{"id":34236,"date":"2024-11-25T11:11:21","date_gmt":"2024-11-25T03:11:21","guid":{"rendered":"https:\/\/fwq.ai\/blog\/34236\/"},"modified":"2024-11-25T11:11:21","modified_gmt":"2024-11-25T03:11:21","slug":"%e6%89%8b%e6%8a%8a%e6%89%8b%e6%95%99%e4%bd%a0%e5%9c%a8%e5%be%ae%e4%bf%a1%e5%b0%8f%e7%a8%8b%e5%ba%8f%e4%b8%ad%e4%bd%bf%e7%94%a8canvas%e7%bb%98%e5%88%b6%e5%a4%a9%e6%b0%94%e6%8a%98%e7%ba%bf%e5%9b%be","status":"publish","type":"post","link":"https:\/\/fwq.ai\/blog\/34236\/","title":{"rendered":"\u624b\u628a\u624b\u6559\u4f60\u5728\u5fae\u4fe1\u5c0f\u7a0b\u5e8f\u4e2d\u4f7f\u7528canvas\u7ed8\u5236\u5929\u6c14\u6298\u7ebf\u56fe\uff08\u9644\u4ee3\u7801\uff09"},"content":{"rendered":"<p>\u5fae\u4fe1\u5c0f\u7a0b\u5e8f\u4e2d\u5982\u4f55\u7ed8\u5236\u5929\u6c14\u6298\u7ebf\u56fe\uff1f\u4e0b\u9762\u672c\u7bc7\u6587\u7ae0\u5c31\u6765\u7ed9\u5927\u5bb6\u4ecb\u7ecd\u4e00\u4e0b\u5728\u5fae\u4fe1\u5c0f\u7a0b\u5e8f\u4e2d\u4f7f\u7528canvas\u7ed8\u5236\u5929\u6c14\u6298\u7ebf\u56fe\u7684\u65b9\u6cd5\uff0c\u4ee5\u53ca\u4f7f\u7528\u4e09\u9636\u8d1d\u585e\u5c14\u66f2\u7ebf\u62df\u5408\u6e29\u5ea6\u70b9\uff0c\u4f7f\u4e4b\u53d8\u5f97\u5706\u6ed1\uff0c\u66f2\u7ebf\u5e95\u90e8\u6709\u80cc\u666f\u8272\uff0c\u5e0c\u671b\u5bf9\u5927\u5bb6\u6709\u6240\u5e2e\u52a9\uff01<\/p>\n<p><img decoding=\"async\" src=\"https:\/\/img.php.cn\/upload\/article\/000\/000\/024\/62064f34797c3595.jpg\" class=\"aligncenter\" title=\"\u624b\u628a\u624b\u6559\u4f60\u5728\u5fae\u4fe1\u5c0f\u7a0b\u5e8f\u4e2d\u4f7f\u7528canvas\u7ed8\u5236\u5929\u6c14\u6298\u7ebf\u56fe\uff08\u9644\u4ee3\u7801\uff09\u63d2\u56fe\" alt=\"\u624b\u628a\u624b\u6559\u4f60\u5728\u5fae\u4fe1\u5c0f\u7a0b\u5e8f\u4e2d\u4f7f\u7528canvas\u7ed8\u5236\u5929\u6c14\u6298\u7ebf\u56fe\uff08\u9644\u4ee3\u7801\uff09\u63d2\u56fe\" \/><\/p>\n<h2><strong>\u6298\u7ebf<\/strong><\/h2>\n<p><strong>\u6548\u679c\u56fe\uff1a<\/strong><\/p>\n<p><img decoding=\"async\" src=\"https:\/\/img.php.cn\/upload\/image\/654\/425\/428\/1644580424220403.gif\" class=\"aligncenter\" title=\"\u624b\u628a\u624b\u6559\u4f60\u5728\u5fae\u4fe1\u5c0f\u7a0b\u5e8f\u4e2d\u4f7f\u7528canvas\u7ed8\u5236\u5929\u6c14\u6298\u7ebf\u56fe\uff08\u9644\u4ee3\u7801\uff09\u63d2\u56fe1\" alt=\"\u624b\u628a\u624b\u6559\u4f60\u5728\u5fae\u4fe1\u5c0f\u7a0b\u5e8f\u4e2d\u4f7f\u7528canvas\u7ed8\u5236\u5929\u6c14\u6298\u7ebf\u56fe\uff08\u9644\u4ee3\u7801\uff09\u63d2\u56fe1\" \/><\/p>\n<p><strong>\u81ea\u5b9a\u4e49\u7ec4\u4ef6 line-chart<\/strong><\/p>\n<pre>&lt;canvas&gt;&lt;\/canvas&gt;<\/pre>\n<p> \u767b\u5f55\u540e\u590d\u5236 <\/p>\n<pre>Component({\n&nbsp;&nbsp;externalClasses:&nbsp;['line-class'],\n&nbsp;&nbsp;properties:&nbsp;{\n&nbsp;&nbsp;&nbsp;&nbsp;width:&nbsp;String,\n&nbsp;&nbsp;&nbsp;&nbsp;height:&nbsp;String,\n&nbsp;&nbsp;&nbsp;&nbsp;data:&nbsp;Array,\n&nbsp;&nbsp;},\n&nbsp;&nbsp;observers:&nbsp;{\n&nbsp;&nbsp;&nbsp;&nbsp;width()&nbsp;{\n&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;\/\/&nbsp;\u8fd9\u91cc\u76d1\u542c&nbsp;width&nbsp;\u53d8\u5316\u91cd\u7ed8&nbsp;canvas\n&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;\/\/&nbsp;\u52a8\u6001\u4f20\u5165&nbsp;width&nbsp;\u597d\u50cf\u53ea\u80fd\u8fd9\u6837\u4e86..