case in sql server 2008 r2

We can use CASE in single line query in SQL Server. The given below example might help you.

DECLARE  @NET VARCHAR(10)    
SET @NET ='3G'

SELECT (CASE @NET WHEN '4G' THEN 1 WHEN '3G' THEN 2 WHEN '2G'  THEN 3 END) AS NETWORKID

Result : 

NETWORKID is 2