{"id":935,"date":"2021-09-23T21:47:48","date_gmt":"2021-09-23T13:47:48","guid":{"rendered":"http:\/\/www.wayln.com\/?p=935"},"modified":"2021-09-23T22:39:11","modified_gmt":"2021-09-23T14:39:11","slug":"%e6%95%88%e6%9e%9c%e5%92%8c%e5%8f%af%e8%a7%86%e5%8c%96%e5%af%b9%e8%b1%a1","status":"publish","type":"post","link":"https:\/\/www.wayln.com\/?p=935","title":{"rendered":"\u6548\u679c\u548c\u53ef\u89c6\u5316\u5bf9\u8c61"},"content":{"rendered":"<div id=\"toc_container\" class=\"toc_transparent no_bullets\"><p class=\"toc_title\">Contents<\/p><ul class=\"toc_list\"><li><a href=\"#i\"><span class=\"toc_number toc_depth_1\">1<\/span> \u53ef\u89c6\u5316\u5bf9\u8c61<\/a><ul><li><a href=\"#i-2\"><span class=\"toc_number toc_depth_2\">1.1<\/span> \u7ed8\u5236\u53ef\u89c6\u5316\u5bf9\u8c61<\/a><\/li><li><a href=\"#DrawingContextDrawingVisualTransformOpacityRenderOpen\"><span class=\"toc_number toc_depth_2\">1.2<\/span> \u4e00\u65e6\u5173\u95edDrawingContext\u5bf9\u8c61\uff0c\u5c31\u4e0d\u80fd\u518d\u4fee\u6539\u53ef\u89c6\u5316\u5bf9\u8c61\u3002\u4f46\u53ef\u4ee5\u4f7f\u7528DrawingVisual\u7c7b\u7684Transform\u548cOpacity\u5c5e\u6027\u5e94\u7528\u53d8\u6362\u6216\u6539\u53d8\u6574\u4e2a\u53ef\u89c6\u5316\u5bf9\u8c61\u7684\u900f\u660e\u5ea6\u3002\u5982\u679c\u5e0c\u671b\u63d0\u4f9b\u5168\u65b0\u7684\u5185\u5bb9\uff0c\u53ef\u4ee5\u518d\u6b21\u8c03\u7528RenderOpen()\u65b9\u6cd5\u5e76\u91cd\u590d\u7ed8\u5236\u8fc7\u7a0b\u3002<\/a><\/li><li><a href=\"#PenBrushPenBrush\"><span class=\"toc_number toc_depth_2\">1.3<\/span> \u8bb8\u591a\u7ed8\u56fe\u65b9\u6cd5\u90fd\u4f7f\u7528Pen\u548cBrush\u5bf9\u8c61\uff0c\u5982\u679c\u8ba1\u5212\u4f7f\u7528\u76f8\u540c\u7684\u7b14\u753b\u548c\u586b\u5145\u7ed8\u5236\u8bb8\u591a\u53ef\u89c6\u5316\u5bf9\u8c61\uff0c\u5c31\u503c\u5f97\u4e8b\u5148\u521b\u5efa\u6240\u9700\u7684Pen\u548cBrush\u5bf9\u8c61\uff0c\u5e76\u5728\u7a97\u53e3\u7684\u6574\u4e2a\u751f\u547d\u5468\u671f\u4e2d\u4fdd\u5b58\u4ed6\u4eec\u3002<\/a><\/li><li><a href=\"#i-3\"><span class=\"toc_number toc_depth_2\">1.4<\/span> \u5728\u5143\u7d20\u4e2d\u5c01\u88c5\u53ef\u89c6\u5316\u5bf9\u8c61<\/a><\/li><li><a href=\"#i-4\"><span class=\"toc_number toc_depth_2\">1.5<\/span> \u547d\u4e2d\u6d4b\u8bd5<\/a><\/li><\/ul><\/li><\/ul><\/div>\n<h1><span