WCF service referencing in my app

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C#

C#4.0

HI,

I am busy building a windows forms application that needs to be able to use a WCF to connect to the work Database.

I get how to reference it but now I was told to create a DAL project and Classes project to contain all my methods and that's where I get really confused because my Classes.cs has SQL commands in it and now I have to call the method in the WCF and then get that method in the app it self here is the code that I use in the classes.cs but how would I then reference this in the WCF and then to the App it self via code?

private DataTable getLoginDetails(string username)
        {

            
            SqlCommand sqlcmd = new SqlCommand("sp_GetLoginDetails", sqlConn);
            sqlcmd.CommandType = CommandType.StoredProcedure;

            sqlcmd.Parameters.Add("@UserName", SqlDbType.VarChar).Value = username;
            DataTable dtUser = new DataTable();
            sqlConn.Open();
            SqlDataReader sqlDR = sqlcmd.ExecuteReader();
            dtUser.Load(sqlDR);
            sqlConn.Close();

            BGAssetService.Service1Client serviceAsset = new BGAssetService.Service1Client();
            serviceAsset.GetLoginDetails(username);            

            return dtUser;
            
        }