PI06 i PI06-1. Docker definitions for MSSQL and Postgres. Data seeder/generator for countries and people. Entity Framework example with variants for Postgres and MSSQL

SomeOfCSharpFeatures/Extensions/Activity.cs

@@ -0,0 +1,16 @@
+using System;
+
+namespace Extensions;
+
+[Flags]
+public enum DayPeriod
+{
+  Morning = 1, Evening = 2, Afternoon = 4, Night = 8
+}
+
+public class Activity
+{
+  public required string Person { get; set; }
+  public int Hours { get; set; }
+  public DayPeriod Period { get; set; }
+}

SomeOfCSharpFeatures/Extensions/Extensions.cs

@@ -0,0 +1,18 @@
+using System.Collections.Generic;
+
+namespace Extensions;
+
+public static class Extensions
+{
+  public static V GetOrCreate<K, V>(this Dictionary<K, V> dict, K key) 
+    where V : new()
+    where K: notnull  
+  {
+    if (!dict.TryGetValue(key, out V? value))
+    {
+      value = new V();
+      dict[key] = value;        
+    }
+    return value;            
+  }
+}

SomeOfCSharpFeatures/Extensions/Extensions.csproj

@@ -0,0 +1,10 @@
+<Project Sdk="Microsoft.NET.Sdk">
+
+  <PropertyGroup>
+    <OutputType>Exe</OutputType>
+    <TargetFramework>net10.0</TargetFramework>
+    <ImplicitUsings>enable</ImplicitUsings>
+    <Nullable>enable</Nullable>
+  </PropertyGroup>
+
+</Project>

SomeOfCSharpFeatures/Extensions/Program.cs

@@ -0,0 +1,61 @@
+namespace Extensions;
+
+public enum Days
+{
+  Monday, Tuesday, Wednesday,
+  Thursday, Friday, Saturday, Sunday
+}
+
+class Program
+{    
+  static void Main(string[] args)
+  {
+    var dict = new Dictionary<Days, List<Activity>>();
+    Activity a = new Activity
+    {
+      Person = "John",
+      Hours = 3,
+      Period = DayPeriod.Morning
+    };
+    dict.GetOrCreate(Days.Monday).Add(a);
+
+    a = new Activity
+    {
+      Person = "Mary",
+      Hours = 12,
+      Period = DayPeriod.Evening | DayPeriod.Night
+    };
+    dict.GetOrCreate(Days.Monday).Add(a);
+
+    a = new Activity
+    {
+      Person = "Peter",
+      Hours = 8,
+      Period = DayPeriod.Night
+    };
+    dict.GetOrCreate(Days.Tuesday).Add(a);
+
+    a = new Activity
+    {
+      Person = "Lisa",
+      Hours = 5,
+      Period = DayPeriod.Night | DayPeriod.Morning
+    };
+    dict.GetOrCreate(Days.Monday).Add(a);
+
+    int sum = SumNightActivity(dict);
+    Console.WriteLine(sum);
+
+  }
+
+  private static int SumNightActivity(Dictionary<Days, List<Activity>> dict)
+  {
+    int sum = 0;
+    foreach(var list in dict.Values)
+    {
+      sum += list.Where(a => (a.Period & DayPeriod.Night) == DayPeriod.Night)
+                 .Sum(a => a.Hours);                   
+    }
+    return sum;  
+  }
+}