Solved

ref out parameters.

Posted on 2008-06-16
8
317 Views
Last Modified: 2013-12-17
I have the following:


            InitialPrices.localhost.InitialPriceReportingService WS
               = new InitialPrices.localhost.InitialPriceReportingService();
            int Id = 0;
            string Status = null;
            WS.GetGradeCodeDetailID("WHT", ref Id, ref Status); // These values need to comback from the webservice the id and status.
I am not sure how to work with ref and out.

The method is as following:
[WebMethod(Description = "Get Grade Code Detail based on the grade name")]
        public void GetGradeCodeDetailID(string GradeName, out int GradeCodeDetailID, out string Status)
        {
            string procedureName = "init_price.PRICE_LIST_REPORTING.get_grade_code_dtl_id";
            try
            {
                Database db = DatabaseFactory.CreateDatabase("InitialPrices.Properties.Settings.ConnectionString");
                DbCommand dbCommand = db.GetStoredProcCommand(procedureName);

                db.AddInParameter(dbCommand, "p_grade_name", DbType.String, GradeName);
                db.AddOutParameter(dbCommand, "p_grade_code_dtl_id", DbType.Int32, 4);
                db.AddOutParameter(dbCommand, "p_status", DbType.String, 7);
                db.ExecuteNonQuery(dbCommand);
               

                GradeCodeDetailID = Convert.ToInt32( dbCommand.Parameters[1].Value, CultureInfo.InvariantCulture);
                Status = dbCommand.Parameters[2].Value.ToString();
            }
            catch (Exception ex)
            {
                throw (ex);
            }

            return;
        }


0
Comment
Question by:mathieu_cupryk
  • 3
  • 2
  • 2
  • +1
8 Comments
 
LVL 7

Accepted Solution

by:
Zippit earned 500 total points
ID: 21798186
change this line:
WS.GetGradeCodeDetailID("WHT", ref Id, ref Status);

to:
WS.GetGradeCodeDetailID("WHT", out Id, out Status);

after the call to 'GetGraceCodeDetailID' the variables ID and Status will have the output values in them.
0
 
LVL 7

Expert Comment

by:Zippit
ID: 21798214
ref and out are used mainly the same way.  They allow the called function to change the values of the parameters and have the updated values returned to the caller.  The difference between the two is that a ref parameter must be initialized before the call to the function is made.  An out parameter does not need to have it's value initialized before the function call is made as the function will initialize the value.

If the parameter is declared as an out parameter, like the following:

public function muFunction(ref int param1)

then it needs to be called as follows:

int myParam1 = 1234;
myFunction(ref myParam1);
// now do something with myParam1 and its new value

if the function uses an out parameter like the following:

public function muFunction(ref int param1)

then it is used and called as follows:

int myParam1;
myFunction(out myParam1);
// now do something with myParam1 and its new value
0
 
LVL 29

Expert Comment

by:anarki_jimbel
ID: 21798255
No much difference between 'ref' and 'out'. But you need to know it.

An argument passed to a ref parameter must first be initialized. 'out' parameter does not have to be explicitly initialized before being passed to an out parameter. This is major difference. So you may use either of two.

See msdn for more information. They have good example and good explanations:

'ref':
http://msdn.microsoft.com/en-us/library/14akc2c7(VS.71).aspx

'out':
http://msdn.microsoft.com/en-us/library/t3c3bfhx(VS.71).aspx
0
3 Use Cases for Connected Systems

Our Dev teams are like yours. They’re continually cranking out code for new features/bugs fixes, testing, deploying, testing some more, responding to production monitoring events and more. It’s complex. So, we thought you’d like to see what’s working for us.

 
LVL 15

Expert Comment

by:Solar_Flare
ID: 21799260
if you can, it is a good idea not to use out and ref parameters for web services as they are stateless.

if you must then make sure you read http://kbalertz.com/322624/Proxy-Class-First-Parameter-Service-Method-Returns-Return-Value-Reference.aspx
0
 

Author Comment

by:mathieu_cupryk
ID: 21805589
I get a no overload for:

 InitialPrices.InitialPriceReportingServiceWS.InitialPriceReportingService WS = new InitialPrices.InitialPriceReportingServiceWS.InitialPriceReportingService();
                            int GradeCodeDetailID;
                            string Status;
                           
                            WS.GetGradeCodeDetailID(gradeName, out GradeCodeDetailID, out Status);
                         


in the web service:

0
 

Author Comment

by:mathieu_cupryk
ID: 21805593
[WebMethod]
        public void GetGradeCodeDetailID(string gradeName, out int GradeCodeDetailID, out string Status)
        {

            string procedureName = "init_price.PRICE_LIST_REPORTING.get_grade_code_dtl_id";
            try
            {
                Database db = DatabaseFactory.CreateDatabase("InitialPrices.Properties.Settings.ConnectionString");
                DbCommand dbCommand = db.GetStoredProcCommand(procedureName);

                db.AddInParameter(dbCommand, "p_grade_name", DbType.String, gradeName);
                db.AddOutParameter(dbCommand, "p_grade_code_dtl_id", DbType.Int32, 4);
                db.AddOutParameter(dbCommand, "p_status", DbType.String, 7);
                db.ExecuteNonQuery(dbCommand);


                GradeCodeDetailID = Convert.ToInt32(dbCommand.Parameters[1].Value, CultureInfo.InvariantCulture);
                Status = dbCommand.Parameters[2].Value.ToString();
            }
            catch (Exception ex)
            {
                throw (ex);
            }
       }
0
 
LVL 29

Expert Comment

by:anarki_jimbel
ID: 21807272
Yeah, well. I'd agree with Solar_Flare. But I can't really see any problems for this specific case. And I'd use 'out' parameters too, not 'ref'.
0
 

Author Closing Comment

by:mathieu_cupryk
ID: 31467800
Great job!
0

Featured Post

DevOps Toolchain Recommendations

Read this Gartner Research Note and discover how your IT organization can automate and optimize DevOps processes using a toolchain architecture.

Question has a verified solution.

If you are experiencing a similar issue, please ask a related question

Suggested Solutions

A long time ago (May 2011), I have written an article showing you how to create a DLL using Visual Studio 2005 to be hosted in SQL Server 2005. That was valid at that time and it is still valid if you are still using these versions. You can still re…
Entity Framework is a powerful tool to help you interact with the DataBase but still doesn't help much when we have a Stored Procedure that returns more than one resultset. The solution takes some of out-of-the-box thinking; read on!
Windows 10 is mostly good. However the one thing that annoys me is how many clicks you have to do to dial a VPN connection. You have to go to settings from the start menu, (2 clicks), Network and Internet (1 click), Click VPN (another click) then fi…
Established in 1997, Technology Architects has become one of the most reputable technology solutions companies in the country. TA have been providing businesses with cost effective state-of-the-art solutions and unparalleled service that is designed…

813 members asked questions and received personalized solutions in the past 7 days.

Join the community of 500,000 technology professionals and ask your questions.

Join & Ask a Question

Need Help in Real-Time?

Connect with top rated Experts

19 Experts available now in Live!

Get 1:1 Help Now