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。
if [ $num -lt 0 ]; then echo "Number $num is negative" elif [ $num -gt 0 ]; then echo "Number $num is positive" else echo "Number $num is zero" fi 让我运行它来涵盖这里的所有三种情况: Running a script with bash elif statement 用逻辑运算符组合多个条件 到目前为止,一切都很好。但...
If-statement-Bash-Script-Example if-else Statement 除了普通的 if 语句之外,我们还可以用 else 块扩展 if 语句。基本思想是,如果语句为真,则执行 if 块。如果语句为假,则执行 else 块。 Syntax : if [ condition_command ] then command1 command2 …….. last_command else command1 command2 …….. ...
if else condition bash if shell if bash if else bash script if bash linux script shell script if if else branch if shell bash if then bash if then else linux shell if bash if elif fi if linux shell if else bash script if shell script if else if condition in shell script if else in...
if[-s/tmp/hoge.txt];then# 1バイトでも中身があれば何もしないelse# 0バイトだったら消すrm/tmp/hoge.txtfi Bourneシェルやzshを使っている場合はこれで大丈夫。ところがBashで動かそうとするとエラーになってしまう。 Bashでは、thenやelif、else節の後に有効なコードを置かずに済ませる...
[ s1 ] (true if s1 is not empty, else false) [ -n s1 ] (true if s1 has a length greater then 0, else false) [ -z s2 ] (true if s2 has a length of 0, otherwise false) Example Script number.sh #!/bin/bash echo -n “Enter a number 1 < x < 10: " ...
/bin/bash read -p "Enter the number: " num mod=$(($num%2)) if [ $mod -eq 0 ]; then echo "Number $num is even" else echo "Number $num is odd" fi Let's run it again with the same numbers: As you can see, the script is better as it also tells you if the number is...
/bin/bashread-p"Enter the number: "nummod=$(($num%2))if[$mod-eq0];thenecho"Number$numis even"elseecho"Number$numis odd"fi 1. 2. 3. 4. 5. 6. 7. 8. 让我们用相同的数字再次运行它: Running a bash script that checks odd even number...
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...
1、if语法格式 1.1 if格式 if condition; then commands; fi 1.2 else if 和 else if c...