Bash shell case statement is similar to switch statement in C. It can be used to test simple values like integers and characters. Case statement is not a loop, it doesn’t execute a block of code for n number of
The following article describes the basic syntax and includes a simple example of the BASHCASEstatement usage. TheCASEstatement is the simplest form of theIF-THEN-ELSEstatement in BASH. You may use theCASEstatement if you need theIF-THEN-ELSEstatement with manyELIFelements. With the BASHCASEstat...
In this example, the script first checks if ‘a’ is greater than ‘b’. If it’s not, it moves on to the ‘elif’ statement to check if ‘a’ is greater than ‘c’. If neither condition is met, it executes the ‘else’ statement, which in this case, prints ‘a is not greate...
当您在shell中有多个不同的选择时,Bash case语句可用于简化复杂的条件。使用case语句而不是嵌套的if语句将让您使bash脚本更易读,更易于维护。 Bash case语句与Javascript或C switch语句具有类似的概念。主要区别在于,与C switch语句不同,Bash case语句一旦找到一个并执行与该模式关联的语句,就不会继续搜索模式匹配。
到目前为止,您应该很好地理解如何编写bash case语句。它们通常用于从命令行将参数传递给shell脚本。例如,init脚本使用case语句来启动,停止或重新启动服务。 如果您有任何问题或反馈,请随时发表评论。 如果你喜欢我们的内容可以选择在下方二维码中捐赠我们,或者点击广告予以支持,感谢你的支持 ...
statement3 . fi fi If statement and else statement could be nested in bash. The keyword “fi” indicates the end of the inner if statement and all if statement should end with the keyword “fi”. The “if then elif then else fi” example mentioned in above can be converted to the nes...
example:表述数字范围的时候 可以使用if可以是使用case if [ $x -gt 90 -o $x -lt 100 ] case $x in 100) 9[0-9]) if [ "X$name" != "x" ] 这个语句的意思是如果$name为空,那么X=X成立折执行下面的结果; 写脚本的时候很多时候需要用到回传命令,$?如果上一个命令执行成功,回传值为0,否则...
Example 2: Using Multiple Patterns The Bashcasestatement allows multiple patterns in a clause. When the input variable matches any provided patterns, the script executes the commands in that clause. This script below prompts the user to enter a month and outputs the number of days. Depending on...
In order to check if a given file exists, users can perform conditional tests. In this case, we’ll useanifstatement with a-fflag. The flag checks if a given file exists and is a regular file. Start by creating the script file: ...
caseis a conditional statement that executes specific actions based on a matching pattern: $ cat case_example.sh #!/usr/bin/env bash case word in pattern1) action1 ;; pattern2) action2 ;; ... *) default_action ;; esac Let’s interpret this code snippet as shown bycat: ...