实现方法分为两大类：窗体事件和控件事件，下面就一一展示：

    一、FormClosing事件（又分以下几种方法）

    a.

Private Sub frmPractise_FormClosing(ByVal sender As Object, ByVal e As System.Windows.Forms.FormClosingEventArgs) Handles Me.FormClosing        If MessageBox.Show("确定退出吗？", "退出确认", MessageBoxButtons.YesNo, MessageBoxIcon.Question) = Windows.Forms.DialogResult.No Then            e.Cancel = True        End If    End Sub

    b.

Private Sub Practise_FormClosing(ByVal sender As Object, ByVal e As System.Windows.Forms.FormClosingEventArgs) Handles Me.FormClosing        If MsgBox("确定退出吗？", MessageBoxButtons.OKCancel, "退出确认") = Windows.Forms.DialogResult.Cancel Then            e.Cancel = True        End If    End Sub

    c.

Private Sub Practise_FormClosing(ByVal sender As Object, ByVal e As System.Windows.Forms.FormClosingEventArgs) Handles Me.FormClosing        Dim p As Integer        p = MsgBox("你真的要退出系统吗？", MsgBoxStyle.OkCancel, "提示")        If p = 2 Then            e.Cancel = True        End If    End Sub

    d.(最为简单)

Private Sub Practise_FormClosing(ByVal sender As Object, ByVal e As System.Windows.Forms.FormClosingEventArgs) Handles Me.FormClosing        If MsgBox("你确认要退出程序吗？", MsgBoxStyle.OkCancel, "退出提示") = MsgBoxResult.Cancel Then e.Cancel = True    End Sub

    以上只是点击窗口关闭按钮时的用法，若直接在窗体控件上点击退出时，可以用以下方式实现：

    二、Button_Click事件

Private Sub btnQuit_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles btnQuit.Click        If MsgBox("是否要退出系统？", MsgBoxStyle.YesNo + MsgBoxStyle.Question, "提示") = MsgBoxResult.Yes Then            Application.Exit()        End If    End Sub

VB.Net中确认退出对话框的实现