id=\"i\">\u53ef\u89c6\u5316\u5bf9\u8c61<\/span><\/h1>\n<p>\u901a\u8fc7\u51e0\u4f55\u56fe\u5f62\u3001\u56fe\u753b\u548c\u8def\u5f84\u53ef\u4ee5\u964d\u4f4e2D\u56fe\u5f62\u7684\u5f00\u9500\u3002\u4f46\u662f\u4e0d\u9002\u5408\u9700\u8981\u6e32\u67d3\u5927\u91cf\u56fe\u5f62\u5143\u7d20\u7684\u7ed8\u56fe\u5bc6\u96c6\u578b\u5e94\u7528\u7a0b\u5e8f\uff0c\u4f8b\u5982\u7ed8\u56fe\u7a0b\u5e8f\uff0c\u6f14\u793a\u4f8b\u5b50\u78b0\u649e\u7684\u7269\u7406\u6a21\u578b\u6216\u6a2a\u5411\u5377\u8f74\u5f62\u5f0f\u7684\u6e38\u620f\u3002\u5373\u4f7f\u4f7f\u7528\u91cf\u7ea7\u66f4\u8f7b\u7684Geometry\u5bf9\u8c61\u4ee3\u66ffPath\u5143\u7d20\uff0c\u9700\u8981\u7684\u5f00\u9500\u4e5f\u4ecd\u4f1a\u8f83\u5927\u5f71\u54cd\u5e94\u7528\u7a0b\u5e8f\u6027\u80fd\u3002<br \/>\n\u89e3\u51b3\u6b64\u7c7b\u95ee\u9898\u7684\u65b9\u6848\u662f\uff0c\u4f7f\u7528\u4f4e\u7ea7\u7684\u53ef\u89c6\u5316\u5c42\uff08visual layer\uff09\u6a21\u578b\u3002<\/p>\n<h2><span id=\"i-2\">\u7ed8\u5236\u53ef\u89c6\u5316\u5bf9\u8c61<\/span><\/h2>\n<p>Visual\u7c7b\u662f\u62bd\u8c61\u7c7b\uff0c\u6240\u4ee5\u4e0d\u80fd\u521b\u5efa\u8be5\u7c7b\u7684\u5b9e\u4f8b\u3002\u6700\u6709\u7528\u7684\u6d3e\u751f\u7c7b\u662fDrawingVisual\u7c7b\u3002\u8be5\u7c7b\u7ee7\u627f\u81eaContainerVisual\u7c7b\uff0c\u5e76\u589e\u52a0\u4e86\u652f\u6301\u201c\u7ed8\u5236\u201d\u5e0c\u671b\u9632\u6b62\u5230\u53ef\u89c6\u5316\u5bf9\u8c61\u4e2d\u7684\u56fe\u5f62\u5185\u5bb9\u7684\u529f\u80fd\u3002<br \/>\n\u4e3a\u4e86\u4f7f\u7528DrawingVisual\u7c7b\u7ed8\u5236\u5185\u5bb9\uff0c\u9700\u8981\u8c03\u7528DrawingVisual.RendorOpen()\u65b9\u6cd5\u3002\u8be5\u65b9\u6cd5\u8fd4\u56de\u4e00\u4e2a\u53ef\u7528\u4e8e\u5b9a\u4e49\u53ef\u89c6\u5316\u5185\u5bb9\u7684DrawingContext\u5bf9\u8c61\u3002\u7ed8\u5236\u5b8c\u6bd5\u540e\uff0c\u9700\u8981\u8c03\u7528DrawingContext.Close()\u65b9\u6cd5<\/p>\n<pre><code class=\"language-CSharp line-numbers\">DrawingVisual visual=new DrawingVisual();\nDrawingContext dc=visual.RenderOpen();\n\/\/(Perform drawing here.)