LP4 M4 updated instructions, starter code, and solution code

Author: ChrisHowd

DownloadableCodeProjects/LP4_manage-app-data/Data_M4/Solution/Bank.cs

@@ -47,18 +47,15 @@ public BankAccountNumber(string value)
 
 public record AccountHolderDetails(string Name, string CustomerId, string Address);
 
-// TODO: Task 6: Step 3 - Add the DailyTotal record near the record/type definitions.
-public record DailyTotal(DateOnly Day, decimal Total, int Count);
-
-// TODO: Task 4: Step 1 - Add the ILedgerEntry interface near the record/type definitions.
+// Task 4: Step 1 - Add the ILedgerEntry interface near the record/type definitions.
 public interface ILedgerEntry
 {
     decimal Amount { get; }
     DateTime Date { get; }
     string Description { get; }
 }
 
-// TODO: Task 4: Step 2 - Update Transaction to implement ILedgerEntry.
+// Task 4: Step 2 - Update Transaction to implement ILedgerEntry.
 public record Transaction(decimal Amount, DateTime Date, string Description) : ILedgerEntry
 {
     public override string ToString()
@@ -67,24 +64,8 @@ public override string ToString()
     }
 }
 
-// TODO: Task 4: Step 3 - Add the generic Ledger<TEntry> class (where TEntry : ILedgerEntry).
-public sealed class Ledger<TEntry> where TEntry : ILedgerEntry
-{
-    private readonly List<TEntry> _entries = new();
-
-    public IReadOnlyList<TEntry> Entries => _entries;
-
-    public void Add(TEntry entry)
-    {
-        if (entry is null) throw new ArgumentNullException(nameof(entry));
-        _entries.Add(entry);
-    }
-
-    public decimal Total() => _entries.Sum(e => e.Amount);
-}
-
-// TODO: Task 4: Step 8 - Add a second ledger entry type (e.g., Fee) that implements ILedgerEntry.
-public record Fee(decimal Amount, DateTime Date, string Description) : ILedgerEntry;
+// Task 6: Step 1 - Add the DailyTotal record near the record/type definitions.
+public record DailyTotal(DateOnly Day, decimal Total, int Count);
 
 public class BankAccount
 {
@@ -93,13 +74,11 @@ public class BankAccount
     public decimal Balance { get; private set; }
     public AccountHolderDetails AccountHolder { get; }
 
-    // TODO: Task 2: Step 1 - Replace the transactions collection with a private backing field.
-    // TODO: Task 2: Step 3 - Expose transactions as a read-only generic view (IReadOnlyList<Transaction>).
-    // TODO: Task 4: Step 5 - Refactor BankAccount to store transactions in Ledger<Transaction>.
+    // Task 4: Step 4 - Refactor BankAccount to store transactions in Ledger<Transaction>.
     private readonly Ledger<Transaction> _ledger = new();
-
     public IReadOnlyList<Transaction> Transactions => _ledger.Entries;
 
+
     public BankAccount(BankAccountNumber accountNumber, BankAccountType accountType, AccountHolderDetails accountHolder, decimal initialBalance = 0)
     {
         AccountNumber = accountNumber;
@@ -110,9 +89,8 @@ public BankAccount(BankAccountNumber accountNumber, BankAccountType accountType,
 
     public void AddTransaction(decimal amount, string description)
     {
-        // TODO: Task 2: Step 4 - Update AddTransaction to add to the backing field.
-        // TODO: Task 4: Step 6 - Update AddTransaction to call _ledger.Add(...) once Ledger<Transaction> is introduced.
 
