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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+``` pascal
8+if (b = 1) or (b = 7) or (b = 2037) or (b = 5) then
9+ 语句1
10+else
11+ 语句2;
12+```
13+
14+在这种情况下,使用`CASE语句`会变得简单:
15+
16+``` pascal
17+case b of
18+ 1,7,2037,5: 语句1;
19+ else 语句2
20+end;
21+```
22+
23+`CASE语句`的格式是:
24+
25+``` pascal
26+case 选择器 of
27+ 列表1: 语句1;
28+ 列表2: 语句2;
29+ ...
30+ 列表n: 语句n;
31+ else 语句;
32+end;
33+```
34+
35+`else`部分是可选的,`else`表示其他情况。
36+
37+选择器是一个有序数据类型的任何变量,但不能使用实数。
38+
39+Note that the lists must consist of literal values. That is, you must use constants or hard-coded values -- you cannot use variables.
40+
41+(~~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。~~)
42+
43+| | | |
44+|----|----|----|
45+| [[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]] |
46+
47+---
48+*From the Free Pascal wiki, page "Basic Pascal Tutorial/Chapter 3/CASE/zh CN", as it stood on 2022-08-20 after a change by Kai Burghardt, out of the wiki's dump of 2024-05-26. 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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