\ndc.close();\n<\/code><\/pre>\n<p>\u672c\u8d28\u4e0a\uff0cDrawingContext\u7c7b\u7531\u5404\u79cd\u4e3a\u53ef\u89c6\u5316\u5bf9\u8c61\u589e\u52a0\u4e86\u4e00\u4e9b\u56fe\u5f62\u7ec6\u8282\u7684\u65b9\u6cd5\u6784\u6210\u3002\u53ef\u8c03\u7528\u8fd9\u4e9b\u65b9\u6cd5\u7ed8\u5236\u5404\u79cd\u56fe\u5f62\u3001\u5e94\u7528\u53d8\u6362\u4ee5\u53ca\u6539\u53d8\u4e0d\u900f\u660e\u5ea6\u7b49\u3002<\/p>\n<table>\n<thead>\n<tr>\n<th>\u540d\u79f0<\/th>\n<th>\u8bf4\u660e<\/th>\n<\/tr>\n<\/thead>\n<tbody>\n<tr>\n<td>DrawLine() <br \/> DrawRectangle()<br \/>DrawRoundedRectangle()<br \/>DrawEllips()<\/td>\n<td>\u5728\u6307\u5b9a\u7684\u4f4d\u7f6e\uff0c\u4f7f\u7528\u6307\u5b9a\u7684\u586b\u5145\u548c\u8f6e\u5ed3\u7ed8\u5236\u7279\u5b9a\u7684\u5f62\u72b6<\/td>\n<\/tr>\n<tr>\n<td>DrawGeometry()<br \/>DrawDrawing()<\/td>\n<td>\u7ed8\u5236\u66f4\u590d\u6742\u7684Geometry\u5bf9\u8c61\u548cDrawing\u5bf9\u8c61<\/td>\n<\/tr>\n<tr>\n<td>DrawText()<\/td>\n<td>\u5728\u6307\u5b9a\u7684\u4f4d\u7f6e\u7ed8\u5236\u6587\u672c\uff0c\u901a\u8fc7\u4e3a\u65b9\u6cd5\u4f20\u9012FormattedText\u5bf9\u8c61\uff0c\u53ef\u6307\u5b9a\u6587\u672c\u3001\u5b57\u4f53\u3001\u586b\u5145\u4ee5\u53ca\u5176\u4ed6\u7ec6\u8282\u3002\u5982\u679c\u8bbe\u7f6e\u4e86FormattedText.MaxTextWidth\u5c5e\u6027\uff0c\u53ef\u4f7f\u7528\u8be5\u65b9\u6cd5\u7ed8\u5236\u6362\u884c\u7684\u6587\u672c<\/td>\n<\/tr>\n<tr>\n<td>DrawImage()<\/td>\n<td>\u5728\u6307\u5b9a\u533a\u57df\uff08\u7531Rect\u5bf9\u8c61\u5b9a\u4e49\uff09\u7ed8\u5236\u8863\u670d\u4f4d\u56fe\u56fe\u50cf<\/td>\n<\/tr>\n<tr>\n<td>DrawVideo()<\/td>\n<td>\u5728\u7279\u5b9a\u533a\u57df\u7ed8\u5236\u89c6\u9891\u5185\u5bb9\uff08\u5c01\u88c5\u5728MediaPlayer\u5bf9\u8c61\u4e2d\uff09<\/td>\n<\/tr>\n<tr>\n<td>Pop()<\/td>\n<td>\u53cd\u8f6c\u6700\u540e\u8c03\u7528\u7684PushXxx()\u65b9\u6cd5\uff0c\u53ef\u4f7f\u7528PushXxx()\u65b9\u6cd5\u6682\u65f6\u5e94\u7528\u4e00\u4e2a\u6216\u591a\u4e2a\u6548\u679c\uff0c\u5e76\u4e14Pop()\u65b9\u6cd5\u4f1a\u53cd\u8f6c\u4ed6\u4eec<\/td>\n<\/tr>\n<tr>\n<td>PushClip()<\/td>\n<td>\u4e3a\u7ed8\u56fe\u9650\u5236\u5728\u7279\u5b9a\u526a\u88c1\u533a\u57df\u4e2d\u3002\u8fd9\u4e2a\u533a\u57df\u5916\u7684\u5185\u5bb9\u4e0d\u88ab\u7ed8\u5236<\/td>\n<\/tr>\n<tr>\n<td>PushEffect()<\/td>\n<td>\u4e3a\u968f\u540e\u7684\u7ed8\u56fe\u64cd\u4f5c\u5e94\u7528BitmapEffect\u5bf9\u8c61<\/td>\n<\/tr>\n<tr>\n<td>PushOpacity()<br \/>PushOpacityMask()<\/td>\n<td>\u4e3a\u4e86\u4f7f\u540e\u7eed\u7684\u7ed8\u56fe\u64cd\u4f5c\u90e8\u5206\u900f\u660e\uff0c\u5e94\u7528\u65b0\u7684\u4e0d\u900f\u660e\u8bbe\u7f6e\u6216\u4e0d\u900f\u660e\u63a9\u7801<\/td>\n<\/tr>\n<tr>\n<td>PushTransform()<\/td>\n<td>\u8bbe\u7f6e\u5c06\u5e94\u7528\u4e8e\u540e\u7eed\u7ed8\u5236\u64cd\u4f5c\u7684Transform\u5bf9\u8c61\u3002\u53ef\u4f7f\u7528\u53d8\u6362\u6765\u7f29\u653e\u3001\u79fb\u52a8\u3001\u65cb\u8f6c\u6216\u626d\u66f2\u5185\u5bb9<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n<pre><code class=\"language-CSharp line-numbers\">DrawingVisual visual=new DrawingVisual();\nusing(DrawingContext dc=visual.RenderOpen())\n{\n    Pen drawingPen=new Pen(Brushes.Black,3);\n    dc.DrawingLine(drawingPen,new Point(0,50),new Point(50,0))\uff1b\n        dc.DrawingLine(drawingPen,new Point(50,0),new Point(100,50))\uff1b\n        dc.DrawingLine(drawingPen,new Point(0,50),new Point(100,50))\uff1b\n}\n<\/code><\/pre>\n<p>\u5f53\u8c03\u7528DrawingContext\u65b9\u6cd5\u65f6\uff0c\u6ca1\u6709\u5b9e\u9645\u7ed8\u5236\u53ef\u89c6\u5316\u5bf9\u8c61\u2014\u2014\u800c\u53ea\u662f\u5b9a\u4e49\u4e86\u53ef\u89c6\u5316\u5916\u89c2\u3002\u5f53\u901a\u8fc7\u8c03\u7528Close()\u65b9\u6cd5\u7ed3\u675f\u7ed8\u5236\u65f6\uff0c\u5b8c\u6210\u7684\u56fe\u753b\u88ab\u5b58\u50a8\u5728\u548c\u77f3\u5316\u5bf9\u8c61\u4e2d\uff0c\u5e76\u901a\u8fc7\u53ea\u8bfb\u7684DrawsingVisual.Drawing\u5c5e\u6027\u63d0\u4f9b\u8fd9\u4e9b\u56fe\u753b\u3002WPF\u4f1a\u4fdd\u5b58Drawing\u5bf9\u8c61\uff0c\u4ece\u800c\u5f53\u9700\u8981\u65f6\u53ef\u4ee5\u91cd\u65b0\u7ed8\u5236\u7a97\u53e3\u3002<br \/>\n\u7ed8\u5236\u4ee3\u7801\u7684\u987a\u5e8f\u5f88\u91cd\u8981\u3002\u540e\u9762\u7684\u7ed8\u56fe\u64cd\u4f5c\u53ef\u5728\u5df2\u7ecf\u5b58\u5728\u7684\u56fe\u5f62\u4e0a\u7ed8\u5236\u5185\u5bb9\uff0cPushXxx()\u65b9\u6cd5\u5e94\u7528\u7684\u8bbe\u7f6e\u4f1a\u88ab\u5e94\u7528\u5230\u540e\u7eed\u7684\u7ed8\u56fe\u64cd\u4f5c\u4e2d\u3002\u4f8b\u5982\uff0c\u53ef\u4f7f\u7528PushOpacity()\u65b9\u6cd5\u6539\u53d8\u4e0d\u900f\u660e\u7ea7\u522b\uff0c\u8be5\u8bbe\u7f6e\u4f1a\u5f71\u54cd\u6240\u6709\u7684\u540e\u7eed\u7ed8\u56fe\u64cd\u4f5c\u3002\u53ef\u4f7f\u7528Pop()\u65b9\u6cd5\u6062\u590d\u6700\u8fd1\u7684PushXxx\uff08\uff09\u65b9\u6cd5\u3002\u5982\u679c\u591a\u6b21\u8c03\u7528PushXxx\uff08\uff09\u65b9\u6cd5\uff0c\u53ef\u4e00\u6b21\u4f7f\u7528\u4e00\u7cfb\u5217Pop\u65b9\u6cd5\u8c03\u7528\u5173\u95ed\u4ed6\u4eec\u3002<\/p>\n<h2><span