blocks|key|2770561|text|我很确定像var+array+=+[];+这样的数组是对象数组。根据Javascript的工作方式，您不必担心空指针异常，所以只需定义数组，就像使用空对象初始化数组一样，看看它是否有效。|type|unstyled|depth|inlineStyleRanges|offset|length|style|CODE|BOLD|entityRanges|data|2770562|entityMap^0|5|F|L|6|0^^$0|@$1|2|3|4|5|6|7|I|8|@$9|J|A|K|B|C]|$9|L|A|M|B|D]]|E|@]|F|$]]|$1|G|3|-4|5|6|7|N|8|@]|E|@]|F|$]]]|H|$]]

I'm pretty sure that an array like <code>var array = [];</code> is an array of Objects. Based on how Javascript works, you never have to worry about null-pointer exceptions, so just define the array and act like you initialized it with the empty objects and see if it works

blocks|key|2770577|text|一般来说，写作的方式|type|unstyled|depth|inlineStyleRanges|entityRanges|data|2770578|var+array+=+[];
array[0]+=+{};
array[1]+=+{};
//........
//........|code-block|syntax|javascript|2770579|在没有大量复制的情况下，正确的方式是使用for循环：|2770580|var+array+=+[];
for(var+i=0;+i<10;+i%2B%2B){
++array[i]+=+{};
}|2770581|entityMap^0|0|0|0|0^^$0|@$1|2|3|4|5|6|7|M|8|@]|9|@]|A|$]]|$1|B|3|C|5|D|7|N|8|@]|9|@]|A|$E|F]]|$1|G|3|H|5|6|7|O|8|@]|9|@]|A|$]]|$1|I|3|J|5|D|7|P|8|@]|9|@]|A|$E|F]]|$1|K|3|-4|5|6|7|Q|8|@]|9|@]|A|$]]]|L|$]]

In general, the way to write

<pre><code>var array = [];
array[0] = {};
array[1] = {};
//........
//........
</code></pre>

in a sane manner without lots of copy paste is to use a for loop:

<pre><code>var array = [];
for(var i=0; i&lt;10; i++){
 array[i] = {};
}
</code></pre>

blocks|key|4367321|text|在数组中，以任何方式推送对象都是正确的。这完全没问题。像这样：|type|unstyled|depth|inlineStyleRanges|entityRanges|data|4367322|var+arr+=+[];
arr.push({});+//+ok
aa[1]+=+{}+//+also+ok|code-block|syntax|javascript|4367323|或者：|4367324|var+arr+=+[{},+{},+{}];+//+the+way+you+are+doing+is+also+fine|4367325|或者，如果你想通过循环来做，那也没关系。比如：|4367326|var+arr+=+[];
for(var+i=0;+i<5;+i%2B%2B){
++++arr[i]+=+{};
}|4367327|entityMap^0|0|0|0|0|0|0^^$0|@$1|2|3|4|5|6|7|Q|8|@]|9|@]|A|$]]|$1|B|3|C|5|D|7|R|8|@]|9|@]|A|$E|F]]|$1|G|3|H|5|6|7|S|8|@]|9|@]|A|$]]|$1|I|3|J|5|D|7|T|8|@]|9|@]|A|$E|F]]|$1|K|3|L|5|6|7|U|8|@]|9|@]|A|$]]|$1|M|3|N|5|D|7|V|8|@]|9|@]|A|$E|F]]|$1|O|3|-4|5|6|7|W|8|@]|9|@]|A|$]]]|P|$]]

In your array, pushing object in any way is right. That's totally ok. like:

<pre><code>var arr = [];
arr.push({}); // ok
aa[1] = {} // also ok
</code></pre>

or:

<pre><code>var arr = [{}, {}, {}]; // the way you are doing is also fine
</code></pre>

Or, if you want to do it via loop, that is also fine. Like:

<pre><code>var arr = [];
for(var i=0; i&lt;5; i++){
 arr[i] = {};
}
</code></pre>

blocks|key|4367350|text|数组可以动态增长和收缩。所以从某种角度来看，它们的长度已经不确定了。如果愿意，始终可以向其添加新的对象。|type|unstyled|depth|inlineStyleRanges|entityRanges|data|4367351|您还可以创建一个助手函数，它首先检查一个对象是否在某个位置存在，如果不存在，则创建一个新的对象。|4367352|您提到了array[2].value+=+'foo'作为一个例子。下面是一个可以使用的助手函数：|offset|length|style|CODE|4367353|function+getObjectAtIndex(arr,+index)+{
++++return+arr[index]+%7C%7C+(arr[index]+=+{});
}|code-block|syntax|javascript|4367354|然后，与其编写array[2].value+=+'foo'，不如编写：|4367355|getObjectAtIndex(array,+2).value+=+'foo'|4367356|entityMap^0|0|0|4|M|0|0|7|M|0|0^^$0|@$1|2|3|4|5|6|7|U|8|@]|9|@]|A|$]]|$1|B|3|C|5|6|7|V|8|@]|9|@]|A|$]]|$1|D|3|E|5|6|7|W|8|@$F|X|G|Y|H|I]]|9|@]|A|$]]|$1|J|3|K|5|L|7|Z|8|@]|9|@]|A|$M|N]]|$1|O|3|P|5|6|7|10|8|@$F|11|G|12|H|I]]|9|@]|A|$]]|$1|Q|3|R|5|L|7|13|8|@]|9|@]|A|$M|N]]|$1|S|3|-4|5|6|7|14|8|@]|9|@]|A|$]]]|T|$]]

Arrays can grow and shrink dynamically. So from a certain point of view, they are already of undefined length. You can always add new objects to it if you want to. 

You can also create a helper function which checks first if an object exists at a certain position and if not, creates a new one.

You mentioned <code>array[2].value = 'foo'</code> as an example. Here is a helper function that you could use:

<pre><code>function getObjectAtIndex(arr, index) {
 return arr[index] || (arr[index] = {});
}
</code></pre>

and then, instead of writing <code>array[2].value = 'foo'</code>, you'd write:

<pre><code>getObjectAtIndex(array, 2).value = 'foo'
</code></pre>

<pre><code>var array = [];

var object = {};
</code></pre>

Now, I need an array of empty objects.

<pre><code>array[0] = {};
array[1] = {};
//........
//........
</code></pre>

and 

<pre><code>var array = [{}];
</code></pre>

is obviously not right.

How to define array of (empty) objects in JS?

<pre><code>var array = [{},{},{},{},.........];
</code></pre>

Thanks.

EDIT:

The reason I need is the same reason that having an array with undefined length is useful, and mathematically natural in some cases.

I need object wrappers, and for initialization, it's just an empty object, like some values are null or undefined in many cases.

so, I'll have

var object = {};

<code>array[0].value = 'foo', array[1].value = 'bar'.....</code>

However, I do need multiple object wrappers, and the number is not pre-determined, so consequently, I need an arrays of the objects.

So, I am sorry, I modify my Question title

JavaScript How to define an array of undefined length of empty objects?

JavaScript How to define an array of undefined length of empty objects?

翻译质量差，导致语言生硬或混乱。

没有提供实际的解决方法或示例。

解答不清晰，无法理解或解决问题。

页面排版不美观，阅读体验差。

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问JavaScript如何定义未定义的空对象长度数组？
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