我正在创建一个工具，可以抓取屏幕上任何内容的颜色，无论是在表单内部还是在表单外部。用户将使用鼠标光标通过单击来抓取屏幕上的任何像素。问题是，根据他们点击的内容，它可能会单击按钮或选择并突出显示图标。为了解决这个问题，我使用了SetWindowsHookEx（）方法来全局禁用鼠标点击事件。这有效。但现在问题是我的应用程序无法检测到click事件已经发生。我已尝试在不同位置和不同时刻取消鼠标，但它会使鼠标禁用或重新启用鼠标，并仍然按照上面提到的不必要的点击进行操作。
在用户可以抓取像素颜色的时间内，计时器正在运行。很显然，我会别无选择，只能在处于＆＃34;像素抓取模式的情况下保持鼠标脱钩状态。为了贯彻抓住像素颜色。我已经尝试过设置mousehook然后在之后解除它，但这也不起作用。这似乎是一个问题22.当然，我有一个ESC和ENTER键的键盘事件作为停止计时器和解开鼠标的替代方案。 ESC键取消＆＃34;取消＆＃34;操作和ENTER键用于抓取像素颜色并停止计时器。但我希望鼠标点击执行相同的功能，而无需点击/激活其他任何东西。这是我的代码。
Private Structure MSLLHOOKSTRUCT
Public pt As Point
Public mouseData As Int32
Public flags As Int32
Public time As Int32
Public extra As IntPtr
End Structure
Private mHook As IntPtr = IntPtr.Zero
Private Const WH_MOUSE_LL As Int32 = &HE
Private Const WM_RBUTTONDOWN As Int32 = &H204
Private Const WM_LBUTTONDOWN As Int32 = &H201
<MarshalAs(UnmanagedType.FunctionPtr)> Private mProc As MouseHookDelegate
Private Declare Function SetWindowsHookExW Lib "user32.dll" (ByVal idHook As Int32, ByVal HookProc As MouseHookDelegate, ByVal hInstance As IntPtr, ByVal wParam As Int32) As IntPtr
Private Declare Function UnhookWindowsHookEx Lib "user32.dll" (ByVal hook As IntPtr) As Boolean
Private Declare Function CallNextHookEx Lib "user32.dll" (ByVal idHook As Int32, ByVal nCode As Int32, ByVal wParam As IntPtr, ByRef lParam As MSLLHOOKSTRUCT) As Int32
Private Declare Function GetModuleHandleW Lib "kernel32.dll" (ByVal fakezero As IntPtr) As IntPtr
Private Delegate Function MouseHookDelegate(ByVal nCode As Int32, ByVal wParam As IntPtr, ByRef lParam As MSLLHOOKSTRUCT) As Int32
Public Function SetHookMouse() As Boolean
If mHook = IntPtr.Zero Then
mProc = New MouseHookDelegate(AddressOf MouseHookProc)
mHook = SetWindowsHookExW(WH_MOUSE_LL, mProc, GetModuleHandleW(IntPtr.Zero), 0)
End If
Return mHook <> IntPtr.Zero
End Function
Public Sub UnHookMouse()
If mHook = IntPtr.Zero Then Return
UnhookWindowsHookEx(mHook)
mHook = IntPtr.Zero
End Sub
Private Function MouseHookProc(ByVal nCode As Int32, ByVal wParam As IntPtr, ByRef lParam As MSLLHOOKSTRUCT) As Int32
'Label1.Text = "Message=" & wParam.ToInt32.ToString & " X=" & lParam.pt.X.ToString & " Y=" & lParam.pt.Y.ToString
If wParam.ToInt32 = WM_LBUTTONDOWN Then
Return 1
End If
Return CallNextHookEx(WH_MOUSE_LL, nCode, wParam, lParam)
End Function
Private Sub Timer2_Tick(sender As Object, e As EventArgs) Handles Timer2.Tick
Using bmp2 As New Bitmap(1, 1)
Using g As Graphics = Graphics.FromImage(bmp2)
g.CopyFromScreen(Cursor.Position,
New Point(0, 0), New Size(1, 1))
End Using
firsty = bmp2.GetPixel(0, 0).ToArgb
ToolStripButton7.BackColor = Color.FromArgb(firsty)
Form4.PictureBox1.BackColor = Color.FromArgb(firsty)
Form4.PictureBox5.BackColor = Color.FromArgb(firsty)
Form4.PictureBox4.BackColor = Color.FromArgb(firsty)
Form4.PictureBox3.BackColor = Color.FromArgb(firsty)
Panel3.BackColor = Color.FromArgb(firsty)
Me.Invalidate()
Dim CodeCodeInHex As String = bmp2.GetPixel(0, 0).ToArgb().ToString("X")
