How to: Add and Remove Items from a Windows Forms ComboBox, ListBox, or CheckedListBox Control
Items can be added to a Windows Forms combo box, list box, or checked list box in a variety of ways, because these controls can be bound to a variety of data sources. However, this topic demonstrates the simplest method and requires no data binding. The items displayed are usually strings; however, any object can be used. The text that is displayed in the control is the value returned by the object'sToString
method.
To add items
Add the string or object to the list by using the Add method of the ObjectCollection class. The collection is referenced using the
Items
property:ComboBox1.Items.Add("Tokyo")
comboBox1.Items.Add("Tokyo");
comboBox1.get_Items().Add("Tokyo");
comboBox1->Items->Add("Tokyo");
- or -
Insert the string or object at the desired point in the list with the
Insert
method:CheckedListBox1.Items.Insert(0, "Copenhagen")
checkedListBox1.Items.Insert(0, "Copenhagen");
checkedListBox1.get_Items().Insert(0, "Copenhagen");
checkedListBox1->Items->Insert(0, "Copenhagen");
- or -
Assign an entire array to the
Items
collection:Dim ItemObject(9) As System.Object Dim i As Integer For i = 0 To 9 ItemObject(i) = "Item" & i Next i ListBox1.Items.AddRange(ItemObject)
System.Object[] ItemObject = new System.Object[10]; for (int i = 0; i <= 9; i++) { ItemObject[i] = "Item" + i; } listBox1.Items.AddRange(ItemObject);
System.Object[] ItemObject = new System.Object[10]; for(int i=0;i <= 9;i ++) { ItemObject .set_Item( i , "Item" + i ); } listBox1.get_Items().AddRange(ItemObject);
Array<System::Object^>^ ItemObject = gcnew Array<System::Object^>(10); for (int i = 0; i <= 9; i++) { ItemObject[i] = String::Concat("Item", i.ToString()); } listBox1->Items->AddRange(ItemObject);
To remove an item
Call the
Remove
orRemoveAt
method to delete items.Remove
has one argument that specifies the item to remove.RemoveAt
removes the item with the specified index number.' To remove item with index 0: ComboBox1.Items.RemoveAt(0) ' To remove currently selected item: ComboBox1.Items.Remove(ComboBox1.SelectedItem) ' To remove "Tokyo" item: ComboBox1.Items.Remove("Tokyo")
// To remove item with index 0: comboBox1.Items.RemoveAt(0); // To remove currently selected item: comboBox1.Items.Remove(comboBox1.SelectedItem); // To remove "Tokyo" item: comboBox1.Items.Remove("Tokyo");
// To remove item with index 0: comboBox1.get_Items().RemoveAt(0); // To remove currently selected item: comboBox1.get_Items().Remove(comboBox1.get_SelectedItem()); // To remove "Tokyo" item: comboBox1.get_Items().Remove("Tokyo");
// To remove item with index 0: comboBox1->Items->RemoveAt(0); // To remove currently selected item: comboBox1->Items->Remove(comboBox1->SelectedItem); // To remove "Tokyo" item: comboBox1->Items->Remove("Tokyo");
To remove all items
Call the Clear method to remove all items from the collection:
ListBox1.Items.Clear()
listBox1.Items.Clear();
listBox1.get_Items().Clear();
listBox1->Items->Clear();
See Also
Tasks
How to: Sort the Contents of a Windows Forms ComboBox, ListBox, or CheckedListBox Control
Reference
ComboBox
ListBox
CheckedListBox
Concepts
When to Use a Windows Forms ComboBox Instead of a ListBox