'実験コード。Form に ListBox だけを貼っておきます。 Public Class Form1 Public Sub New() InitializeComponent() '下記の行をコメントアウトすると、連続した 2 回目の 'Click イベントが、DoubleClick イベントに変更される MyBase.SetStyle(ControlStyles.StandardDoubleClick, False) End Sub '検証用 Private Sub Dump(eventName As String) ListBox1.Items.Insert(0, Now.ToString("[HH:mm:ss.ff]") & eventName) ListBox1.SelectedIndex = 0 End Sub Private Sub Form1_MouseDown(sender As Object, e As MouseEventArgs) Handles Me.MouseDown Dump("MouseDown/" & e.Button.ToString()) End Sub Private Sub Form1_MouseClick(sender As Object, e As MouseEventArgs) Handles Me.MouseClick Dump("MouseClick/" & e.Button.ToString()) End Sub Private Sub Form1_MouseUp(sender As Object, e As MouseEventArgs) Handles Me.MouseUp Dump("MouseUp/" & e.Button.ToString()) End Sub Private Sub Form1_Click(sender As Object, e As EventArgs) Handles Me.Click Dump("Click/" & MouseButtons.ToString()) End Sub Private Sub Form1_DoubleClick(sender As Object, e As EventArgs) Handles Me.DoubleClick Dump("DoubleClick/" & MouseButtons.ToString()) End Sub End Class