Hi Martin,

I tested your code snippet in a WinForm MC++ project, the following line:
Cursor::Current = Cursors::Default;
seems never been called, it appears the cursor had already been
trapped/beloned by the picture box(m_PicBox) just after you click the left
button of the mouse first time, you cannot trap it in the original function
again.

So I modify the code as following:
...
System::Void Form1_MouseUp(System::Object* sender,
System::Windows::Forms::MouseEventArgs* mea)
{
    if(mea->Button == MouseButtons::Left){
         Cursor::Current->Clip =
Rectangle(m_PicBox->PointToScreen(Point(m_PicBox->ClientRectangle.Left,
m_PicBox->ClientRectangle.Top)), m_PicBox->Size);
}

}

System::Void m_PicBox_MouseUp(System::Object* sender,
System::Windows::Forms::MouseEventArgs* mea)
{
    if(mea->Button == MouseButtons::Left){
        this->Cursor = new
System::Windows::Forms::Cursor(Cursor::Current->Handle);
        Cursor::Clip =  Rectangle(this->Location, this->Size);
   }
}
...

Wish it helps!

Best regards,

Gary Chang
Microsoft Online Partner Support

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