CodeCodeInHex = CodeCodeInHex.Remove(0, 2)
BGCOLOR.Text = "#" & CodeCodeInHex
Form4.Label1.Text = "#" & CodeCodeInHex
Label3.Text = "#" & CodeCodeInHex
End Using
SetHookMouse()
UnHookMouse()
Select Case MouseButtons
Case MouseButtons.Left
Cursor = Cursors.Default
Form4.Close()
SplitContainer3.SplitterDistance = SplitContainer3.Width - SPLITC3
Me.TopMost = True
ColorDialog1.Color = Color.FromArgb(firsty)
ToolStripTextBox1.Text = ColorDialog1.Color.A & ", " & ColorDialog1.Color.R & ", " & ColorDialog1.Color.G & ", " & ColorDialog1.Color.B
Panel2.Visible = False
If CSSToolbarToolStripMenuItem.Checked = True Then
Else
SplitContainer3.Panel2Collapsed = True
End If
Timer2.Stop()
Me.TopMost = False
Case MouseButtons.Right
Case MouseButtons.Middle
Case MouseButtons.Left + MouseButtons.Right
End Select
End Sub
或者，我也考虑采用不同的方法来解决这个问题。在此像素颜色抓取模式下，鼠标光标悬停在辅助表单上的图片框上。表单跟随鼠标光标并保持其形式的死角。它正在悬停的图片框有一个背景颜色的Lime，它是表单的透明度键，从而使其透明，允许用户看到表单后面的屏幕并抓住鼠标光标指向的像素颜色。
因此，知道这一点，或许我可以以某种方式使其表现得好像它点击了图片框而不是它背后的东西。但我还没有找到解决方案。我对你可能拥有的任何方法持开放态度。谢谢。我已经考虑过将图片盒设置为半透明，它是透明但不完全的地方，因为它可以防止任何点击，但这会使得它抓取的像素颜色不准确。我曾经做过一个应用程序，在整个屏幕上最大化无边框形式，并调整其不透明度以制作屏幕亮度滤镜＆＃34;并允许它被点击，但这与我在这里尝试做的相反。所以我想知道。
答案 0 :(得分：1)
我认为你过于复杂了......你已经有了一个鼠标钩子来检测鼠标点击，所以不要只在钩子回调中的WM_LBUTTONDOWN上返回1，而是做你的＆＃34;得到颜色＆＃34 ; -logic在那里。
例如，创建一个在某个位置获取颜色的函数：
Private Function GetScreenPixelColor(ByVal Position As Point) As Color
Using bmp As New Bitmap(1, 1)
Using g As Graphics = Graphics.FromImage(bmp)
g.CopyFromScreen(Position, New Point(0, 0), New Size(1, 1))
End Using
Return bmp.GetPixel(0, 0)
End Using
End Function
然后你需要做的就是调用函数并用结果颜色做一些事情：
If wParam.ToInt32() = WM_LBUTTONDOWN Then
Dim PickedColor As Color = GetScreenPixelColor(Cursor.Position)
'Do something with PickedColor...
UnHookMouse()
Return 1
End If
如果您要在多个场景中应用此逻辑，只需制作另一种方法，为您完成所有事情：
Private Sub PickColor()
Dim PickedColor As Color = GetScreenPixelColor(Cursor.Position)
'Do something with PickedColor...
End Sub
然后你需要做的就是：
If wParam.ToInt32() = WM_LBUTTONDOWN Then
PickColor()
UnHookMouse()
Return 1
End If
答案 1 :(得分：0)
以为我会根据Visual Vincent给出的答案添加我的解决方案。
我创建了一个执行get pixel color方法的函数：
Private Sub getcolor()
Cursor = Cursors.Default
Form4.Close()
SplitContainer3.SplitterDistance = SplitContainer3.Width - SPLITC3
Me.TopMost = True
ColorDialog1.Color = Color.FromArgb(firsty)
ToolStripTextBox1.Text = ColorDialog1.Color.A & ", " & ColorDialog1.Color.R & ", " & ColorDialog1.Color.G & ", " & ColorDialog1.Color.B
Panel2.Visible = False
If CSSToolbarToolStripMenuItem.Checked = True Then
Else
SplitContainer3.Panel2Collapsed = True
End If
Timer2.Stop()
Me.TopMost = False
End Sub
然后在mousehook函数中调用函数：
Private Function MouseHookProc(ByVal nCode As Int32, ByVal wParam As IntPtr, ByRef lParam As MSLLHOOKSTRUCT) As Int32
'Label1.Text = "Message=" & wParam.ToInt32.ToString & " X=" & lParam.pt.X.ToString & " Y=" & lParam.pt.Y.ToString
If wParam.ToInt32 = WM_LBUTTONDOWN Then
getcolor()
Return 1
End If
Return CallNextHookEx(WH_MOUSE_LL, nCode, wParam, lParam)
End Function