+        // Task 4: Step 5 - Update AddTransaction to call _ledger.Add(...) once Ledger<Transaction> is introduced.
         Balance += amount;
         _ledger.Add(new Transaction(amount, DateTime.Now, description));
     }
@@ -124,20 +102,21 @@ public string DisplayAccountInfo()
 
     public void DisplayTransactions()
     {
-        // TODO: Task 2: Step 5 - Update DisplayTransactions to iterate the public read-only Transactions view.
-        // TODO: Task 4: Step 7 - Ensure display iterates _ledger.Entries (or the Transactions view backed by it).
-
         Console.WriteLine("Transactions:");
+
+        // Task 4: Step 6 - Ensure display iterates _ledger.Entries (or the Transactions view backed by it).
+        // Task 2: Step 4 - Update DisplayTransactions to iterate the public read-only Transactions view.
         foreach (var transaction in Transactions)
         {
             Console.WriteLine(transaction);
         }
     }
 
-    // TODO: Task 2: Step 6 - (Optional) Add GetTransactions() returning IEnumerable<Transaction>.
+    // Task 2: Step 5 - Add GetTransactions() returning IEnumerable<Transaction>.
     public IEnumerable<Transaction> GetTransactions() => Transactions;
 
-    // TODO: Task 6: Step 4 - Add GetDailyTotals() returning IEnumerable<DailyTotal>.
+
+    // Task 6: Step 2 - Add GetDailyTotals() returning IEnumerable<DailyTotal>.
     public IEnumerable<DailyTotal> GetDailyTotals()
     {
         return Transactions
@@ -148,8 +127,7 @@ public IEnumerable<DailyTotal> GetDailyTotals()
 
 }
 
-// TODO: Task 3: Step 1 - Add the Bank class that stores accounts in Dictionary<BankAccountNumber, BankAccount>.
-
+// Task 3: Step 1 - Add the Bank class that stores accounts in Dictionary<BankAccountNumber, BankAccount>.
 public sealed class Bank
 {
     private readonly Dictionary<BankAccountNumber, BankAccount> _accounts = new();
@@ -175,7 +153,21 @@ public bool CloseAccount(BankAccountNumber number)
         => _accounts.Remove(number);
 }
 
-// TODO: Task 4: Step 3 - Add the generic Ledger<TEntry> class (where TEntry : ILedgerEntry).
+// Task 4: Step 3 - Add the generic Ledger<TEntry> class (where TEntry : ILedgerEntry).
+public sealed class Ledger<TEntry> where TEntry : ILedgerEntry
+{
+    private readonly List<TEntry> _entries = new();
 
-// TODO: Task 4: Step 8 - Add a second ledger entry type (e.g., Fee) that implements ILedgerEntry.
+    public IReadOnlyList<TEntry> Entries => _entries;
 
+    public void Add(TEntry entry)
+    {
+        if (entry is null) throw new ArgumentNullException(nameof(entry));
+        _entries.Add(entry);
+    }
+
+    public decimal Total() => _entries.Sum(e => e.Amount);
+}
+
+// Task 4: Step 7 - Add a second ledger entry type (e.g., Fee) that implements ILedgerEntry.
+public record Fee(decimal Amount, DateTime Date, string Description) : ILedgerEntry;

DownloadableCodeProjects/LP4_manage-app-data/Data_M4/Solution/Program.cs

@@ -9,34 +9,41 @@ static void Main(string[] args)
     {
         Console.WriteLine("Welcome to the Bank App!");
 
-        // TODO: Task 3: Step 3 - Update Program to create a Bank and open 2–3 accounts.
-
+        // Task 3: Step 2 - Update Program to create a Bank and open 2 accounts.
         var bank = new Bank();
 
-        var holder1 = new AccountHolderDetails("Tim Shao", "123456789", "123 Elm Street");
-        var number1 = new BankAccountNumber("000012345678");
-        var checking = new BankAccount(number1, BankAccountType.Checking, holder1, 500m);
-        bank.OpenAccount(checking);
+        var accountHolderDetails = new AccountHolderDetails("Tim Shao", "123456789", "123 Elm Street");
+        var accountNumber = new BankAccountNumber("000012345678");
+        var checking = new BankAccount(accountNumber, BankAccountType.Checking, accountHolderDetails, 500m);
+
+        var accountHolderDetails3 = new AccountHolderDetails("Ni Kang", "987654321", "456 Oak Avenue");
+        var accountNumber3 = new BankAccountNumber("000123456789");
+        var savings = new BankAccount(accountNumber3, BankAccountType.Savings, accountHolderDetails3, 1200m);
 
