linux case 流程图

case $variable in
    pattern1)
        commands1
        ;;
    pattern2)
        commands2
        ;;
    *)
        default_commands
        ;;
esac

#!/bin/bash

echo "请输入一个数字 (1-3):"
read number

case $number in
    1)
        echo "你选择了选项1"
        ;;
    2)
        echo "你选择了选项2"
        ;;
    3)
        echo "你选择了选项3"
        ;;
    *)
        echo "无效的选择"
        ;;
esac

开始
 |
 V
+-------------------+
| 读取变量          |
+-------------------+
 | 是                |
 | pattern1          |
 V                 |
+-------------------+
| 执行 commands1   |
+-------------------+
 | 否                |
 +-------------------+
 | 是                |
 | pattern2          |
 V                 |
+-------------------+
| 执行 commands2   |
+-------------------+
 | 否                |
 +-------------------+
 | 是                |
 | * (默认)          |
 V                 |
+-------------------+
| 执行 default_commands |
+-------------------+
结束