Form style / continents

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src/JobsJobsJobs/Server/Data/ContinentExtensions.cs

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+using JobsJobsJobs.Shared;
+using Npgsql;
+using System.Collections.Generic;
+using System.Threading.Tasks;
+
+namespace JobsJobsJobs.Server.Data
+{
+    /// <summary>
+    /// Data extensions for manipulation of continent objects
+    /// </summary>
+    public static class ContinentExtensions
+    {
+        /// <summary>
+        /// Create a continent from the current row in the data reader
+        /// </summary>
+        /// <param name="rdr">The data reader</param>
+        /// <returns>The current row's values as a continent object</returns>
+        private static Continent ToContinent(NpgsqlDataReader rdr) =>
+            new Continent(ContinentId.Parse(rdr.GetString("id")), rdr.GetString("name"));
+
+        /// <summary>
+        /// Retrieve all continents
+        /// </summary>
+        /// <returns>All continents</returns>
+        public static async Task<IEnumerable<Continent>> AllContinents(this NpgsqlConnection conn)
+        {
+            using var cmd = conn.CreateCommand();
+            cmd.CommandText = "SELECT * FROM continent ORDER BY name";
+
+            using var rdr = await cmd.ExecuteReaderAsync().ConfigureAwait(false);
+            var continents = new List<Continent>();
+            while (await rdr.ReadAsync())
+            {
+                continents.Add(ToContinent(rdr));
+            }
+
+            return continents;
+        }
+    }
+}