-        var holder2 = new AccountHolderDetails("Ava Patel", "987654321", "456 Oak Avenue");
-        var number2 = new BankAccountNumber("000123456789");
-        var savings = new BankAccount(number2, BankAccountType.Savings, holder2, 1200m);
+        bank.OpenAccount(checking);
         bank.OpenAccount(savings);
 
         // Keep a reference named `bankAccount` for the reporting tasks later in this lab.
         var bankAccount = checking;
 
-        Console.WriteLine("\nTASK 4: Display basic bank account information");
+        // Task 3: Step 3 - Retrieve account and perform transactions.
+        var selected = bank.GetAccount(accountNumber);
+        selected.AddTransaction(200m, "Deposit");
+        selected.AddTransaction(-50m, "ATM Withdrawal");
+        Console.WriteLine(selected.DisplayAccountInfo());
+
         Console.WriteLine($"Account type description: {bankAccount.AccountType.GetDescription()}");
         Console.WriteLine(bankAccount.DisplayAccountInfo());
 
         bankAccount.AddTransaction(200m, "Deposit");
         bankAccount.AddTransaction(-50m, "ATM Withdrawal");
 
+        // Task 4: Step 8 - Add Fee transactions to the account.
         var feeLedger = new Ledger<Fee>();
         feeLedger.Add(new Fee(-2.50m, DateTime.Now, "Monthly service fee"));
         Console.WriteLine($"Fee ledger total: {feeLedger.Total():C}");
 
+        // Task 5: Step 1 - Add an anonymous-type transaction report (Select(...) into new { ... }).
         var rows = bankAccount.Transactions
             .Select(t => new
             {
@@ -52,12 +59,15 @@ static void Main(string[] args)
             Console.WriteLine($"{row.Date:d} | {row.Kind,-6} | {row.Amount,10:C} | {row.Description}");
         }
 
+
+        // Task 6: Step 3 - Update Program to call bankAccount.GetDailyTotals() (named record) for API-friendly reporting.
         Console.WriteLine("Daily totals:");
         foreach (var day in bankAccount.GetDailyTotals())
         {
             Console.WriteLine($"{day.Day}: {day.Total:C} ({day.Count} tx)");
         }
 
+        // Task 5: Step 3 - Add an anonymous-type "top debits" report (Where/OrderBy/Take).
         var topDebits = bankAccount.Transactions
             .Where(t => t.Amount < 0)
             .OrderBy(t => t.Amount)
@@ -70,22 +80,13 @@ static void Main(string[] args)
             Console.WriteLine($"{d.Date:d} | {d.Amount,10:C} | {d.Description}");
         }
 
-        // TODO: Task 5: Step 3 - Add an anonymous-type transaction report (Select(...) into new { ... }).
-
-        // TODO: Task 5: Step 5 - Add an anonymous-type daily totals report (GroupBy(...) + Select(...)).
-
-        // TODO: Task 5: Step 7 - Add an anonymous-type "top debits" report (Where/OrderBy/Take).
-
-        // TODO: Task 6: Step 5 - Update Program to call bankAccount.GetDailyTotals() (named record) for API-friendly reporting.
 
-        Console.WriteLine("\nTASK 5: Demonstrate using the Transaction record");
         Console.WriteLine(bankAccount.DisplayAccountInfo());
         bankAccount.DisplayTransactions();
 
-        AccountHolderDetails customer2 = new("Tim Shao", "123456789", "123 Elm Street");
+        AccountHolderDetails accountHolderDetails2 = new("Tim Shao", "123456789", "123 Elm Street");
 
-        Console.WriteLine("\nTASK 6: Demonstrate record comparison and struct immutability");
-        Console.WriteLine($"Are customers equal? {holder1 == customer2}");
+        Console.WriteLine($"Are customers equal? {accountHolderDetails == accountHolderDetails2}");
 
         BankAccountNumber accountNumber2 = new BankAccountNumber("000123456789");
         Console.WriteLine($"Original Account Number: {accountNumber2}");

DownloadableCodeProjects/LP4_manage-app-data/Data_M4/Starter/Bank.cs

@@ -39,9 +39,10 @@ public BankAccountNumber(string value)
 
 public record AccountHolderDetails(string Name, string CustomerId, string Address);
 
-// TODO: Task 4: Step 1 - Add the ILedgerEntry interface near the record/type definitions.
+// Task 4: Step 1 - Add the ILedgerEntry interface near the record/type definitions.
 
-// TODO: Task 4: Step 2 - Update Transaction to implement ILedgerEntry.
+
+// Task 4: Step 2 - Update Transaction to implement ILedgerEntry.
 public record Transaction(decimal Amount, DateTime Date, string Description)
 {
     public override string ToString()
@@ -50,19 +51,22 @@ public override string ToString()
     }
 }
 
+// Task 6: Step 1 - Add the DailyTotal record near the record/type definitions.
+
+
 public class BankAccount
 {
     public BankAccountNumber AccountNumber { get; }
     public BankAccountType AccountType { get; }
     public decimal Balance { get; private set; }
     public AccountHolderDetails AccountHolder { get; }
 
-    // TODO: Task 2: Step 2 - Replace the transactions collection with a private backing field.
+    // Task 4: Step 4 - Refactor BankAccount to store transactions in Ledger<Transaction>.
+    // Task 2: Step 1 - Replace the transactions collection with a private backing field.
+    private List<Transaction> Transactions { get; } = new();
 
-    // TODO: Task 2: Step 3 - Expose transactions as a read-only generic view (IReadOnlyList<Transaction>).
+    // Task 2: Step 2 - Expose transactions as a read-only generic view (IReadOnlyList<Transaction>).
 
-    // TODO: Task 4: Step 5 - Refactor BankAccount to store transactions in Ledger<Transaction>.
-    private List<Transaction> Transactions { get; } = new();
 
     public BankAccount(BankAccountNumber accountNumber, BankAccountType accountType, AccountHolderDetails accountHolder, decimal initialBalance = 0)
     {
@@ -74,11 +78,11 @@ public BankAccount(BankAccountNumber accountNumber, BankAccountType accountType,
 
     public void AddTransaction(decimal amount, string description)
     {
-        // TODO: Task 2: Step 4 - Update AddTransaction to add to the backing field.
-
-        // TODO: Task 4: Step 6 - Update AddTransaction to call _ledger.Add(...) once Ledger<Transaction> is introduced.
 
+        // Task 4: Step 5 - Update AddTransaction to call _ledger.Add(...) once Ledger<Transaction> is introduced.
         Balance += amount;
+
+        // Task 2: Step 3 - Update AddTransaction to add to the backing field.
         Transactions.Add(new Transaction(amount, DateTime.Now, description));
     }
 
@@ -89,27 +93,28 @@ public string DisplayAccountInfo()
 
     public void DisplayTransactions()
     {
-        // TODO: Task 2: Step 5 - Update DisplayTransactions to iterate the public read-only Transactions view.
-
-        // TODO: Task 4: Step 7 - Ensure display iterates _ledger.Entries (or the Transactions view backed by it).
-
         Console.WriteLine("Transactions:");
-        foreach (var transaction in Transactions)
+
+        // Task 4: Step 6 - Ensure display iterates _ledger.Entries (or the Transactions view backed by it).
+        // Task 2: Step 4 - Update DisplayTransactions to iterate the public read-only Transactions view.
+        foreach (Transaction transaction in Transactions)
         {
             Console.WriteLine(transaction);
         }
     }
 
-    // TODO: Task 2: Step 6 - (Optional) Add GetTransactions() returning IEnumerable<Transaction>.
+    // Task 2: Step 5 - Add GetTransactions() returning IEnumerable<Transaction>.
+
+
+    // Task 6: Step 2 - Add GetDailyTotals() returning IEnumerable<DailyTotal>.
 
