Bash Conditional Statements

If-Else Statement

There should always have space around the condition and [].
The variables and values should be specified inside " "
There has be to space between = sign, the variable and the value this is how comparison is done in shell else it will be considered as assignment operation.

NAME="David"
if [ "$NAME" = "David" ];
then
	echo "Hello $NAME"
else
	echo "Invalid User"
fi

Test Command

-e: Check if file exist, -d: Check if directory exist
-b: Block special file (Non text files), -c: Character special file (Text files)
-s: Check if file is empty

test Command Man Page

Unix / Linux - Shell File Test Operators Example

if [ -d /usr/share/wordlists ];
then
	echo "The folder exist"
elif [ -e /usr/share/wordlists/rockyou.txt ];
	echo "The file exist"
else
	echo "File and folder does not exist"
fi

Ternary Operator

statement && condition1 || condition2

Case Statement

case $vehicle in
	"car" | "jeep") 
		echo "You have selected a Car"
		;;
	"truck")
		echo "You have selected an truck"
		;;
	*)
		echo "Invalid Option"
		;;
esac

The break and continue keyword is also present in shell scripting