Nested-if-statement-examples-bash-script Case Statement Case 语句类似于 if 语句,但带有多个 elif。bash 脚本中的 Case 语句展开表达式,然后尝试找到与所有模式的匹配。当找到匹配时,将执行所有语句,直到双分号 “;;”。如果没有找到匹配,则将执行 “*)” 模式下提到的语句。 Syntax : case expression in pat...
*)statementnesaccase、in 和 esac 都是 Shell 关键字，expression 表示表达式，pattern 表示匹配模式。e...
2. How do I write an if statement in a shell script? Writing an if statement in a shell script involves specifying a condition and the actions to take if the condition is true. Here’s the basic syntax: if[condition];then# code to execute if condition is trueelse# code to execute if...
Example Script number.sh #!/bin/bash echo -n “Enter a number 1 < x < 10: " read num if [ “$num” -lt 10 ]; then if [ “$num” -gt 1 ]; then echo “$num*$num=$(($num*$num))” else echo “Wrong insertion !” fi else echo “Wrong insertion !” fi ...
if you want to select one of many blocks of code to execute. It checks expression 1, if it is true executes statement 1,2. If expression1 is false, it checks expression2, and if all the expression is false, then it enters into else block and executes the statements in the else block...
Now that you are aware of the various comparison expressions let's see them in action in various examples. 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: ...
1. How to use in if condition in shell script? To use an if condition in a shell script, you can follow the basic syntax of an if statement. Here’s an example: if[condition];then# code to execute if condition is truefi For example, to check if a file exists: ...
A Shell script usually needs to test if a command succeeds or a condition is met. In Bash, this test can be done with a Bash if statement. As with any other programming language, Bash comes with conditional expressions that allow you to test for conditions and alter the control flow if ...
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...
So far all the if else statement you saw were used in a proper bash script. That's the decent way of doing it but you are not obliged to it. When you just want to see the result in the shell itself, you may use the if else statements in a single line in bash. Suppose you hav...