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Sort Expression as a parameter to Stored Procedure

How to send the sort expression as a parameter to Stored Procedure?

This is the problem that I faced in one of my recent tasks. When I was given this work,
without much thought, started with the following lines.


CREATE PROCEDURE GetProcedure
@sortExp varchar(25)
AS
select ProcedureID,Items,[Value] from Procedure
order by @sortExp DESC

When I tried to run this stored procedure, I got an unexpected error saying,

Msg 1008, Level 16, State 1, Procedure GetProcedure, Line 5
The SELECT item identified by the ORDER BY number 1 contains a variable as part of the expression identifying a column position. Variables are only allowed when ordering by an expression referencing a column name.

Then, I started to think about the error and soon I traced the fault.
The problem is that- SQL Server is not recognizing the given parameter as a table column. By default all the parameters are considered to be of some data type. They can't be converted into type 'Column'. As "Order by" statement needs a column name, server is throwing an error.

What is the Solution?
The solution for the problem is using a "CASE" statement with the parameter.
Then the procedure will look like

CREATE PROCEDURE GetProcedure
@sortExp varchar(25)
AS
select ProcedureID,Items,[Value] from Procedure
order by CASE @sortExp
When 'ProcedureID' then ProcedureID
When 'Items' then Items
When 'Value' then Value
End
DESC

Now,What if you want to send another parameter for Direction...?
then, you have to check that in if-else loop or another CASE Statement.
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