ListBox Constructor ()


Initializes a new instance of the ListBox class.

Namespace:   System.Windows.Forms
Assembly:  System.Windows.Forms (in System.Windows.Forms.dll)

public ListBox()

The following code example demonstrates how to create a ListBox control that displays multiple items in columns and can have more than one item selected in the control's list. The code for the example adds 50 items to the ListBox using the Add method of the ListBox.ObjectCollection class and then selects three items from the list using the SetSelected method. The code then displays values from the ListBox.SelectedObjectCollection collection, through the SelectedItems property, and the ListBox.SelectedIndexCollection, through the SelectedIndices property. This example requires that the code is located in and called from a Form.

private void button1_Click(object sender, System.EventArgs e)
   // Create an instance of the ListBox.
   ListBox listBox1 = new ListBox();
   // Set the size and location of the ListBox.
   listBox1.Size = new System.Drawing.Size(200, 100);
   listBox1.Location = new System.Drawing.Point(10,10);
   // Add the ListBox to the form.
   // Set the ListBox to display items in multiple columns.
   listBox1.MultiColumn = true;
   // Set the selection mode to multiple and extended.
   listBox1.SelectionMode = SelectionMode.MultiExtended;

   // Shutdown the painting of the ListBox as items are added.
   // Loop through and add 50 items to the ListBox.
   for (int x = 1; x <= 50; x++)
      listBox1.Items.Add("Item " + x.ToString());
   // Allow the ListBox to repaint and display the new items.

   // Select three items from the ListBox.
   listBox1.SetSelected(1, true);
   listBox1.SetSelected(3, true);
   listBox1.SetSelected(5, true);

   // Display the second selected item in the ListBox to the console.
   // Display the index of the first selected item in the ListBox.

.NET Framework
Available since 1.1
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