C# C笔错误#

我用鼠标做了一个选择区域的系统。 但是，当我选择该区域时，该区域如下所示：

对不起，我的英语，我是巴西人

我的代码：

    private void ResizeSelection()
    {

        if (CurrentAction == ClickAction.LeftSizing)
        {

            if (Cursor.Position.X < CurrentBottomRight.X - 10)
            {

                //Erase the previous rectangle
                g.DrawRectangle(EraserPen, CurrentTopLeft.X, CurrentTopLeft.Y, RectangleWidth, RectangleHeight);
                CurrentTopLeft.X = Cursor.Position.X;
                RectangleWidth = CurrentBottomRight.X - CurrentTopLeft.X;
                g.DrawRectangle(MyPen, CurrentTopLeft.X, CurrentTopLeft.Y, RectangleWidth, RectangleHeight);

            }

        }
        if (CurrentAction == ClickAction.TopLeftSizing)
        {

            if (Cursor.Position.X < CurrentBottomRight.X - 10 && Cursor.Position.Y < CurrentBottomRight.Y - 10)
            {

                //Erase the previous rectangle
                g.DrawRectangle(EraserPen, CurrentTopLeft.X, CurrentTopLeft.Y, RectangleWidth, RectangleHeight);
                CurrentTopLeft.X = Cursor.Position.X;
                CurrentTopLeft.Y = Cursor.Position.Y;
                RectangleWidth = CurrentBottomRight.X - CurrentTopLeft.X;
                RectangleHeight = CurrentBottomRight.Y - CurrentTopLeft.Y;
                g.DrawRectangle(MyPen, CurrentTopLeft.X, CurrentTopLeft.Y, RectangleWidth, RectangleHeight);

            }
        }
        if (CurrentAction == ClickAction.BottomLeftSizing)
        {

            if (Cursor.Position.X < CurrentBottomRight.X - 10 && Cursor.Position.Y > CurrentTopLeft.Y + 10)
            {

                //Erase the previous rectangle
                g.DrawRectangle(EraserPen, CurrentTopLeft.X, CurrentTopLeft.Y, RectangleWidth, RectangleHeight);
                CurrentTopLeft.X = Cursor.Position.X;
                CurrentBottomRight.Y = Cursor.Position.Y;
                RectangleWidth = CurrentBottomRight.X - CurrentTopLeft.X;
                RectangleHeight = CurrentBottomRight.Y - CurrentTopLeft.Y;
                g.DrawRectangle(MyPen, CurrentTopLeft.X, CurrentTopLeft.Y, RectangleWidth, RectangleHeight);

            }

        }
        if (CurrentAction == ClickAction.RightSizing)
        {

            if (Cursor.Position.X > CurrentTopLeft.X + 10)
            {

                //Erase the previous rectangle
                g.DrawRectangle(EraserPen, CurrentTopLeft.X, CurrentTopLeft.Y, RectangleWidth, RectangleHeight);
                CurrentBottomRight.X = Cursor.Position.X;
                RectangleWidth = CurrentBottomRight.X - CurrentTopLeft.X;
                g.DrawRectangle(MyPen, CurrentTopLeft.X, CurrentTopLeft.Y, RectangleWidth, RectangleHeight);

            }
        }
        if (CurrentAction == ClickAction.TopRightSizing)
        {

            if (Cursor.Position.X > CurrentTopLeft.X + 10 && Cursor.Position.Y < CurrentBottomRight.Y - 10)
            {

                //Erase the previous rectangle
                g.DrawRectangle(EraserPen, CurrentTopLeft.X, CurrentTopLeft.Y, RectangleWidth, RectangleHeight);
                CurrentBottomRight.X = Cursor.Position.X;
                CurrentTopLeft.Y = Cursor.Position.Y;
                RectangleWidth = CurrentBottomRight.X - CurrentTopLeft.X;
                RectangleHeight = CurrentBottomRight.Y - CurrentTopLeft.Y;
                g.DrawRectangle(MyPen, CurrentTopLeft.X, CurrentTopLeft.Y, RectangleWidth, RectangleHeight);

            }
        }
        if (CurrentAction == ClickAction.BottomRightSizing)
        {

            if (Cursor.Position.X > CurrentTopLeft.X + 10 && Cursor.Position.Y > CurrentTopLeft.Y + 10)
            {

                //Erase the previous rectangle
                g.DrawRectangle(EraserPen, CurrentTopLeft.X, CurrentTopLeft.Y, RectangleWidth, RectangleHeight);
                CurrentBottomRight.X = Cursor.Position.X;
                CurrentBottomRight.Y = Cursor.Position.Y;
                RectangleWidth = CurrentBottomRight.X - CurrentTopLeft.X;
                RectangleHeight = CurrentBottomRight.Y - CurrentTopLeft.Y;
                g.DrawRectangle(MyPen, CurrentTopLeft.X, CurrentTopLeft.Y, RectangleWidth, RectangleHeight);

