Merge pull request #1123 from syncfusion-content/Prepare-UG-document-for-the-events-fired-hotfix

WF-875216 : Prepare UG document for the events fired when selecting/unselecting Tokens in SfComboBox control

Author: Manivannan-E

WindowsForms/ComboBox/Token.md

@@ -62,3 +62,134 @@ sfComboBox1.Style.TokenStyle.Font = New Font(“Arial”, 10F, FontStyle.Bold)
 * Using the <kbd>Down Arrow</kbd>, <kbd>Up Arrow</kbd>, and <kbd>Enter</kbd> keys, item can be selected from the combobox.
 * Using the <kbd>Backspace</kbd> key, the last positioned token will be removed from the text area.
 * When the <kbd>Esc</kbd> key is pressed, the drop-down area will be closed if it has been opened already. 
+
+## Events Fired When Selecting and Deselecting Tokens 
+
+The [SelectedValueChanged](https://help.syncfusion.com/cr/windowsforms/Syncfusion.WinForms.ListView.SfComboBox.html#Syncfusion_WinForms_ListView_SfComboBox_SelectedValueChanged) event is triggered whenever tokens are selected or deselected in the SfComboBox control. This allows users to handle changes in token selections effectively.
+
+{% tabs %}
+{% highlight c# %}
+
+private List<object> _previousSelectedTokens; 
+private Label label;  
+
+SfComboBox sfComboBox1 = new SfComboBox
+{
+    EnableToken = true,
+    DisplayMember = "Name",
+    ValueMember = "Id",
+    Size = new Size(300, 30),
+    DataSource = new List<dynamic>
+   {
+    new { Id = 1, Name = "Item1" },
+    new { Id = 2, Name = "Item2" },
+    new { Id = 3, Name = "Item3" }
+   }
+};
+
+sfComboBox1.Style.TokenStyle.Font = new Font("Arial", 9.75F, FontStyle.Regular, GraphicsUnit.Point);
+
+// Initialize Label
+label = new Label
+{
+    Width = 200,
+    Location = new Point(10, 110)
+};
+
+// Initialize selected items and previous tokens
+sfComboBox1.SelectedItems.Add(sfComboBox1.DropDownListView.View.DisplayItems[0]);
+_previousSelectedTokens = sfComboBox1.SelectedItems.Cast<dynamic>().ToList();
+
+sfComboBox1.SelectedValueChanged += SfComboBox1_SelectedValueChanged;
+
+this.Controls.Add(sfComboBox1);
+this.Controls.Add(label);
+
+private void TokenComboBox_SelectedValueChanged(object sender, EventArgs e)
+{
+    var comboBox = sender as SfComboBox;
+
+    // Get current and previous tokens
+    var currentSelectedTokens = comboBox.SelectedItems.Cast<dynamic>().ToList();
+    var addedTokens = currentSelectedTokens.Except(_previousSelectedTokens).ToList();
+    var removedTokens = _previousSelectedTokens.Except(currentSelectedTokens).ToList();
+
+    // Update previous tokens
+    _previousSelectedTokens = currentSelectedTokens;
+
+    // Handle added tokens
+    foreach (var token in addedTokens)
+    {
+       label.Text = $"Token Added: {token.Name}";
+    }
+
+    // Handle removed tokens
+    foreach (var token in removedTokens)
+    {
+       label.Text = $"Token Removed: {token.Name}";
+    }
+}
+
+{% endhighlight %}
+{% highlight vb %}
+
+Private _previousSelectedTokens As List(Of Object)
+Private label As Label
+
+' Initialize SfComboBox
+Dim sfComboBox1 As New SfComboBox With {
+    .EnableToken = True,
+    .DisplayMember = "Name",
+    .ValueMember = "Id",
+    .Size = New Size(300, 30),
+    .DataSource = New List(Of Object) From {
+        New With {.Id = 1, .Name = "Item1"},
+        New With {.Id = 2, .Name = "Item2"},
+        New With {.Id = 3, .Name = "Item3"}
+    }
+}
+
+sfComboBox1.Style.TokenStyle.Font = New Font("Arial", 9.75F, FontStyle.Regular, GraphicsUnit.Point)
+
+' Initialize Label
+label = New Label With {
+    .Width = 200,
+    .Location = New Point(10, 110)
+}
+
+' Initialize selected items and previous tokens
+sfComboBox1.SelectedItems.Add(sfComboBox1.DropDownListView.View.DisplayItems(0))
+_previousSelectedTokens = sfComboBox1.SelectedItems.Cast(Of Object)().ToList()
+
+AddHandler sfComboBox1.SelectedValueChanged, AddressOf TokenComboBox_SelectedValueChanged
+
+Me.Controls.Add(sfComboBox1)
+Me.Controls.Add(label)
+
+
+Private Sub TokenComboBox_SelectedValueChanged(sender As Object, e As EventArgs)
+    Dim comboBox = TryCast(sender, SfComboBox)
+
+    ' Get current and previous tokens
+    Dim currentSelectedTokens = comboBox.SelectedItems.Cast(Of Object)().ToList()
+    Dim addedTokens = currentSelectedTokens.Except(_previousSelectedTokens).ToList()
+    Dim removedTokens = _previousSelectedTokens.Except(currentSelectedTokens).ToList()
+
+    ' Update previous tokens
+    _previousSelectedTokens = currentSelectedTokens
+
+    ' Handle added tokens
+    For Each token In addedTokens
+        label.Text = $"Token Added: {token.Name}"
+    Next
+
+   ' Handle removed tokens
+    For Each token In removedTokens
+        label.Text = $"Token Removed: {token.Name}"
+    Next
+End Sub
+
+{% endhighlight %}
+{% endtabs %}
+
+![Event Triggered on Token Selection or Deselection](Token_images/Token_Event.gif)