请问 怎么在屏幕指定的位置画个圈 用什么函数？

为啥我花出来的是这样 圈中间的完全看不见了 求大神指点解决方法0.0

最简单的就是将窗体设为无边框窗体 指定透明色 使用API
SetLayeredWindowAttributes 轻松搞定

Option Explicit
Private Declare Function GetDC Lib "user32.dll" (ByVal hWnd As Long) As Long
Private Declare Function ReleaseDC Lib "user32.dll" (ByVal hWnd As Long, ByVal hdc As Long) As Long
Private Declare Function Arc& Lib "gdi32" (ByVal hdc As Long, ByVal X1 As Long, ByVal Y1 As Long, ByVal X2 As Long, ByVal Y2 As Long, ByVal X3 As Long, ByVal Y3 As Long, ByVal X4 As Long, ByVal Y4 As Long)
Private Sub Command1_Click()
Dim lngDC As Long
lngDC = GetDC(0)
Arc lngDC, 100, 100, 500, 500, 0, 0, 0, 0
ReleaseDC 0, lngDC
End Sub

用的 Shape 控件画的圆 然后用的半透明窗体 置顶 然后 鼠标穿透...... 有需要的就把代码拿去吧！

Const LWA_COLORKEY = &H1
Const LWA_ALPHA = &H2
Const GWL_EXSTYLE = (-20)
Const WS_EX_LAYERED = &H80000
Const WS_EX_TRANSPARENT As Long = &H20&
Private Declare Function GetWindowLong Lib "user32" Alias "GetWindowLongA" (ByVal hwnd As Long, ByVal nIndex As Long) As Long
Private Declare Function SetWindowLong Lib "user32" Alias "SetWindowLongA" (ByVal hwnd As Long, ByVal nIndex As Long, ByVal dwNewLong As Long) As Long
Private Declare Function SetLayeredWindowAttributes Lib "user32" (ByVal hwnd As Long, ByVal crKey As Long, ByVal bAlpha As Byte, ByVal dwFlags As Long) As Long
Private Declare Function SetWindowPos Lib "user32" (ByVal hwnd As Long, ByVal hWndInsertAfter As Long, ByVal x As Long, ByVal y As Long, ByVal cx As Long, ByVal cy As Long, ByVal wFlags As Long) As Long
Private Const HWND_TOPMOST& = -1
' 将窗口置于列表顶部，并位于任何最顶部窗口的前面
Private Const SWP_NOSIZE& = &H1
' 保持窗口大小
Private Const SWP_NOMOVE& = &H2
' 保持窗口位置
Private Sub Timer1_Timer()
SetWindowPos Me.hwnd, HWND_TOPMOST, 0, 0, 0, 0, SWP_NOMOVE Or SWP_NOSIZE
' 将窗口设为总在最前
End Sub
Rem 可以把窗体设计我无边框的,自己设计关闭按钮
Private Sub Form_Load()
Dim lRet As Long
FillStyle = 1
Circle (1800, 1000), 800, , , , 1
lRet = GetWindowLong(Me.hwnd, GWL_EXSTYLE)
lRet = Ret Or WS_EX_LAYERED Or WS_EX_TRANSPARENT
SetWindowLong Me.hwnd, GWL_EXSTYLE, lRet
SetLayeredWindowAttributes Me.hwnd, 0, 100, LWA_ALPHA
End Sub