            }
        }
        if (CurrentAction == ClickAction.TopSizing)
        {

            if (Cursor.Position.Y < CurrentBottomRight.Y - 10)
            {

                //Erase the previous rectangle
                g.DrawRectangle(EraserPen, CurrentTopLeft.X, CurrentTopLeft.Y, RectangleWidth, RectangleHeight);
                CurrentTopLeft.Y = Cursor.Position.Y;
                RectangleHeight = CurrentBottomRight.Y - CurrentTopLeft.Y;
                g.DrawRectangle(MyPen, CurrentTopLeft.X, CurrentTopLeft.Y, RectangleWidth, RectangleHeight);

            }
        }
        if (CurrentAction == ClickAction.BottomSizing)
        {

            if (Cursor.Position.Y > CurrentTopLeft.Y + 10)
            {

                //Erase the previous rectangle
                g.DrawRectangle(EraserPen, CurrentTopLeft.X, CurrentTopLeft.Y, RectangleWidth, RectangleHeight);
                CurrentBottomRight.Y = Cursor.Position.Y;
                RectangleHeight = CurrentBottomRight.Y - CurrentTopLeft.Y;
                g.DrawRectangle(MyPen, CurrentTopLeft.X, CurrentTopLeft.Y, RectangleWidth, RectangleHeight);

            }

        }

    }

private void ResizeSelection（）
{
如果（CurrentAction==ClickAction.LeftSize）
{
if（光标位置XCurrentTopLeft.Y+10）
{
//删除上一个矩形
g、 DrawRectangle（橡皮擦、CurrentTopLeft.X、CurrentTopLeft.Y、矩形宽度、矩形高度）；
CurrentTopLeft.X=Cursor.Position.X；
CurrentBottomRight.Y=Cursor.Position.Y；
矩形宽度=CurrentBottomRight.X-CurrentTopLeft.X；
矩形高度=CurrentBottomRight.Y-CurrentTopLeft.Y；
g、 DrawRectangle（MyPen、CurrentTopLeft.X、CurrentTopLeft.Y、矩形宽度、矩形高度）；
}
}
如果（CurrentAction==ClickAction.RightSize）
{
if（Cursor.Position.X>CurrentTopLeft.X+10）
{
//删除上一个矩形
g、 DrawRectangle（橡皮擦、CurrentTopLeft.X、CurrentTopLeft.Y、矩形宽度、矩形高度）；
CurrentBottomRight.X=Cursor.Position.X；
矩形宽度=CurrentBottomRight.X-CurrentTopLeft.X；
g、 DrawRectangle（MyPen、CurrentTopLeft.X、CurrentTopLeft.Y、矩形宽度、矩形高度）；
}
}
如果（CurrentAction==ClickAction.TopRightSize）
{
if（Cursor.Position.X>CurrentTopLeft.X+10&&Cursor.Position.YCurrentTopLeft.X+10&&Cursor.Position.Y>CurrentTopLeft.Y+10）
{
//删除上一个矩形
g、 DrawRectangle（橡皮擦、CurrentTopLeft.X、CurrentTopLeft.Y、矩形宽度、矩形高度）；
CurrentBottomRight.X=Cursor.Position.X；
CurrentBottomRight.Y=Cursor.Position.Y；
矩形宽度=CurrentBottomRight.X-CurrentTopLeft.X；
矩形高度=CurrentBottomRight.Y-CurrentTopLeft.Y；
g、 DrawRectangle（MyPen、CurrentTopLeft.X、CurrentTopLeft.Y、矩形宽度、矩形高度）；
}
}
如果（CurrentAction==ClickAction.TopSizing）
{
if（光标位置YCurrentTopLeft.Y+10）
{
//删除上一个矩形
g、 DrawRectangle（橡皮擦、CurrentTopLeft.X、CurrentTopLeft.Y、矩形宽度、矩形高度）；
CurrentBottomRight.Y=Cursor.Position.Y；
矩形高度=CurrentBottomRight.Y-CurrentTopLeft.Y；
g、 DrawRectangle（MyPen、CurrentTopLeft.X、CurrentTopLeft.Y、矩形宽度、矩形高度）；
}
}
}

我想知道是否有办法解决这个问题，或者让它变得透明，只显示矩形的边缘。

---

谢谢，

您误用了

图形

决不能调用
CreateGraphics（）
在控件上绘制；它将在下一道漆上擦除

相反，您应该处理
Paint
事件，并在每次重新绘制时绘制所需的所有内容

当鼠标移动时，调用
Invalidate（）