Reworked catalog project business logic with OOP, data binding and event handling in mind

3 files changed, 45 insertions, 58 deletions

diff --git a/VB.Net Projects/catalog/catalog/Form1.Designer.vb b/VB.Net Projects/catalog/catalog/Form1.Designer.vb
index 7337d03..6a85880 100644
--- a/VB.Net Projects/catalog/catalog/Form1.Designer.vb
+++ b/VB.Net Projects/catalog/catalog/Form1.Designer.vb
@@ -35,6 +35,7 @@ Partial Class Form1
         '

         'cbProducts

         '

+        Me.cbProducts.DropDownStyle = System.Windows.Forms.ComboBoxStyle.DropDownList

         Me.cbProducts.FormattingEnabled = True

         Me.cbProducts.Location = New System.Drawing.Point(17, 53)

         Me.cbProducts.Name = "cbProducts"

@@ -64,9 +65,9 @@ Partial Class Form1
         Me.lblProductPrice.AutoSize = True

         Me.lblProductPrice.Location = New System.Drawing.Point(210, 94)

         Me.lblProductPrice.Name = "lblProductPrice"

-        Me.lblProductPrice.Size = New System.Drawing.Size(32, 15)

+        Me.lblProductPrice.Size = New System.Drawing.Size(27, 15)

         Me.lblProductPrice.TabIndex = 3

-        Me.lblProductPrice.Text = "0 лв."

+        Me.lblProductPrice.Text = "ERR"

         '

         'btnAddProduct

         '

@@ -109,9 +110,9 @@ Partial Class Form1
         Me.lblSum.AutoSize = True

         Me.lblSum.Location = New System.Drawing.Point(141, 245)

         Me.lblSum.Name = "lblSum"

-        Me.lblSum.Size = New System.Drawing.Size(32, 15)

+        Me.lblSum.Size = New System.Drawing.Size(27, 15)

         Me.lblSum.TabIndex = 8

-        Me.lblSum.Text = "0 лв."

+        Me.lblSum.Text = "ERR"

         '

         'Form1

         '

diff --git a/VB.Net Projects/catalog/catalog/Form1.vb b/VB.Net Projects/catalog/catalog/Form1.vb
index 71af62b..a7329ae 100644
--- a/VB.Net Projects/catalog/catalog/Form1.vb
+++ b/VB.Net Projects/catalog/catalog/Form1.vb
@@ -1,65 +1,38 @@
-Public Class Form1

-    Dim Sum As Double

-    Dim Products As String() = {

-        "Магнитни наколенки",

-        "Магнитен колан",

-        "Магни Иър",

-        "Масажираща седалка",

-        "Сауна за лице",

-        "Електрическо одеяло",

-        "Инфраред масажор за тяло",

-        "Гривна за баланс",

-        "Цитрус джусер",

-        "Апарат за кръвно налягане"

+Imports System.ComponentModel

+

+Public Class Form1

+    ReadOnly Products As BindingList(Of Product) = New BindingList(Of Product) From {

+        New Product("Магнитни наколенки", 59.9),

+        New Product("Магнитен колан", 39.9),

+        New Product("Магни Иър", 39.9),

+        New Product("Масажираща седалка", 59.9),

+        New Product("Сауна за лице", 49.9),

+        New Product("Електрическо одеяло", 56.9),

+        New Product("Инфраред масажор за тяло", 147.0),

+        New Product("Гривна за баланс", 54.9),

+        New Product("Цитрус джусер", 49.9),

+        New Product("Апарат за кръвно налягане", 109.8)

     }

-    Dim Prices As Single() = {

-        59.9,

-        39.9,

-        39.9,

-        59.9,

-        49.9,

-        56.9,

-        147.0,

-        54.9,

-        49.9,

-        109.8

-    }

-

-    Private Function ToCurrency(Optional value As Double = 0) As String

-        Return FormatCurrency(value, 2)

-    End Function

+    ReadOnly ChosenProducts As BindingList(Of Product) = New BindingList(Of Product)

 

     Private Sub Form_Load(sender As Object, e As EventArgs) Handles MyBase.Load

-        cbProducts.Items.AddRange(Products)

-        lblSum.Text = ToCurrency()

-        lblProductPrice.Text = ToCurrency()

+        cbProducts.DataSource = Products

+        lbChosenProducts.DataSource = ChosenProducts

     End Sub

 

-    Private Sub cbProducts_SelectedIndexChanged(sender As Object, e As EventArgs) Handles cbProducts.SelectedIndexChanged

-        lblProductPrice.Text = ToCurrency(Prices(cbProducts.SelectedIndex))

-    End Sub

-

-    Private Sub btnAddProduct_Click(sender As Object, e As EventArgs) Handles btnAddProduct.Click

-        If String.IsNullOrEmpty(cbProducts.Text) Then

-            Return

+    Private Sub UpdateChosenProducts(sender As Object, e As EventArgs) Handles btnAddProduct.Click, btnRemoveProduct.Click

+        If DirectCast(sender, Control).Name = btnAddProduct.Name Then

+            ChosenProducts.Add(Products(cbProducts.SelectedIndex))

+        Else

+            ChosenProducts.Remove(cbProducts.SelectedItem)

         End If

-

-        lbChosenProducts.Items.Add(cbProducts.Text)

-        Sum += Prices(cbProducts.SelectedIndex)

-        lblSum.Text = ToCurrency(Sum)

     End Sub

 

-    Private Sub btnRemoveProduct_Click(sender As Object, e As EventArgs) Handles btnRemoveProduct.Click

-        If String.IsNullOrEmpty(cbProducts.Text) Then

-            Return

-        End If

-

-        If Not lbChosenProducts.Items.Contains(cbProducts.SelectedItem) Then

-            Return

-        End If

+    Private Sub UpdateSumLabel(sender As Object, e As EventArgs) Handles btnAddProduct.Click, btnRemoveProduct.Click, MyBase.Load

+        lblSum.Text = FormatCurrency(ChosenProducts.Sum(Function(p) p.Price), 2)

+    End Sub

 

-        lbChosenProducts.Items.Remove(cbProducts.SelectedItem)

-        Sum -= Prices(cbProducts.SelectedIndex)

-        lblSum.Text = ToCurrency(Sum)

+    Private Sub cbProducts_SelectedIndexChanged(sender As Object, e As EventArgs) Handles cbProducts.SelectedIndexChanged, MyBase.Load

+        lblProductPrice.Text = FormatCurrency(Products(cbProducts.SelectedIndex).Price, 2)

     End Sub

 End Class
\ No newline at end of file
diff --git a/VB.Net Projects/catalog/catalog/Product.vb b/VB.Net Projects/catalog/catalog/Product.vb
new file mode 100644
index 0000000..a9c4fe5
--- /dev/null
+++ b/VB.Net Projects/catalog/catalog/Product.vb
@@ -0,0 +1,13 @@
+Public Class Product

+    Public Name As String

+    Public Price As Single

+

+    Public Sub New(name As String, price As Single)

+        Me.Name = name

+        Me.Price = price

+    End Sub

+

+    Public Overrides Function ToString() As String

+        Return Me.Name

+    End Function

+End Class
\ No newline at end of file