blocks|key|735422|text|在JavaScript中，对象是关联的，arrays...there不是它们的单独概念。您还可以安全地使用‘’。键名中，但只能使用方括号表示法访问该值：|type|unstyled|depth|inlineStyleRanges|entityRanges|data|735423|var+foo+=+{}
foo['bar']+=+'test';
foo['baz.bin']+=+'value';

alert(foo.bar);+//+Shows+'test'
alert(foo['baz.bin']);+//+Shows+'value'|code-block|syntax|javascript|735424|如果您已经在使用它们，并且它们有效，那么您就是安全的。|735425|entityMap^0|0|0|0^^$0|@$1|2|3|4|5|6|7|K|8|@]|9|@]|A|$]]|$1|B|3|C|5|D|7|L|8|@]|9|@]|A|$E|F]]|$1|G|3|H|5|6|7|M|8|@]|9|@]|A|$]]|$1|I|3|-4|5|6|7|N|8|@]|9|@]|A|$]]]|J|$]]

In JavaScript, objects are associative arrays...there aren't separate concepts for them. You are also able to safely use '.' in a key name, but you can only access the value using the bracket notation:
<pre><code>var foo = {}
foo['bar'] = 'test';
foo['baz.bin'] = 'value';

alert(foo.bar); // Shows 'test'
alert(foo['baz.bin']); // Shows 'value'
</code></pre>
If you're using them already and they work, you're safe.

blocks|key|519039|text|没有关联数组。它只是一个物体。|type|unstyled|depth|inlineStyleRanges|entityRanges|data|519040|foo.bar;++++//+Equivalent+to...
foo["bar"];+//+Looks+like+associative+array.|code-block|syntax|javascript|519041|entityMap^0|0|0^^$0|@$1|2|3|4|5|6|7|I|8|@]|9|@]|A|$]]|$1|B|3|C|5|D|7|J|8|@]|9|@]|A|$E|F]]|$1|G|3|-4|5|6|7|K|8|@]|9|@]|A|$]]]|H|$]]

There isn't an associative array. It's just an object.
<pre><code>foo.bar; // Equivalent to...
foo[&quot;bar&quot;]; // Looks like associative array.
</code></pre>

blocks|key|735592|text|在JavaScript中，对象和数组几乎是一回事，数组具有一些神奇的功能(自动更新长度属性等)和适用于数组的原型方法。构造对象也比使用关联数组容易得多：|type|unstyled|depth|inlineStyleRanges|entityRanges|data|735593|var+obj+=+{"my.key":+"myValue"};|code-block|syntax|javascript|735594|与|735595|var+obj+=+[];
obj["my.key"]+=+"myValue";|735596|因此，千万不要为此使用数组对象，而应该只使用常规对象。|735597|一些功能：|735598|var+obj+=+{};+//+Initialized+empty+object|735599|删除键值对：|735600|delete+obj[key];|735601|检查密钥是否存在：|735602|key+in+obj;|735603|获取密钥值：|735604|obj[key];|735605|添加键值对：|735606|obj[key]+=+value;|735607|entityMap^0|0|0|0|0|0|0|0|0|0|0|0|0|0|0|0^^$0|@$1|2|3|4|5|6|7|18|8|@]|9|@]|A|$]]|$1|B|3|C|5|D|7|19|8|@]|9|@]|A|$E|F]]|$1|G|3|H|5|6|7|1A|8|@]|9|@]|A|$]]|$1|I|3|J|5|D|7|1B|8|@]|9|@]|A|$E|F]]|$1|K|3|L|5|6|7|1C|8|@]|9|@]|A|$]]|$1|M|3|N|5|6|7|1D|8|@]|9|@]|A|$]]|$1|O|3|P|5|D|7|1E|8|@]|9|@]|A|$E|F]]|$1|Q|3|R|5|6|7|1F|8|@]|9|@]|A|$]]|$1|S|3|T|5|D|7|1G|8|@]|9|@]|A|$E|F]]|$1|U|3|V|5|6|7|1H|8|@]|9|@]|A|$]]|$1|W|3|X|5|D|7|1I|8|@]|9|@]|A|$E|F]]|$1|Y|3|Z|5|6|7|1J|8|@]|9|@]|A|$]]|$1|10|3|11|5|D|7|1K|8|@]|9|@]|A|$E|F]]|$1|12|3|13|5|6|7|1L|8|@]|9|@]|A|$]]|$1|14|3|15|5|D|7|1M|8|@]|9|@]|A|$E|F]]|$1|16|3|-4|5|6|7|1N|8|@]|9|@]|A|$]]]|17|$]]

In a JavaScript, an object and array are pretty much the same thing, with an array having a bit of magical functionality (autoupdating the length property and such) and prototype methods suitable for arrays. It is also much easier to construct an object than using an associative array:
<pre><code>var obj = {&quot;my.key&quot;: &quot;myValue&quot;};
</code></pre>
vs.
<pre><code>var obj = [];
obj[&quot;my.key&quot;] = &quot;myValue&quot;;
</code></pre>
Therefore never use the array object for this, but just the regular object.
Some functionality:
<pre><code>var obj = {}; // Initialized empty object
</code></pre>
Delete a key-value pair:
<pre><code>delete obj[key];
</code></pre>
Check if a key exists:
<pre><code>key in obj;
</code></pre>
Get the key value:
<pre><code>obj[key];
</code></pre>
Add a key-value pair:
<pre><code>obj[key] = value;
</code></pre>

