C# - How to add items to ListBox

listBox1.Items.Clear();

listBox1.Items.Add( "One" );
listBox1.Items.Add( "Two" );
listBox1.Items.Add( "Three" );

, or (from array):

listBox1.Items.Clear();
   
String[] sArray = { "One", "Two", "Three" };
listBox1.Items.AddRange( sArray );

, or

listBox1.DataSource = new string[] { "One", "Two", "Three" };

Output: