Question

首先，我想知道鼠标是否在某个区域。然后，我想检查鼠标是否按住左键。我想检查只要左按钮关闭，我想跟踪鼠标的位置。最后，检查左按钮何时释放。

那么，简而言之，我应该从哪里开始跟踪表单中的鼠标事件？

Answer 1

这是一个用于检测拖动或单击

的简单代码

Public IsDragging As Boolean = False, IsClick As Boolean = False
Public StartPoint, FirstPoint, LastPoint As Point
Private Sub PictureBox1_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles picBook.Click
    If IsClick = True Then MsgBox("CLick")
End Sub

Private Sub PictureBox1_MouseDown(ByVal sender As Object, ByVal e As System.Windows.Forms.MouseEventArgs) Handles picBook.MouseDown
    StartPoint = picBook.PointToScreen(New Point(e.X, e.Y))
    FirstPoint = StartPoint
    IsDragging = True
End Sub

Private Sub PictureBox1_MouseMove(ByVal sender As Object, ByVal e As System.Windows.Forms.MouseEventArgs) Handles picBook.MouseMove
    If IsDragging Then
        Dim EndPoint As Point = picBook.PointToScreen(New Point(e.X, e.Y))
        IsClick = False
        picBook.Left += (EndPoint.X - StartPoint.X)
        picBook.Top += (EndPoint.Y - StartPoint.Y)
        StartPoint = EndPoint
        LastPoint = EndPoint
    End If
End Sub

Private Sub PictureBox1_MouseUp(ByVal sender As Object, ByVal e As System.Windows.Forms.MouseEventArgs) Handles picBook.MouseUp
    IsDragging = False
    If LastPoint = StartPoint Then IsClick = True Else IsClick = False
End Sub

Answer 2

一般来说，当发生鼠标按下事件时，您需要捕获鼠标。然后，即使鼠标离开捕获鼠标的控件区域，您也会收到鼠标移动事件。您可以在鼠标移动事件中计算delta。第一次增量超过系统定义的“拖动区域”时会发生拖动。收到鼠标按下事件后，停止拖动操作。

在Windows窗体中，查看Control类上的MouseDown，MouseMove和MouseUp事件。 MouseEventArgs将包含X / Y坐标。要捕获或释放鼠标，请分别将Capture属性设置为true或false。如果您没有捕获鼠标，那么如果鼠标被释放到控件的边界之外，则不会收到MouseMove或MouseUp事件。

最后，要确定在开始拖动操作之前应允许鼠标移动的最小“距离”，请查看SystemInformation.DragSize属性。

希望这有帮助。

Answer 3

这样做的唯一方法是通过javascript。

本文将向您解释。 http://luke.breuer.com/tutorial/javascript-drag-and-drop-tutorial.aspx

Answer 4

可以理解这已经过时了，但我在寻找同样的事情时遇到过这篇文章。我以为可能会有一个实际的拖拽事件，但我猜不是。这是我如何做到的。

Private Sub ContainerToolStripMenuItem_Click(sender As System.Object, e As System.EventArgs) Handles ContainerToolStripMenuItem.Click
    Dim pnl As New Panel
    pnl.Size = New Size(160, 160)
    pnl.BackColor = Color.White
    AddHandler pnl.MouseDown, AddressOf Control_DragEnter
    AddHandler pnl.MouseUp, AddressOf Control_DragLeave
    AddHandler pnl.MouseMove, AddressOf Control_Move
    Me.Controls.Add(pnl)
End Sub

Private Sub Control_DragEnter(ByVal sender As Object, ByVal e As EventArgs)
    MouseDragging = True
End Sub

Private Sub Control_DragLeave(ByVal sender As Object, ByVal e As EventArgs)
    MouseDragging = False
End Sub

Private Sub Control_Move(ByVal sender As Object, ByVal e As EventArgs)
    If MouseDragging = True Then
        sender.Location = Me.PointToClient(Control.MousePosition)
    End If
End Sub

ContainerToolStripMenuItem来自我的ToolStrip，它即时添加了一个Panel。 MouseDragging是班级。拖拉机就像一个魅力。此外，请勿使用Cursor.Position，因为它会返回相对于整个窗口的位置，而不是表单（或者您正在使用的任何容器）。

如何在VB.NET中跟踪鼠标单击和拖动事件？

4 个答案: