For this, we need to utilize the not operator “!” with the “if” statement in the bash script. Let’s discuss the use of the “if-not” operator in Bash programming with the help of some examples. Get started with the new Bash file creation while using the terminal shell of the ...
-eqequal,检测两个数是否相等,相等返回 true。[ $a -eq $b ] 返回 false。-nenot equal,检测...
While ‘else if’ is a powerful tool for handling multiple conditions in bash scripting, it’s not the only one. An alternative approach is the ‘case’ statement. ‘Case’ statements can be more readable and easier to maintain than a long list of ‘elif’ conditions, especially when you’...
echo "The file does not exist." fi If-elif-else Statement 在bash 脚本中,如果希望使用 if 语句应用多个条件,则使用 if elif else。在这种类型的条件语句中,如果满足第一个条件,则执行下面的代码,否则检查下一个 if 条件,如果不匹配,则执行下面的 else 语句中提到的命令。其语法和示例如下所示。 Syntax ...
Statement(s) to be executed if expression is true else Statement(s) to be executed if expression is not true fi ## 如果 expression 返回 true,那么 then 后边的语句将会被执行;否则,执行 else 后边的语句。 ## 如果 then 和 if [ expression ]同一行,则[ expression ]和then之间必须有 ; ...
statement4 fi Note: if语句进行判断是否为空 [ "$name” = "" ] 等同于 [ ! "$name" ] [ -z "$name" ] Note: 使用if语句的时候进行判断如果是进行数值类的 ,建议使用 let(())进行判断 对于字符串等使用test[ ] or [[ ]] 进行判断 ...
从你的代码中我可以看出,这(使用bash 4.3或更高版本来测试-v的数组索引存在性)似乎是你想要做的...
问在bash中使用内联if-statement添加命令参数ENexport export命令将会使得被 export 的变量在运行的...
1. Bash If..then..fi statement if [ conditional expression ] then statement1 statement2 . fi This if statement is also called as simple if statement. If the given conditional expression is true, it enters and executes the statements enclosed between the keywords “then” and “fi”. If th...
Use if statement in bash Let's create a script that tells you if a given number is even or not. Here's my script namedeven.sh: #!/bin/bash read -p "Enter the number: " num mod=$(($num%2)) if [ $mod -eq 0 ]; then ...