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.
所有方法的返廻值都可用 foreach() 循環來処理，需要的話也可按鍵訪問特定的值。
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.
爲菜單項指定標題時，還可以通過在要用作訪問鍵的字符前放置一個“&”來指定訪問鍵。
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 類表示一個通過密鈅訪問的系統文件，而 SequentialFile 類表示一個通過記錄編號訪問的系統文件。

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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