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Basic Pascal Tutorial/Chapter 3/CASE/zh CN: what changed

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Title: Basic Pascal Tutorial/Chapter 3/CASE/zh CN

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1+3Cb - CASE语句 (原作者: Tao Yue, 状态: 未更改)
2+
3+根据条件执行CASE语句。CASE语句计算每个表达式,以进行选择,它可以是[[Const/zh CN|常量]]、范围,或将它们以[[Comma/zh CN|逗号]]分隔的列表。用[[Colon/zh CN|冒号]]分隔每个语句块。
4+
5+假设一种分支方式是:如`b`是`1、7、2037、5`,你可以这样:
6+```
7+if (b = 1) or (b = 7) or (b = 2037) or (b = 5) then
8+ 语句1
9+ else
10+ 语句2;
11+```
12+
13+在这种情况下,使用`CASE语句`会变得简单:
14+```
15+case b of
16+ 1,7,2037,5: 语句1;
17+ else 语句2
18+ end;
19+```
20+
21+`CASE语句`的格式是:
22+```
23+case 选择器 of
24+ 列表1: 语句1;
25+ 列表2: 语句2;
26+ ...
27+ 列表n: 语句n;
28+ else 语句;
29+ end;
30+```
31+
32+`else`部分是可选的,`else`表示其他情况。
33+
34+选择器是一个有序数据类型的任何变量,但不能使用实数。
35+
36+Note that the lists must consist of literal values. That is, you must use constants or hard-coded values -- you cannot use variables.
37+
38+(~~注意,该列表必须包含文本值。也就是说,您必须使用常量或硬编码值——您不能使用变量。~~ )
39+
40+[[Basic Pascal Tutorial/Chapter 3/IF/zh CN|上一页]] | [[Basic Pascal Tutorial/Contents/zh CN|目录]] | [[Basic Pascal Tutorial/Chapter 3/FOR..DO/zh CN|下一页]]
41+---|---|---
42+
43+---
44+*From the Free Pascal wiki, page "CASE/zh CN", as the Internet Archive kept it on 2023-03-22. Copyright stays with the author who wrote it, according to the old wiki's [[Licensing]] page. If you have concerns about this material, [message the admin](/wiki-contact).*

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