access by key

基本解释

In all cases, the return value of the method can be processed using a foreach() loop, and you can also access specific values by key as needed.
所有方法的返回值都可用 foreach() 循环来处理，需要的话也可按键访问特定的值。
When you specify a caption for your menu item, you can also specify an access key by placing an '&' before the character to be used as the access key.
为菜单项指定标题时，还可以通过在要用作访问键的字符前放置一个“&”来指定访问键。
The KeyedFile class represents a system file that has access by key while the SequentialFile class represents a system file that has access by record number.
KeyedFile 类表示一个通过密钥访问的系统文件，而 SequentialFile 类表示一个通过记录编号访问的系统文件。

As you can see in the screen shot below (from the Ars Technica article), you can provide links to your files (either containing the key so someone can access them directly or by providing them with the key separately) but you are prompted with a caution about not transmitting the keys through insecure channels and a far-reaching copyright warning.
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Julian Sanchez of the Cato Institute has previously pointed out that a downside to creating an easy access key for the feds, is that an easy access key then exists and can be stolen by hackers.
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Unless the Canadian government accedes to his views, he seems ready to put the brakes on future oil sands development by curtailing Canadian access to its key export market.
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