在绘图板上画矩形，标注尺寸，求助怎么将高度尺寸旋转90度显示，原始代码如下：

    Dim p As WinForm.Painter = e.Form.Controls("画图")

    Dim g As Graphics = p.Graphics

         g.Clear(Color.White)        \'清空

    Dim L1 As New Pen(Color.Blue,0.2)

    g.DrawRectangle(L,10,10,700,700)   \'边框

    Dim dr As Row = Tables("明细表").Current

    Dim a,n,m,w,w1,h,b,ztw,zp,sp As Single

    n = 100                                              \'初始宽度

    m = 100                                              \'初始高度

    w = dr("宽")

    h = dr("高")

    g.DrawRectangle(L1,n,m,w,h)                          \'外框外线

    g.DrawLine(L1,n,m+h+10,n,m+24+h)                    \'总宽标尺左竖线,   10为标尺到框底的距离,

    g.DrawLine(L1,n+w,m+10+h,n+w,m+24+h)                \'总宽标尺右竖线

    g.DrawLine(L1,n,m+17+h,n+(w-50)/2,m+17+h)           \'总宽标尺左横线    50为预留文本尺寸

    g.DrawLine(L1,n+(w-50)/2+50,m+17+h,n+w,m+17+h)      \'总宽标尺右横线

    g.DrawLine(L1,n+w+15,m,n+w+29,m)                    \'总高标尺上横线,   10为标尺到框的距离

    g.DrawLine(L1,n+w+15,m+h,n+w+29,m+h)                \'总高标尺下横线

    g.DrawLine(L1,n+w+22,m,n+w+22,m+(h-50)/2-7)         \'总高标尺上竖线    50为预留文本尺寸

    g.DrawLine(L1,n+w+22,m+h,n+w+22,m+(h-50)/2+64)      \'总高标尺下竖线

Dim fnt As New Font("宋体",12)                                 \'总尺寸字体

Dim msg As String = dr("宽")                                   \'总宽尺寸

g.DrawString(msg,fnt,Brushes.Red,n+w/2,m+h)

Dim msg1 As String = dr("高")           \'总高尺寸

g.DrawString(msg1,fnt,Brushes.Red,n+w,m+h/2)

p.Repaint()