Case Statement

The case statement can be used to match several values against one variable.
The case statement is very useful when you want to provide options for the users.

Example:
Select 1 to say " Hello "
Select 2 to say " Good Bye "

Case Statement in Linux Shell Scripting

Syntax:

 
case  $variable-name  in
	pattern1)  { code to execute };;
	pattern2)  { code to execute };;
	patternN)  { code to execute };;
	*)
	{ code to execute };;
esac
		   

Example:
case.sh

 
#!/bin/sh
# Get the value from the user
echo "Enter a digit between [ 1 and 4 ]"
echo "Enter a value for the variable x:"
read x

case $x in
   "1") echo "You have entered One";;
   "2") echo "You have entered Two";;
   "3") echo "You have entered Three";;
   "4") echo "You have entered Four";;
   *) echo "Sorry, You have entered a value beyond limit";;
esac
          

Result:
./case.sh

 
Enter a digit between [ 1 and 4 ]
Enter a value for the variable x:
4
You have entered Four
          

The case.sh script takes the value for x from the user and process it accordingly.
In the above example, we entered 4 as the value of x. Try this example script with various other values and see the results. Also try adding more options to the case statement.