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title, ms.date, description, dev_langs, helpviewer_keywords, ms.assetid
title ms.date description dev_langs helpviewer_keywords ms.assetid
Add and Remove Items from ComboBox, ListBox, or CheckedListBox Control 03/30/2017 Learn how to add and remove a Windows Forms ComboBox, ListBox, and CheckedListBox controls simply and with no data binding.
csharp
vb
cpp
combo boxes [Windows Forms], adding items
list boxes [Windows Forms], removing items
ComboBox control [Windows Forms], adding and removing items
ListBox control [Windows Forms], adding and removing items
list boxes [Windows Forms], adding items
combo boxes [Windows Forms], removing items
CheckedListBox control [Windows Forms], adding and removing items
7224c8d2-4118-443e-ae1e-d7c17d1e69ee

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's ToString method.

To add items

  1. 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->Items->Add("Tokyo");  
    
    • or -
  2. 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->Items->Insert(0, "Copenhagen");  
    
    • or -
  3. 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);  
    
    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

  1. Call the Remove or RemoveAt 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->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

  1. Call the Clear method to remove all items from the collection:

    ListBox1.Items.Clear()  
    
    listBox1.Items.Clear();  
    
    listBox1->Items->Clear();  
    

See also