wpf 写了一个看图程序 现在大图缩放拖动时 ，缩放图上的缩放框 比例缩放和拖动定位如何实现

[yfp15062328347]

有哪位大神搞过 看图程序 ， 缩放比例和定位 贴上后台代码
double conheight = Container.Height;//获取图片的高度
double sfb = conheight / canvas1.Height;//图片高图/缩放图的高度

//Zoom 缩放比例
sliderScaleTransform.CenterX += tx / zoom / sfb / canvas1.Width;
sliderScaleTransform.CenterY += ty / zoom / sfb / canvas1.Height;
//sliderScaleTransform.CenterX = tx / zoom / sfb;
//sliderScaleTransform.CenterY = ty / zoom / sfb;
if (zoom > oldzoom)
{//现在变大了
//滑块缩放 （小）
double douv = zoom - 1;
double panle2factor = conheight / canvas1.Height;
double v2 = douv / panle2factor;
sliderScaleTransform.ScaleX -= v2;
sliderScaleTransform.ScaleY -= v2;
//sliderScaleTransform.ScaleX -= zoom - oldzoom;
//sliderScaleTransform.ScaleY -= zoom - oldzoom;
//滑块缩放后的尺寸
}
else if (oldzoom > zoom)
{//缩小了
double douv = oldzoom - 1;
double panle2factor = conheight / canvas1.Height;
double v2 = douv / panle2factor;
sliderScaleTransform.ScaleX += v2;
sliderScaleTransform.ScaleY += v2;
//滑块缩放(大)
//sliderScaleTransform.ScaleX += oldzoom - zoom;
//sliderScaleTransform.ScaleY += oldzoom - zoom;
}
else
{
sliderScaleTransform.ScaleX = 1;
sliderScaleTransform.ScaleY = 1;
}

[yfp15062328347]

有谁做过啦，江湖救急呢

[yfp15062328347]

没人看吗，谁诊断下呢

[yfp15062328347]

都没人啊，哪位大神给瞅瞅呢