id=\"DrawingContextDrawingVisualTransformOpacityRenderOpen\">\u4e00\u65e6\u5173\u95edDrawingContext\u5bf9\u8c61\uff0c\u5c31\u4e0d\u80fd\u518d\u4fee\u6539\u53ef\u89c6\u5316\u5bf9\u8c61\u3002\u4f46\u53ef\u4ee5\u4f7f\u7528DrawingVisual\u7c7b\u7684Transform\u548cOpacity\u5c5e\u6027\u5e94\u7528\u53d8\u6362\u6216\u6539\u53d8\u6574\u4e2a\u53ef\u89c6\u5316\u5bf9\u8c61\u7684\u900f\u660e\u5ea6\u3002\u5982\u679c\u5e0c\u671b\u63d0\u4f9b\u5168\u65b0\u7684\u5185\u5bb9\uff0c\u53ef\u4ee5\u518d\u6b21\u8c03\u7528RenderOpen()\u65b9\u6cd5\u5e76\u91cd\u590d\u7ed8\u5236\u8fc7\u7a0b\u3002<\/span><\/h2>\n<p>\u63d0\u793a\uff1a<\/p>\n<h2><span id=\"PenBrushPenBrush\">\u8bb8\u591a\u7ed8\u56fe\u65b9\u6cd5\u90fd\u4f7f\u7528Pen\u548cBrush\u5bf9\u8c61\uff0c\u5982\u679c\u8ba1\u5212\u4f7f\u7528\u76f8\u540c\u7684\u7b14\u753b\u548c\u586b\u5145\u7ed8\u5236\u8bb8\u591a\u53ef\u89c6\u5316\u5bf9\u8c61\uff0c\u5c31\u503c\u5f97\u4e8b\u5148\u521b\u5efa\u6240\u9700\u7684Pen\u548cBrush\u5bf9\u8c61\uff0c\u5e76\u5728\u7a97\u53e3\u7684\u6574\u4e2a\u751f\u547d\u5468\u671f\u4e2d\u4fdd\u5b58\u4ed6\u4eec\u3002<\/span><\/h2>\n<p>\u8fd8\u53ef\u4ee5\u901a\u8fc7\u91cd\u5199OnRender()\u65b9\u6cd5\uff0c\u4f7f\u7528\u53ef\u89c6\u5316\u5bf9\u8c61\u6e32\u67d3\u81ea\u5b9a\u4e49\u7ed8\u56fe\u5143\u7d20\uff0c\u4f8b\u5982\u4e0b\u9762Rectangle\u5143\u7d20\u7528\u4e8e\u7ed8\u5236\u81ea\u8eab\u6e32\u67d3\u4ee3\u7801<\/p>\n<pre><code class=\"language-CSharp line-numbers\">protected override void OnRender(DrawingContext drawingContext)\n{\n    Pen pen=base.GetPen();\n    drawingContext.DrawRoundedRectangle(base.Fill,pen,this._rect,this.RadiusX,this.RadiusY);\n}\n<\/code><\/pre>\n<h2><span id=\"i-3\">\u5728\u5143\u7d20\u4e2d\u5c01\u88c5\u53ef\u89c6\u5316\u5bf9\u8c61<\/span><\/h2>\n<p>\u4e3a\u4e86\u663e\u793a\u53ef\u89c6\u5316\u5bf9\u8c61\uff0c\u8fd8\u9700\u8981\u501f\u52a9\u4e8e\u529f\u80fd\u5b8c\u5907\u7684WPF\u5143\u7d20\uff0cWPF\u5143\u7d20\u5c06\u53ef\u89c6\u5316\u5bf9\u8c61\u6dfb\u52a0\u5230\u53ef\u89c6\u5316\u6811\u79cd\u3002\u5355\u4e2a\u5143\u7d20\u5177\u6709\u663e\u793a\u4efb\u610f\u6570\u91cf\u53ef\u89c6\u5316\u5bf9\u8c61\u7684\u80fd\u529b\uff0c\u56e0\u6b64\uff0c\u53ef\u4ee5\u5f88\u5bb9\u6613\u5730\u521b\u5efa\u53ea\u5305\u542b\u4e00\u4e24\u4e2a\u5143\u7d20\uff0c\u4f46\u5374\u4e3b\u6d41\u4e86\u51e0\u5343\u4e2a\u53ef\u89c6\u5316\u5bf9\u8c61\u7684\u7a97\u53e3\u3002<br \/>\n\u4e3a\u5728\u5143\u7d20\u4e2d\u4e3b\u6d41\u53ef\u89c6\u5316\u5bf9\u8c61\uff0c\u9700\u8981\u6267\u884c\u4ee5\u4e0b\u4efb\u52a1\uff1a<br \/>\n&#8211; \u4e3a\u5143\u7d20\u8c03\u7528AddVisualChild()\u548cAddLogicalChild()\u65b9\u6cd5\u6765\u6ce8\u518c\u53ef\u89c6\u5316\u5bf9\u8c61\u3002\u4ece\u6280\u672f\u89d2\u5ea6\u770b\uff0c\u4e3a\u4e86\u663e\u793a\u53ef\u89c6\u5316\u5bf9\u8c61\uff0c\u4e0d\u9700\u8981\u6267\u884c\u8fd9\u4e9b\u4efb\u52a1\uff0c\u4f46\u4e3a\u4e86\u786e\u4fdd\u6b63\u786e\u8ddf\u8e2a\u53ef\u89c6\u5316\u5bf9\u8c61\u3001\u5728\u53ef\u89c6\u5316\u6811\u548c\u903b\u8f91\u6811\u4e2d\u663e\u793a\u53ef\u89c6\u5316\u5bf9\u8c61\u4ee5\u53ca\u4f7f\u7528\u5176\u4ed6WPF\u7279\u6027\uff08\u5982\u547d\u4e2d\u6d4b\u8bd5\uff09\uff0c\u9700\u8981\u6267\u884c\u8fd9\u4e9b\u64cd\u4f5c\u3002<br \/>\n&#8211; \u91cd\u5199VisualChildrenCount\u5c5e\u6027\u5e76\u8fd4\u56de\u5df2\u7ecf\u589e\u52a0\u4e86\u7684\u53ef\u89c6\u5316\u5bf9\u8c61\u7684\u6570\u91cf\u3002<br \/>\n&#8211; \u91cd\u5199GetViusalChild()\u65b9\u6cd5\uff0c\u5f53\u901a\u8fc7\u7d22\u5f15\u53f7\u8bf7\u6c42\u53ef\u89c6\u5316\u5bf9\u8c61\u65f6\uff0c\u6dfb\u52a0\u8fd4\u56de\u53ef\u89c6\u5316\u5bf9\u8c61\u6240\u9700\u7684\u4ee3\u7801\u3002<\/p>\n<p>\u5f53\u91cd\u5199VisualChildrenCount\u5c5e\u6027\u548cGetVisualChild()\u65b9\u6cd5\u65f6\uff0c\u672c\u8d28\u4e0a\u662f\u52ab\u6301\u4e86\u90a3\u4e2a\u5143\u7d20\u3002\u5982\u679c\u4f7f\u7528\u7684\u662f\u80fd\u591f\u5305\u542b\u5d4c\u5957\u5143\u7d20\u7684\u5185\u5bb9\u63a7\u4ef6\u3001\u88c5\u9970\u5143\u7d20\u6216\u9762\u677f\uff0c\u8fd9\u4e9b\u5143\u7d20\u5c06\u4e0d\u518d\u88ab\u6e32\u67d3\u3002\u4f8b\u5982\uff0c\u5982\u679c\u5728\u81ea\u5b9a\u4e49\u7a97\u53e3\u4e2d\u91cd\u5199\u4e86\u8fd9\u4e24\u4e2a\u65b9\u6cd5\uff0c\u5c31\u770b\u4e0d\u5230\u7a97\u53e3\u7684\u5176\u4ed6\u5185\u5bb9\uff0c\u53ea\u4f1a\u770b\u5230\u6dfb\u52a0\u7684\u53ef\u89c6\u5316\u5bf9\u8c61\u3002<br \/>\n\u56e0\u6b64\uff0c\u901a\u5e38\u521b\u5efa\u4e13\u7528\u7684\u81ea\u5b9a\u4e49\u7d2f\u6765\u5c01\u88c5\u5e0c\u671b\u663e\u793a\u7684\u53ef\u89c6\u5316\u5bf9\u8c61\u3002\u4f8b\u5982\uff0c\u5206\u6790\u4e0b\u56fe\u4e2d\u663e\u793a\u7684\u7a97\u53e3\uff0c\u8be5\u7a97\u53e3\u5141\u8bb8\u7528\u6237\u81ea\u5b9a\u4e49\u7684Canvas\u9762\u677f\u6dfb\u52a0\u6b63\u65b9\u5f62\uff08\u6bcf\u4e2a\u6b63\u65b9\u5f62\u662f\u53ef\u89c6\u5316\u5bf9\u8c61\uff09\u3002<br \/>\n<a class=\"wp-editor-md-post-content-link\" href=\"http:\/\/www.wayln.com\/wp-content\/uploads\/2021\/09\/wp_editor_md_a758999cf6d7859eb157c256d3fa204f.jpg\"><img decoding=\"async\" src=\"http:\/\/www.wayln.com\/wp-content\/uploads\/2021\/09\/wp_editor_md_a758999cf6d7859eb157c256d3fa204f.jpg\" alt=\"\" \/><\/a><\/p>\n<pre><code class=\"language-CSharp line-numbers\"> class DrawingCanvas:Canvas\n    {\n        private List&lt;Visual&gt; visuals = new List&lt;Visual&gt;();\n        protected override int VisualChildrenCount =&gt; visuals.Count;\n        protected override Visual GetVisualChild(int index)\n        {\n            return visuals[index];\n        }\n        public void AddVisual(Visual visual)\n        {\n            visuals.Add(visual);\n            base.AddVisualChild(visual);\n            base.AddLogicalChild(visual);\n        }\n        public void DeletedVisual(Visual visual)\n        {\n            visuals.Remove(visual);\n            base.RemoveVisualChild(visual);\n            base.RemoveLogicalChild(visual);\n        }\n    }\n<\/code><\/pre>\n<pre><code class=\"language-XML line-numbers\">    &lt;local:DrawingCanvas x:Name=\"drawingSurface\" Background=\"White\" ClipToBounds=\"True\" MouseLeftButtonDown=\"drawingSurface_MouseLeftButtonDown\"\n MouseLeftButtonUp=\"drawingSurface_MouseLeftButtonUp\" MouseMove=\"drawingSurface_MouseMove\"&gt;&lt;\/local:DrawingCanvas&gt;\n<\/code><\/pre>\n<pre><code class=\"language-CSharp line-numbers\">   private void drawingSurface_MouseLeftButtonDown(object sender, MouseButtonEventArgs e)\n        {\n            Point pointClicked = e.GetPosition(drawingSurface);\n            DrawingVisual visual = new DrawingVisual();\n            DrawingSquare(visual, pointClicked, false);\n            drawingSurface.AddVisual(visual);\n\n\n        }\n        Brush drawingBrush = Brushes.AliceBlue;\n        Brush selectedDrawingBrush = Brushes.LightGoldenrodYellow;\n        Pen drawingPen = new Pen(Brushes.SteelBlue, 3);\n        Size squareSize = new Size(30, 30);\n        private void DrawingSquare(DrawingVisual visual,Point topLeftCorner,bool isSelected)\n        {\n            using (DrawingContext dc = visual.RenderOpen())\n            {\n                Brush brush = drawingBrush;\n                dc.DrawRectangle(brush, drawingPen, new Rect(topLeftCorner, squareSize));\n                dc.DrawText(new FormattedText(\"hjefef\",CultureInfo.CurrentCulture,FlowDirection.LeftToRight,new Typeface(\"\u534e\u6587\u884c\u6977\"),12,Brushes.Black), topLeftCorner);\n            }\n        }\n        private void drawingSurface_MouseLeftButtonUp(object sender, MouseButtonEventArgs e)\n        {\n\n        }\n\n        private void drawingSurface_MouseMove(object sender, MouseEventArgs e)\n        {\n\n        }\n<\/code><\/pre>\n<h2><span id=\"i-4\">\u547d\u4e2d\u6d4b\u8bd5<\/span><\/h2>\n","protected":false},"excerpt":{"rendered":"<p>Contents1 \u53ef\u89c6\u5316\u5bf9\u8c611.1 \u7ed8\u5236\u53ef\u89c6\u5316\u5bf9\u8c611.2 \u4e00\u65e6\u5173\u95edDrawingContext\u5bf9\u8c61\uff0c\u5c31\u4e0d\u80fd\u518d [&hellip;]<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"closed","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[4,35,36,2],"tags":[],"class_list":["post-935","post","type-post","status-publish","format-standard","hentry","category-c","category-wpf","category-2"],"_links":{"self":[{"href":"https:\/\/www.wayln.com\/index.php?rest_route=\/wp\/v2\/posts\/935","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.wayln.com\/index.php?rest_route=\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.wayln.com\/index.php?rest_route=\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.wayln.com\/index.php?rest_route=\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/www.wayln.com\/index.php?rest_route=%2Fwp%2Fv2%2Fcomments&post=935"}],"version-history":[{"count":3,"href":"https:\/\/www.wayln.com\/index.php?rest_route=\/wp\/v2\/posts\/935\/revisions"}],"predecessor-version":[{"id":938,"href":"https:\/\/www.wayln.com\/index.php?rest_route=\/wp\/v2\/posts\/935\/revisions\/938"}],"wp:attachment":[{"href":"https:\/\/www.wayln.com\/index.php?rest_route=%2Fwp%2Fv2%2Fmedia&parent=935"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.wayln.com\/index.php?rest_route=%2Fwp%2Fv2%2Fcategories&post=935"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.wayln.com\/index.php?rest_route=%2Fwp%2Fv2%2Ftags&post=935"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}