If conditions for stored procedure

[murthychvrm]

i wrote the stored procedure like as below .it was executed successfully.no w i want to write if conditions for this stored procedure at check all conditions if i give fromdate and todate this is first case.second is not give fromdate and give todate.third give fromdate and not give todate.if i not give fromdate and not give todate.
how to write code for above cases?

stored procedure:

set ANSI_NULLS ON
set QUOTED_IDENTIFI ER ON
go
alter PROCEDURE [dbo].[sp_selectgunnie itemtran]
(@fromdate datetime,@todat e datetime)
--(@fromdate datetime,@todat e datetime,@Date datetime,@Issue _No int,@Item_Desc varchar(50),@Qu antity int,@Agent_name varchar(50),@Ag ent_Code int)
AS
BEGIN
select
riq.Issue_No,ri q.Item_Desc ,riq.Quantity ,ri.Date,
a.Agent_name,a. Agent_Code
from
Rice_Agent_Mast er a,Rice_Issues ri,Rice_Issues_ Qty riq

where
ri.Date between @fromdate and @todate
and
riq.Agent_Code= a.Agent_Code

[code green]

check all conditions if i give fromdate and todate this is first case.second is not give fromdate and give todate.third give fromdate and not give todate.if i not give fromdate and not give todate.
how to write code for above cases

It is roughly

CASE WHEN (fromdate IS NULL AND todate IS NULL) THEN fault 
ELSE fromdate IS NULL THEN second
ELSE todate IS NULL THEN third
ELSE first

Apologies if syntax is wrong