A simple Web Service for the beginners; ASP.Net C#

WebService Method in App Code folder with a [WebMethod] attribute. Just a normal C# method with [WebMethod] attribute. @RecordCount is an output parameter returned by the stored procedure.

     [WebMethod]
    public static Int64 VerifyDuplicateActivation(Int64 DetailsId)
    {
        Int64 RecordsCount = 0;
        string connString = ConfigurationManager.AppSettings["DatabaseAnalyzeUAT1"].ToString();
        SqlConnection oConn = new SqlConnection(connString);
        SqlCommand oCommand = new SqlCommand();
        oCommand.Connection = oConn;
        oCommand.CommandText = "VerifyTeamActivation";
        oCommand.CommandType = CommandType.StoredProcedure;
        oCommand.Parameters.AddWithValue("@DetailsID", DetailsId);
        oCommand.Parameters.Add("@RecordCount", SqlDbType.BigInt);
        oCommand.Parameters["@RecordCount"].Direction = ParameterDirection.Output;
        oConn.Open();
        oCommand.ExecuteScalar();
        RecordsCount = (Int64)oCommand.Parameters["@RecordCount"].Value;
        return RecordsCount;
    }

Consuming WebService is just a method call if it is from Server Side.

Int64 RecCount = VerifyForDuplicate(details.DetailsId);