blocks|key|735660|text|实际上，“关联数组”与ECMAScript中的“类似数组的对象”非常相似。即使数组也是ECMAScript中的对象，除了具有数字键(仍是背景中的字符串)和.length属性，以及一些从Array.prototype继承的方法。|type|unstyled|depth|inlineStyleRanges|offset|length|style|CODE|entityRanges|data|735661|因此，Perl散列和ECMAScript对象的行为类似。您可能不知道，您不仅可以通过点访问对象属性，还可以使用括号和字符串访问对象属性，例如|735662|var+myObj+=+{+foo:+42+};

myObj.foo;+//+42
myObj['foo'];+//+42|code-block|syntax|javascript|735663|了解了这一点，您还可以在.中使用密钥|735664|var+myObj+=+{+};
myObj['hello.foo.world']+=+42;|735665|当然，您只能使用括号表示法来访问该键。|735666|entityMap^0|25|7|2K|F|0|0|0|C|1|0|0|0^^$0|@$1|2|3|4|5|6|7|U|8|@$9|V|A|W|B|C]|$9|X|A|Y|B|C]]|D|@]|E|$]]|$1|F|3|G|5|6|7|Z|8|@]|D|@]|E|$]]|$1|H|3|I|5|J|7|10|8|@]|D|@]|E|$K|L]]|$1|M|3|N|5|6|7|11|8|@$9|12|A|13|B|C]]|D|@]|E|$]]|$1|O|3|P|5|J|7|14|8|@]|D|@]|E|$K|L]]|$1|Q|3|R|5|6|7|15|8|@]|D|@]|E|$]]|$1|S|3|-4|5|6|7|16|8|@]|D|@]|E|$]]]|T|$]]

Actually, an &quot;associative array&quot; is pretty much the same as an &quot;array-like object&quot; in ECMAScript. Even arrays are objects in ECMAScript, just with the exception to have numeric keys (which are still strings in the background) and a <code>.length</code> property, along with some inherited methods from <code>Array.prototype</code>.
So, a Perl hash and an ECMAScript object behave similarly. You might not know that you can access object properties not only via a dot, but also with brackets and strings, like
<pre><code>var myObj = { foo: 42 };

myObj.foo; // 42
myObj['foo']; // 42
</code></pre>
Knowing that, you can also use keys with <code>.</code>
<pre><code>var myObj = { };
myObj['hello.foo.world'] = 42;
</code></pre>
Of course, you can access that key only with the bracket notation.

blocks|key|735734|text|如果您愿意，可以在JavaScript对象(也称为关联数组)的键名中使用.；它们被接受时没有任何问题。一个小缺点是你不能使用带虚线的快捷键，例如|type|unstyled|depth|inlineStyleRanges|offset|length|style|CODE|entityRanges|data|735735|var+x+=+{};
x['hello']+=+'there';
alert(x.hello);|code-block|syntax|javascript|735736|是完全可以接受的，并会弹出一个带有“there”的警告。但是如果你使用一个点分隔的名字：|735737|var+x+=+{};
x['this.is']+=+'sparta';
alert(x.this.is);|735738|将失败，因为JavaScript将在不存在的x对象中查找名为this的属性。只有this.is属性。|735739|entityMap^0|10|1|0|0|0|0|U|4|14|7|0^^$0|@$1|2|3|4|5|6|7|S|8|@$9|T|A|U|B|C]]|D|@]|E|$]]|$1|F|3|G|5|H|7|V|8|@]|D|@]|E|$I|J]]|$1|K|3|L|5|6|7|W|8|@]|D|@]|E|$]]|$1|M|3|N|5|H|7|X|8|@]|D|@]|E|$I|J]]|$1|O|3|P|5|6|7|Y|8|@$9|Z|A|10|B|C]|$9|11|A|12|B|C]]|D|@]|E|$]]|$1|Q|3|-4|5|6|7|13|8|@]|D|@]|E|$]]]|R|$]]

You can use <code>.</code> in key names on JavaScript objects (AKA associative arrays) if you'd like; they're accepted without issue. The minor drawback is you can't use shortcut notations with the dotted keys, e.g.
<pre><code>var x = {};
x['hello'] = 'there';
alert(x.hello);
</code></pre>
is perfectly acceptable and will pop up an alert with 'there' in it. But if you use a dotted name:
<pre><code>var x = {};
x['this.is'] = 'sparta';
alert(x.this.is);
</code></pre>
will fail, as JavaScript will look for an attribute named <code>this</code> in the x object, which does not exist. There is only the <code>this.is</code> attribute.

In my script there is a need to create a hash table, and I searched in google for this. Most of the folks are recommending JavaScript object for this purpose. The The problem is some of the keys in the hash table have a &quot;.&quot; in them. I am able to create these keys easily with the associative arrays.
I don't understand why associative arrays are bad. The first thing that is mentioned on the sites that I looked at is the length property.
I am coming from the Perl background, where I used hashes. Most common uses were to get the value from a key, check if a key exists, delete a key-value pair, and add a key-value pair. If these are my common uses, can I safely use an associative array?

Associative array versus object in JavaScript

Perl

在我的脚本中，需要创建一个哈希表，我在google中进行了搜索。为此，大多数人都推荐使用JavaScript object。问题是哈希表中的一些键有一个“.在他们身上。我可以使用关联数组轻松地创建这些键。我不明白为什么关联数组不好。在我查看的站点上提到的第一件事是length属性。我来自Perl的背景，在那里我使用了散...

问关联数组与JavaScript中的对象
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