DropDown Lsit Filter Search Stored Procedure

CREATE PROCEDURE [dbo].[SR_SelectProjectsDetailsForSpecificStatusWithSpecificUser]
@Portal_User_ID INT,
@Project_status_code INT,
@Category_Code int
AS

BEGIN

SET NOCOUNT ON
IF(ISNULL(@Project_status_code,0) > 0)
BEGIN
SELECT Project.Project_Code, Project.Project_Name, Project.Project_type_Code, Project.Project_Type_Details, Project.Project_status_code,
Project.Project_DeadLine, ProjectCategory.Category_Name, ProjectStatus.Project_Status_Name, ProjectType.Project_Type_Name,
ProjectResource.Portal_User_ID, ProjectResource.Role_Code, ProjectResource.Project_code AS Expr1
FROM Project (NOLOCK)
INNER JOIN ProjectStatus (NOLOCK)
ON Project.Project_status_code = ProjectStatus.Project_Status_code
INNER JOIN ProjectCategory (NOLOCK)
ON Project.Category_Code = ProjectCategory.Category_Code
INNER JOIN ProjectType (NOLOCK)
ON Project.Project_type_Code = ProjectType.Project_Type_Code
INNER JOIN ProjectResource (NOLOCK)
ON Project.Project_Code = ProjectResource.Project_code
WHERE Project.Project_status_code=@Project_status_code and ProjectResource.Portal_User_ID=@Portal_User_ID and Project.Category_Code=@Category_Code
ORDER BY Project.Project_Code DESC

END
ELSE
BEGIN
SELECT Project.Project_Code, Project.Project_Name, Project.Project_type_Code, Project.Project_Type_Details, Project.Project_status_code,
Project.Project_DeadLine, ProjectCategory.Category_Name, ProjectStatus.Project_Status_Name, ProjectType.Project_Type_Name,
ProjectResource.Portal_User_ID, ProjectResource.Role_Code, ProjectResource.Project_code AS Expr1
FROM Project (NOLOCK)
INNER JOIN ProjectStatus (NOLOCK)
ON Project.Project_status_code = ProjectStatus.Project_Status_code
INNER JOIN ProjectCategory (NOLOCK)
ON Project.Category_Code = ProjectCategory.Category_Code
INNER JOIN ProjectType (NOLOCK)
ON Project.Project_type_Code = ProjectType.Project_Type_Code
INNER JOIN ProjectResource (NOLOCK)
ON Project.Project_Code = ProjectResource.Project_code
WHERE ProjectResource.Portal_User_ID=@Portal_User_ID and Project.Category_Code=@Category_Code
ORDER BY Project.Project_Code DESC

END
SET NOCOUNT OFF

END