Add items to comboBox in WPF

Question

When I have added a comboBox to the WPF window, how do I add items to the comboBox? Int the XAML code for the design or in NameOfWindow.xaml.cs file?

Answer 1

CASE 1 - You don't have a data-source:

You can just populate the ComboBox with static values as follows -

1. from XAML:

<ComboBox Height="23" Name="comboBox1" Width="120">     <ComboBoxItem Content="Alice"/>     <ComboBoxItem Content="Bob"/>     <ComboBoxItem Content="Charlie"/> </ComboBox> 

2. from CodeBehind - 1:

private void Window_Loaded(object sender, RoutedEventArgs e) {     comboBox1.Items.Add("Alice");     comboBox1.Items.Add("Bob");     comboBox1.Items.Add("Charlie"); } 

3. from CodeBehind - 2:

// insert item at specified index of populated ComboBox private void Window_Loaded(object sender, RoutedEventArgs e) {     comboBox1.Items.Insert(2, "Alice");     comboBox1.Items.Insert(5, "Bob");     comboBox1.Items.Insert(8, "Charlie"); } 

CASE 2 - You have a data-source, and the items never get changed:

You can use the data-source to populate the ComboBox. Any IEnumerable type can be used as a data-source. You can -

1. bind the ItemsSource property in XAML to the data-source like -

<!-- MyDataSource is an IEnumerable type property in ViewModel --> <ComboBox Height="23" Width="120" ItemsSource="{Binding MyDataSource}" /> 

2. assign data-source to the ItemsSource property in the code-behind, like -

private void Window_Loaded(object sender, RoutedEventArgs e) {     comboBox1.ItemsSource = new List<string> { "Alice", "Bob", "Charlie" }; } 

CASE 3 - You have a data-source, and the items might get changed

1. You should use an ObservableCollection<T> as the data-source
2. You should bind the ItemsSource property in XAML to the data-source (as shown above)
3. You can assign data-source to the ItemsSource property in the code-behind (as shown above)

Using an ObservableCollection<T> ensures that whenever an item is added to or removed from the data-source, the change will reflect immediately on the UI. It's up to you how you populate the ObservableCollection<T>.