这是我第一次使用下划线...我有这个简单的 json...
"categories" : [
{
"tag" : "cat1",
"active" : true,
"order" : 10,
"title" : {
"en" : "Category 1",
"pt" : "Categoria 1"
},
"children" : [
{
"tag" : "cat11",
"active" : true,
"order" : 10,
"title" : {
"en" : "Category 1.1",
"pt" : "Categoria 1.1"
}
},
{
"tag" : "cat12",
"active" : true,
"order" : 20,
"title" : {
"en" : "Category 1.2",
"pt" : "Categoria 1.2"
}
}
]
},
{
"tag" : "cat2",
"active" : true,
"order" : 10,
"title" : {
"en" : "Category 2",
"pt" : "Categoria 2"
},
"children" : [
{
"tag" : "cat21",
"active" : true,
"order" : 10,
"title" : {
"en" : "Category 2.1",
"pt" : "Categoria 2.1"
}
},
{
"tag" : "cat22",
"active" : true,
"order" : 20,
"title" : {
"en" : "Category 2.2",
"pt" : "Categoria 2.2"
}
}
]
},
{
"tag" : "cat3",
"active" : true,
"order" : 10,
"title" : {
"en" : "Category 3",
"pt" : "Categoria 3"
},
"children" : [
{
"tag" : "cat31",
"active" : true,
"order" : 10,
"title" : {
"en" : "Category 3.1",
"pt" : "Categoria 3.1"
}
},
{
"tag" : "cat32",
"active" : true,
"order" : 20,
"title" : {
"en" : "Category 3.2",
"pt" : "Categoria 3.2"
}
}
]
},
{
"tag" : "cat4",
"active" : true,
"order" : 10,
"title" : {
"en" : "Category 4",
"pt" : "Categoria 4"
},
"children" : [
{
"tag" : "cat41",
"active" : true,
"order" : 10,
"title" : {
"en" : "Category 4.1",
"pt" : "Categoria 4.1"
}
},
{
"tag" : "cat42",
"active" : true,
"order" : 20,
"title" : {
"en" : "Category 4.2",
"pt" : "Categoria 4.2"
}
}
]
}
]
您可以在多个地方看到我的 TAG key 。我需要根据标签标准获取整个树。我使用 find、filter、where 和 findWhere，并且一直得到相同的结果:
var find = _.find($rootScope.webshop.categories, {tag: 'cat1'});
这有效!
但如果我尝试...
var find = _.find($rootScope.webshop.categories, {tag: 'cat11'});
没有结果:( 即使使用 _.where 或 ._filter 或 ._findWhere。 - 结果总是相同的。 有人可以帮助 Underscore 初学者做一些可能很简单的事情吗？!
我!
最佳答案
_.find 不会递归，您必须构建自己的解决方案。像这样的事情:
_.findIn = function() {
var args = Array.prototype.slice.call(arguments, 0);
var childrenProp = args[0];
var result = _.find.apply(_, args.slice(1));
if (result !== void(8)) return result;
var arr = args[1];
for (var i = 0, l = arr.length; i < l; i++) {
args[1] = arr[i][childrenProp];
var result = _.findIn.apply(_, args);
if (result !== void(8)) return result;
}
return void(8);
}
_.findIn('children', categories, {tag: 'cat11'})
categories = [
{
"tag" : "cat1",
"active" : true,
"order" : 10,
"title" : {
"en" : "Category 1",
"pt" : "Categoria 1"
},
"children" : [
{
"tag" : "cat11",
"active" : true,
"order" : 10,
"title" : {
"en" : "Category 1.1",
"pt" : "Categoria 1.1"
}
},
{
"tag" : "cat12",
"active" : true,
"order" : 20,
"title" : {
"en" : "Category 1.2",
"pt" : "Categoria 1.2"
}
}
]
},
{
"tag" : "cat2",
"active" : true,
"order" : 10,
"title" : {
"en" : "Category 2",
"pt" : "Categoria 2"
},
"children" : [
{
"tag" : "cat21",
"active" : true,
"order" : 10,
"title" : {
"en" : "Category 2.1",
"pt" : "Categoria 2.1"
}
},
{
"tag" : "cat22",
"active" : true,
"order" : 20,
"title" : {
"en" : "Category 2.2",
"pt" : "Categoria 2.2"
}
}
]
},
{
"tag" : "cat3",
"active" : true,
"order" : 10,
"title" : {
"en" : "Category 3",
"pt" : "Categoria 3"
},
"children" : [
{
"tag" : "cat31",
"active" : true,
"order" : 10,
"title" : {
"en" : "Category 3.1",
"pt" : "Categoria 3.1"
}
},
{
"tag" : "cat32",
"active" : true,
"order" : 20,
"title" : {
"en" : "Category 3.2",
"pt" : "Categoria 3.2"
}
}
]
},
{
"tag" : "cat4",
"active" : true,
"order" : 10,
"title" : {
"en" : "Category 4",
"pt" : "Categoria 4"
},
"children" : [
{
"tag" : "cat41",
"active" : true,
"order" : 10,
"title" : {
"en" : "Category 4.1",
"pt" : "Categoria 4.1"
}
},
{
"tag" : "cat42",
"active" : true,
"order" : 20,
"title" : {
"en" : "Category 4.2",
"pt" : "Categoria 4.2"
}
}
]
}
]
_.findIn = function() {
var args = Array.prototype.slice.call(arguments, 0);
var childrenProp = args[0];
var result = _.find.apply(_, args.slice(1));
if (result !== void(8)) return result;
var arr = args[1];
for (var i = 0, l = arr.length; i < l; i++) {
args[1] = arr[i][childrenProp];
var result = _.findIn.apply(_, args);
if (result !== void(8)) return result;
}
return void(8);
}
document.write(JSON.stringify(_.findIn('children', categories, {tag: 'cat11'})));<script src="//cdnjs.cloudflare.com/ajax/libs/underscore.js/1.7.0/underscore-min.js"></script>关于javascript - 下划线 - 基于值定位节点，我们在Stack Overflow上找到一个类似的问题： https://stackoverflow.com/questions/27179905/