\n&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;const&nbsp;query&nbsp;=&nbsp;this.createSelectorQuery();\n&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;query\n&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;.select('#line')\n&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;.fields({&nbsp;node:&nbsp;true,&nbsp;size:&nbsp;true&nbsp;})\n&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;.exec(res&nbsp;=&amp;gt;&nbsp;{\n&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;const&nbsp;canvas&nbsp;=&nbsp;res[0].node;\n&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;const&nbsp;ctx&nbsp;=&nbsp;canvas.getContext('2d');\n&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;const&nbsp;width&nbsp;=&nbsp;res[0].width;&nbsp;\/\/&nbsp;\u753b\u5e03\u5bbd\u5ea6\n&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;const&nbsp;height&nbsp;=&nbsp;res[0].height;&nbsp;\/\/&nbsp;\u753b\u5e03\u9ad8\u5ea6\n\n&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;console.log(`\u5bbd\u5ea6:&nbsp;${width},&nbsp;\u9ad8\u5ea6:&nbsp;${height}`);\n\n&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;const&nbsp;dpr&nbsp;=&nbsp;wx.getSystemInfoSync().pixelRatio;\n&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;canvas.width&nbsp;=&nbsp;width&nbsp;*&nbsp;dpr;\n&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;canvas.height&nbsp;=&nbsp;height&nbsp;*&nbsp;dpr;\n&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;ctx.scale(dpr,&nbsp;dpr);\n\n&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;\/\/&nbsp;\u5f00\u59cb\u7ed8\u56fe\n&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;this.drawLine(ctx,&nbsp;width,&nbsp;height,&nbsp;this.data.data);\n&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;});\n&nbsp;&nbsp;&nbsp;&nbsp;},\n&nbsp;&nbsp;},\n&nbsp;&nbsp;methods:&nbsp;{\n&nbsp;&nbsp;&nbsp;&nbsp;drawLine(ctx,&nbsp;width,&nbsp;height,&nbsp;data)&nbsp;{\n&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;const&nbsp;Max&nbsp;=&nbsp;Math.max(...data);\n&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;const&nbsp;Min&nbsp;=&nbsp;Math.min(...data);\n\n&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;\/\/&nbsp;\u628a&nbsp;canvas&nbsp;\u7684\u5bbd\u5ea6,&nbsp;\u9ad8\u5ea6\u6309\u4e00\u5b9a\u89c4\u5219\u5e73\u5206\n&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;const&nbsp;startX&nbsp;=&nbsp;width&nbsp;\/&nbsp;(data.length&nbsp;*&nbsp;2),&nbsp;\/\/&nbsp;\u8d77\u59cb\u70b9\u7684\u6a2a\u5750\u6807&nbsp;X\n&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;baseY&nbsp;=&nbsp;height&nbsp;*&nbsp;0.9,&nbsp;\/\/&nbsp;\u57fa\u7ebf\u7eb5\u5750\u6807&nbsp;Y\n&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;diffX&nbsp;=&nbsp;width&nbsp;\/&nbsp;data.length,\n&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;diffY&nbsp;=&nbsp;(height&nbsp;*&nbsp;0.7)&nbsp;\/&nbsp;(Max&nbsp;-&nbsp;Min);&nbsp;\/\/&nbsp;\u9ad8\u5ea6\u9884\u7559&nbsp;0.2&nbsp;\u5199\u6e29\u5ea6\n\n&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;ctx.beginPath();\n&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;ctx.textAlign