-    // TODO: Task 6: Step 4 - Add GetDailyTotals() returning IEnumerable<DailyTotal>.
 
 }
 
-// TODO: Task 3: Step 1 - Add the Bank class that stores accounts in Dictionary<BankAccountNumber, BankAccount>.
+// Task 3: Step 1 - Add the Bank class that stores accounts in Dictionary<BankAccountNumber, BankAccount>.
+
 
-// TODO: Task 4: Step 3 - Add the generic Ledger<TEntry> class (where TEntry : ILedgerEntry).
+// Task 4: Step 3 - Add the generic Ledger<TEntry> class (where TEntry : ILedgerEntry).
 
-// TODO: Task 4: Step 8 - Add a second ledger entry type (e.g., Fee) that implements ILedgerEntry.
 
-// TODO: Task 6: Step 3 - Add the DailyTotal record near the record/type definitions.
+// Task 4: Step 7 - Add a second ledger entry type (e.g., Fee) that implements ILedgerEntry.

DownloadableCodeProjects/LP4_manage-app-data/Data_M4/Starter/Program.cs

@@ -9,33 +9,41 @@ static void Main(string[] args)
     {
         Console.WriteLine("Welcome to the Bank App!");
 
-        // TODO: Task 3: Step 3 - Update Program to create a Bank and open 2–3 accounts.
-
+        // Task 3: Step 2 - Update Program to create a Bank and open 2 accounts.
         AccountHolderDetails accountHolderDetails = new("Tim Shao", "123456789", "123 Elm Street");
         BankAccountNumber accountNumber = new BankAccountNumber("000012345678");
-
         BankAccount bankAccount = new(accountNumber, BankAccountType.Checking, accountHolderDetails, 500m);
 
+        // Task 3: Step 3 - Retrieve account and perform transactions.
+
+
         Console.WriteLine($"Account type description: {bankAccount.AccountType.GetDescription()}");
         Console.WriteLine(bankAccount.DisplayAccountInfo());
 
         bankAccount.AddTransaction(200m, "Deposit");
         bankAccount.AddTransaction(-50m, "ATM Withdrawal");
 
-        // TODO: Task 5: Step 3 - Add an anonymous-type transaction report (Select(...) into new { ... }).
+        // Task 5: Step 3 - Add an anonymous-type transaction report (Select(...) into new { ... }).
+
 
-        // TODO: Task 5: Step 5 - Add an anonymous-type daily totals report (GroupBy(...) + Select(...)).
+        // Task 5: Step 5 - Add an anonymous-type daily totals report (GroupBy(...) + Select(...)).
 
-        // TODO: Task 5: Step 7 - Add an anonymous-type "top debits" report (Where/OrderBy/Take).
 
-        // TODO: Task 6: Step 5 - Update Program to call bankAccount.GetDailyTotals() (named record) for API-friendly reporting.
+        // Task 5: Step 7 - Add an anonymous-type "top debits" report (Where/OrderBy/Take).
+
+
+        // Task 6: Step 3 - Update Program to call bankAccount.GetDailyTotals() (named record) for API-friendly reporting.
+
 
         Console.WriteLine(bankAccount.DisplayAccountInfo());
         bankAccount.DisplayTransactions();
 
-        AccountHolderDetails customer2 = new("Tim Shao", "123456789", "123 Elm Street");
+        // Task 4: Step 8 - Add Fee transactions to the account.
+
+
+        AccountHolderDetails accountHolderDetails2 = new("Tim Shao", "123456789", "123 Elm Street");
 
-        Console.WriteLine($"Are customers equal? {accountHolderDetails == customer2}");
+        Console.WriteLine($"Are customers equal? {accountHolderDetails == accountHolderDetails2}");
 
         BankAccountNumber accountNumber2 = new BankAccountNumber("000123456789");
         Console.WriteLine($"Original Account Number: {accountNumber2}");