枚举类型：项数限制？ [英] Enumerated Type: Limit to number of items?

问题描述

在Delphi中，枚举类型中可以包含的项数是否有限制？我需要创建一个可能包含数百个项目的枚举类型，并想要确保例如255个项目没有限制。

Is there a limit in Delphi to the number of items you can have in an enumerated type? I need to create an enumerated type that might have several hundred items, and want to make sure there is not a limit at 255 items for example.

type 
  TMyType = (mtOne, mtTwo, mtThree, ..., mtThreeHundred);

推荐答案

我在德国德尔福市最多发现65535个物品

I found a maximum of 65535 items in a german Delphi book.

在对文档进行一些挖掘之后，我找到了相应的部分：

After some digging in the documenation I found the respective section:

枚举类型

如果枚举的
不超过256个值并且在，则枚举类型存储为
无符号字节。 > {$ Z1} 状态（默认
）。如果枚举类型的
多于256个值，或者类型
是在 {$ Z2} 状态中声明的，则为
存储为无符号字。如果在
{$ Z4} 状态中声明了
枚举类型，则将其存储为
无符号双字。 / p>

An enumerated type is stored as an unsigned byte if the enumeration has no more than 256 values and the type was declared in the {$Z1} state (the default). If an enumerated type has more than 256 values, or if the type was declared in the {$Z2} state, it is stored as an unsigned word. If an enumerated type is declared in the {$Z4} state, it is stored as an unsigned double-word.

因此，实际上最多应该有4294967295（ $ FFFFFFFF ）项目。

So in fact there should be a possible maximum of 4294967295 ($FFFFFFFF) items.

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