrays,Angularjs,我是angular JS的新手，希望用它来处理ajax传递的json。首先，我编写了以下测试代码，以确保数据能够正确显示： <head> <script src="path/to/angular.js"></script> <script> var app = angular.module('pageApp', []).config(function($interpolateProvider){
<head>
<script src="path/to/angular.js"></script>
<script>
var app = angular.module('pageApp', []).config(function($interpolateProvider){
$interpolateProvider.startSymbol('<<').endSymbol('>>');
});
</script>
</head>
<body ng-app="pageApp">
<div class="container" ng-controller="tagging">
Text input:<textarea ng-model="description" ng-change="checkTag()" required></textarea><br>
Tag found om database: <span ng-repeat="tag in tags"> << tag >> </span><br>
</div>
</body>
<script>
//$http is not used now but will be used in the actual ajax handling.
function taggingController($scope, $http) {
$scope.tags = [];
$scope.checkTag = function () {
var hardCode = [];
hardCode[1] = "one";
hardCode[3] = "three";
hardCode[5] = "five";
angular.forEach(hardCode, function(value, key) {
console.log($scope.tags[key]);
$scope.tags[key] = value
});
};
};
app.controller("tagging", taggingController);
</script>
我是否遗漏了什么，或者根本没有能力处理非连续数索引数组？问题是索引2和4中的数组中有两个未定义。为了解决这个问题，可以向索引2和索引4中添加值，或者按如下所示的索引跟踪ng repeat
<span ng-repeat="tag in tags track by $index"> << tag >> </span><br>
<span ng-repeat="tag in tags track by $index"> << tag >> </span><br>
if (isArrayLike(collection)) {
collectionKeys = collection;
trackByIdFn = trackByIdExpFn || trackByIdArrayFn;
} else {
trackByIdFn = trackByIdExpFn || trackByIdObjFn;
// if object, extract keys, in enumeration order, unsorted
collectionKeys = [];
for (var itemKey in collection) {
if (collection.hasOwnProperty(itemKey) && itemKey.charAt(0) !== '$') {
collectionKeys.push(itemKey);
}
}
}
for (index = 0; index < collectionLength; index++) {
Angular尝试确定对象是否与数组相似。一旦确定，它将基于第一个谓词设置其trackBy属性。然后它构建它的集合
if (isArrayLike(collection)) {
collectionKeys = collection;
trackByIdFn = trackByIdExpFn || trackByIdArrayFn;
} else {
trackByIdFn = trackByIdExpFn || trackByIdObjFn;
// if object, extract keys, in enumeration order, unsorted
collectionKeys = [];
for (var itemKey in collection) {
if (collection.hasOwnProperty(itemKey) && itemKey.charAt(0) !== '$') {
collectionKeys.push(itemKey);
}
}
}
for (index = 0; index < collectionLength; index++) {
您希望通过设置自己的索引来实现什么？实际数组是在通过ajax从服务器返回json时设置的，其中索引是该标记项的id。那么，如果它是
json\u编码的{3:“三”，5:“五”}[{id:3，txt:“three”}，{id:5，txt:“five”}]json_编码{3:“三”，5:“五”}[{id:3，txt:“three”}，{id:5，txt:“five”}]