javascript 如何映射多维数组（使用下划线）？
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How to map a multidimensional array (using Underscore)?
提问by GloryOfThe80s
I have a large, multidimensional array of JSON objects that I want to map through (using Underscore). For example:
我有一个大型的多维 JSON 对象数组，我想通过这些对象进行映射（使用 Underscore）。例如：
var dummyData = [
[{title: 'a'},{title : 'b'}],
[{title: 'a'},{title : 'b'}],
[{title: 'a'},{title : 'b'}],
[{title: 'a'},{title : 'b'}]
];
For the function body of the _.map, I want to run each JSON object through a Backbone Model constructor. So far, I've tried something like this to accomplish this:
对于 的函数体_.map，我想通过 Backbone Model 构造函数运行每个 JSON 对象。到目前为止，我已经尝试过这样的事情来实现这一点：
_.map(dummyData, function() {
_.each(dummyData, function(el, i) {
// run each object through the constructor
}
})
I'm getting caught up on the _.each, though - since dummyDataisn't actually the 'list' that I want to loop through.
不过，我正在关注_.each，因为dummyData实际上并不是我想要遍历的“列表”。
Or am I thinking about this wrong altogether?
还是我完全在考虑这个错误？
回答by thefourtheye
Iterate over the elements of dummyData, with _.maplike this
迭代 的元素dummyData，_.map像这样
_.map(dummyData, function(currentDummyData) {
return _.map(currentDummyData, function(el, i) {
// run each object through the constructor
})
});
dummyDatais an Array of Arrays. When you use _.mapwith that, it picks up each array in the array of arrays and passes to the function, which we accept with function(currentDummyData) {..}.
dummyData是一个数组数组。当你使用_.map它时，它会选择数组数组中的每个数组并传递给我们接受的函数function(currentDummyData) {..}。
Inside that function, we again _.mapthat array, because it is still an array. So, we iterate that to get individual elements and pass them to the function function(el, i) {..}, where new Backbone models are created.
在该函数内部，我们再次使用_.map该数组，因为它仍然是一个数组。因此，我们迭代它以获取单个元素并将它们传递给函数function(el, i) {..}，在那里创建新的 Backbone 模型。
Note:You have to return the result of _.map, like in the answer. Because, _.mapexpects the function called to return an object and all the returned objects will be gathered to create a new array.
注意：您必须返回 的结果_.map，就像在答案中一样。因为，_.map期望被调用的函数返回一个对象，所有返回的对象将被收集起来以创建一个新数组。
For example,
例如，
console.log(_.map(dummyData, function(currentDummyData) {
return _.map(currentDummyData, function(el, i) {
return {title: el.title + el.title};
})
}));
will produce
会产生
[ [ { title: 'aa' }, { title: 'bb' } ],
[ { title: 'aa' }, { title: 'bb' } ],
[ { title: 'aa' }, { title: 'bb' } ],
[ { title: 'aa' }, { title: 'bb' } ] ]
