linuxhint@:~$basht2.sh Enter a number:8 linuxhint@:~$ Example 3: If statement in bash on less than a number In addition to-eqfor equality you can also try-lt -le -gt -getest conditions for less than, less than or equal, greater than or greater then or equal respectively. Below...
Using else if statement in bash You can use an elif (else-if) statement whenever you want to test more than one expression (condition) at the same time. For example, the followingage.shbash script takes your age as an argument and will output a meaningful message that corresponds to your...
Running a with if statement example in bash 你是否注意到,当数字为偶数时,脚本会告诉你,但当数字为奇数时,脚本不会显示任何内容?让我们使用 else 来改进这个脚本。 使用if else 语句 现在我在前面的脚本中添加了一条 else 语句。这样,当你得到一个非零模数(因为奇数不能除以 2)时,它将进入 else 块。
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 $x in 100) 9[0-9]) 这个语句的意思是如果$name为空,那么X=X成立折执行下面的结果; if [ "X$name" != "x" ] 写脚本的时候很多时候需要用到回传命令,$?如果上一个命令执行成功,回传值为0,否则...
Example 4 Within our last example, we will be checking whether the simple Bash file is located in the current home directory or other folders or not. For this, we will be using the “-f” option within the if-not operator condition. So, we have initialized a FILE variable with the fil...
Example 1: Numeric Comparison !/bin/bash count=10 if [ $count -gt 0 ] then echo "Count is positive." else echo "Count is zero or negative." fi Example 2: String Comparison !/bin/bash name="Alice" if [ "$name" == "Alice" ] ...
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 nested if as shown belo...
/bin/bash filename=”example.txt” if [ -e $filename ] then echo “$filename exists.” else echo “$filename does not exist.” fi “` 在这个例子中,使用了-e选项来判断文件是否存在。如果文件存在,则输出”$filename exists.”,否则输出”$filename does not exist.”。
Running a script with if statement example in bash 你是否注意到,当数字为偶数时,脚本会告诉你,但当数字为奇数时,脚本不会显示任何内容? 让我们使用 else 来改进这个脚本。 使用if else 语句 现在我在前面的脚本中添加了一条else语句。这样,当你得到一个非零模数(因为奇数不能除以 2)时,它将进入else块。
注意，test是一个外部程序，需要衍生出对应的进程，而[是Bash的一个内部函数，因此后者的执行效率更高。