Introduced new GetReturnCode() extension method

Simple internal extension method for centralizing logic for retrieving the return code and making sure it's converted to an integer.

Author: JeremyCaney

OnTopic.Data.Sql/SqlCommandExtensions.cs

@@ -5,6 +5,7 @@
 \=============================================================================================================================*/
 using System;
 using System.Data;
+using System.Globalization;
 using System.Text;
 using Microsoft.Data.SqlClient;
 using OnTopic.Internal.Diagnostics;
@@ -19,6 +20,22 @@ namespace OnTopic.Data.Sql {
   /// </summary>
   internal static class SqlCommandExtensions {
 
+    /*==========================================================================================================================
+    | METHOD: GET RETURN CODE
+    \-------------------------------------------------------------------------------------------------------------------------*/
+    /// <summary>
+    ///   Retrieves the return code from a stored procedure.
+    /// </summary>
+    /// <param name="command">The SQL command object.</param>
+    internal static int GetReturnCode(this SqlCommand command, string sqlParameter = "ReturnCode") {
+      Contract.Assume<InvalidOperationException>(
+        command.Parameters.Contains($"@{sqlParameter}"),
+        $"The call to the {command.CommandText} stored procedure did not return the expected 'ReturnCode' parameter."
+      );
+      var returnCode = command.Parameters[$"@{sqlParameter}"].Value.ToString();
+      return Int32.Parse(returnCode, CultureInfo.InvariantCulture);
+    }
+
     /*==========================================================================================================================
     | METHOD: ADD OUTPUT PARAMETER
     \-------------------------------------------------------------------------------------------------------------------------*/

OnTopic.Data.Sql/SqlTopicRepository.cs

@@ -349,11 +349,7 @@ public override Topic Load(string? topicKey = null, bool isRecursive = true) {
         /*----------------------------------------------------------------------------------------------------------------------
         | Process return value
         \---------------------------------------------------------------------------------------------------------------------*/
-        Contract.Assume<InvalidOperationException>(
-          command.Parameters["@ReturnCode"] != null,
-          "The call to the GetTopicID stored procedure did not return the expected 'ReturnCode' parameter."
-        );
-        topicId                 = Int32.Parse(command.Parameters["@ReturnCode"].Value.ToString(), CultureInfo.InvariantCulture);
+        topicId                 = command.GetReturnCode();
 
       }
 
@@ -777,13 +773,7 @@ public override int Save([NotNull]Topic topic, bool isRecursive = false, bool is
         /*----------------------------------------------------------------------------------------------------------------------
         | Process return value
         \---------------------------------------------------------------------------------------------------------------------*/
-        Contract.Assume<InvalidOperationException>(
-          command.Parameters["@ReturnCode"] != null,
-          "The call to the CreateTopic stored procedure did not return the expected 'ReturnCode' parameter."
-        );
-        returnVal               = Int32.Parse(command.Parameters["@ReturnCode"].Value.ToString(), CultureInfo.InvariantCulture);
-
-        topic.Id                = returnVal;
+        topic.Id                = command.GetReturnCode();
 
         Contract.Assume<InvalidOperationException>(
           topic.Id > 0,