論壇中有用戶提出如何通過鼠標移動選擇區域，但不希望選擇區域圖片伴隨移動。考慮到會有其他用戶也會用到這個場景，所以在此共享給大家。

步驟如下：

使用 AddRectangleToRegion 設置選擇區域：

codecs = new RasterCodecs();
rasterImageViewer1.Image = codecs.Load(@"..\..\test.png");
rasterImageViewer1.InteractiveRegionRectangle += rasterImageViewer1_InteractiveRegionRectangle;
rasterImageViewer1.InteractiveRegionType = RasterViewerInteractiveRegionType.Rectangle;
rasterImageViewer1.Image.AddRectangleToRegion(null, new LeadRect(214, 176, 147, 172), RasterRegionCombineMode.Set);

該功能需要結合鼠標按下、移動及釋放事件進行選擇區域的移動：

rasterImageViewer1.MouseDown += rasterImageViewer1_MouseDown;
rasterImageViewer1.MouseMove += rasterImageViewer1_MouseMove;
rasterImageViewer1.MouseUp += rasterImageViewer1_MouseUp;

使用 MouseDown 事件開啟移動標記位：

bool flag = false;
void rasterImageViewer1_MouseDown(object sender, MouseEventArgs e)
{
flag = true;
}

在 MouseMove 事件中通過重繪選擇區域實現移動：

void rasterImageViewer1_MouseMove(object sender, MouseEventArgs e)
{
if (flag)
{
LeadRect lr = rasterImageViewer1.Image.GetRegion(null).GetBounds();
rasterImageViewer1.Image.AddRectangleToRegion(null, new LeadRect(e.X-214, e.Y-176, 147, 172), RasterRegionCombineMode.Set);
}
}
在 MouseUp 事件中關閉移動標記：

void rasterImageViewer1_MouseUp(object sender, MouseEventArgs e)
{
flag = false;
}

效果圖：

文章轉自：葡萄城產品博客