Question

vb中。我想用picture1代替标题栏移动窗口，但窗口却消失了。我想是它移到了屏幕外，但为什么？下面是代码

Single)
If Button = 1 Then
xCursor = X
yCursor = Y
End If
End Sub

Private Sub picture1_MouseMove(Button As Integer, Shift As Integer, X As Single, Y As Single)
If Button = 1 Then
Print X
Call SetWindowPos(Me.hwnd, 1, 10 + Me.Left, 10 + Me.Top, 100, 100, SWP_NOSIZE)
End If
End Sub

Answer 1

不需要用API：
Option Explicit

Dim xCursor As Long, yCursor As Long

Private Sub Picture1_MouseDown(Button As Integer, Shift As Integer, X As Single, Y As Single)
If Button And vbLeftButton Then
xCursor = X: yCursor = Y
End If
End Sub

Private Sub Picture1_MouseMove(Button As Integer, Shift As Integer, X As Single, Y As Single)
If Button And vbLeftButton Then
Me.Move Me.Left - xCursor + X, Me.Top - yCursor + Y
End If
End Sub '

追问

我之前也是这样。原来问题在坐标系统上

Answer 2

Private Declare Function SendMessage Lib "user32" Alias "SendMessageA" (ByVal hwnd As Long, ByVal wMsg As Long, ByVal wParam As Long, lParam As Long) As Long
Private Declare Function ReleaseCapture Lib "user32" () As Long
Const WM_NCLBUTTONDOWN = &HA1
Const HTCAPTION = 2

Private Sub Picture1_MouseDown(Button As Integer, Shift As Integer, X As Single, Y As Single)
If Button = 1 Then
Dim ReturnVal As Long
X = ReleaseCapture()
ReturnVal = SendMessage(Me.hwnd, WM_NCLBUTTONDOWN, HTCAPTION, 0)
End If
End Sub