&nbsp;=&nbsp;'center';\n&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;ctx.font&nbsp;=&nbsp;'13px&nbsp;Microsoft&nbsp;YaHei';\n&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;ctx.lineWidth&nbsp;=&nbsp;2;\n&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;ctx.strokeStyle&nbsp;=&nbsp;'#ABDCFF';\n\n&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;\/\/&nbsp;\u753b\u6298\u7ebf\u56fe\u7684\u7ebf\n&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;data.forEach((item,&nbsp;index)&nbsp;=&amp;gt;&nbsp;{\n&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;const&nbsp;x&nbsp;=&nbsp;startX&nbsp;+&nbsp;diffX&nbsp;*&nbsp;index,\n&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;y&nbsp;=&nbsp;baseY&nbsp;-&nbsp;(item&nbsp;-&nbsp;Min)&nbsp;*&nbsp;diffY;\n\n&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;ctx.fillText(`${item}\u00b0`,&nbsp;x,&nbsp;y&nbsp;-&nbsp;10);\n&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;ctx.lineTo(x,&nbsp;y);\n&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;});\n&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;ctx.stroke();\n\n&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;\/\/&nbsp;\u753b\u6298\u7ebf\u56fe\u80cc\u666f\n&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;ctx.lineTo(startX&nbsp;+&nbsp;(data.length&nbsp;-&nbsp;1)&nbsp;*&nbsp;diffX,&nbsp;baseY);&nbsp;\/\/&nbsp;\u57fa\u7ebf\u7ec8\u70b9\n&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;ctx.lineTo(startX,&nbsp;baseY);&nbsp;\/\/&nbsp;\u57fa\u7ebf\u8d77\u70b9\n&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;const&nbsp;lingrad&nbsp;=&nbsp;ctx.createLinearGradient(0,&nbsp;0,&nbsp;0,&nbsp;height&nbsp;*&nbsp;0.7);\n&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;lingrad.addColorStop(0,&nbsp;'rgba(255,255,255,0.9)');\n&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;lingrad.addColorStop(1,&nbsp;'rgba(171,220,255,0)');\n&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;ctx.fillStyle&nbsp;=&nbsp;lingrad;\n&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;ctx.fill();\n\n&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;\/\/&nbsp;\u753b\u6298\u7ebf\u56fe\u4e0a\u7684\u5c0f\u5706\u70b9\n&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;ctx.beginPath();\n&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;data.forEach((item,&nbsp;index)&nbsp;=&amp;gt;&nbsp;{\n&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;const&nbsp;x&nbsp;=&nbsp;startX&nbsp;+&nbsp;diffX&nbsp;*&nbsp;index,\n&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;y&nbsp;=&nbsp;baseY&nbsp;-&nbsp;(item&nbsp;-&nbsp;Min)&nbsp;*&nbsp;diffY;\n\n&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;ctx.moveTo(x,&nbsp;y);\n&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;ctx.arc(x,&nbsp;y,&nbsp;3,&nbsp;0,&nbsp;2&nbsp;*&nbsp;Math.PI);\n&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;});\n&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;ctx.fillStyle&nbsp;=&nbsp;'#0396FF';\n&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;ctx.fill();\n&nbsp;&nbsp;&nbsp;&nbsp;},\n&nbsp;&nbsp;},\n});<\/pre>\n<p> \u767b\u5f55\u540e\u590d\u5236 <\/p>\n<p>data \u5c31\u662f\u6e29\u5ea6\u6570\u7ec4\uff0c\u5982 [1, 2, &#8230;]<\/p>\n<p>\u56e0\u4e3a\u4e0d\u77e5\u9053\u6e29\u5ea6\u6570\u503c\u6709\u591a\u5c11\u4e2a\uff0c\u56e0\u6b64\u8fd9\u91cc\u7684 width \u52a8\u6001\u4f20\u5165<\/p>\n<p>\u6709\u4e2a\u5c0f\u95ee\u9898\uff0c\u5c31\u662f\u5bbd\u5ea6\u8fc7\u5927\u7684\u8bdd\u771f\u673a\u4e0d\u4f1a\u663e\u793a&#8230;<\/p>\n<pre>&nbsp;\/\/&nbsp;\u83b7\u53d6&nbsp;scroll-view&nbsp;\u7684\u603b\u5bbd\u5ea6\n&nbsp;wx.createSelectorQuery()\n&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;.select('.hourly')\n&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;.boundingClientRect(rect&nbsp;=&amp;gt;&nbsp;{\n&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;this.setData({\n&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;scrollWidth:&nbsp;rect.right&nbsp;-&nbsp;rect.left,\n&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;});\n&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;})\n&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;.exec();<\/pre>\n<p> \u767b\u5f55\u540e\u590d\u5236 <\/p>\n<pre>&lt;view&gt;\u5c0f\u65f6\u6982\u8ff0&lt;\/view&gt;&lt;scroll-view&gt;\n&nbsp;&nbsp;&nbsp;&nbsp;&lt;view&gt;\n&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&lt;view&gt;{{item}}&lt;\/view&gt;\n&nbsp;&nbsp;&nbsp;&nbsp;&lt;\/view&gt;\n&nbsp;&nbsp;&nbsp;&nbsp;&lt;line-chart&gt;&lt;\/line-chart&gt;&lt;\/scroll-view&gt;<\/pre>\n<p> \u767b\u5f55\u540e\u590d\u5236 <\/p>\n<p>\u8fd9\u91cc\u5199 scroll-x \u548c scroll-y\uff0c\u8981\u4e0d\u4f1a\u51fa\u73b0\u7edd\u5bf9\u5b9a\u4f4d\u504f\u79fb\u7684\u95ee\u9898\uff0c\u4e5f\u4e0d\u77e5\u9053\u4e3a\u4ec0\u4e48&nbsp;<\/p>\n<p><img decoding=\"async\" src=\"https:\/\/img.php.cn\/upload\/image\/511\/676\/637\/1644580429156813.gif\" class=\"aligncenter\" title=\"\u624b\u628a\u624b\u6559\u4f60\u5728\u5fae\u4fe1\u5c0f\u7a0b\u5e8f\u4e2d\u4f7f\u7528canvas\u7ed8\u5236\u5929\u6c14\u6298\u7ebf\u56fe\uff08\u9644\u4ee3\u7801\uff09\u63d2\u56fe2\" alt=\"\u624b\u628a\u624b\u6559\u4f60\u5728\u5fae\u4fe1\u5c0f\u7a0b\u5e8f\u4e2d\u4f7f\u7528canvas\u7ed8\u5236\u5929\u6c14\u6298\u7ebf\u56fe\uff08\u9644\u4ee3\u7801\uff09\u63d2\u56fe2\" \/><\/p>\n<pre>.scroll&nbsp;{\n&nbsp;&nbsp;position:&nbsp;relative;\n&nbsp;&nbsp;height:&nbsp;150px;\n&nbsp;&nbsp;width:&nbsp;100%;\n}\n\n.hourly&nbsp;{\n&nbsp;&nbsp;display:&nbsp;flex;\n&nbsp;&nbsp;height:&nbsp;150px;\n&nbsp;&nbsp;position:&nbsp;absolute;\n&nbsp;&nbsp;top:&nbsp;0;\n}\n\n.hourly&nbsp;&amp;gt;&nbsp;view&nbsp;{\n&nbsp;&nbsp;min-width:&nbsp;3.5em;\n&nbsp;&nbsp;text-align:&nbsp;center;\n}\n\n.line&nbsp;{&nbsp;\/\/&nbsp;\u6298\u7ebf\u56fe\u7edd\u5bf9\u5b9a\u4f4d\u5230\u5e95\u90e8\n&nbsp;&nbsp;position:&nbsp;absolute;\n&nbsp;&nbsp;bottom:&nbsp;0;\n}<\/pre>\n<p> \u767b\u5f55\u540e\u590d\u5236 <\/p>\n<p>\u8fd9\u91cc\u4f7f\u7528\u7edd\u5bf9\u5b9a\u4f4d\u5176\u5b9e\u662f\u60f3\u6a21\u62df\u58a8\u8ff9\u5929\u6c14\u8fd9\u79cd\u6298\u7ebf\u56fe\u548c\u6bcf\u4e00\u5929\u5728\u4e00\u4e2a\u5757\u5185\u7684\u6548\u679c\uff0c\u6240\u4ee5 hourly \u8981\u548c scroll-view \u7b49\u9ad8\uff0ccanvas \u9700\u8981\u5b9a\u4f4d\u4e00\u4e0b<\/p>\n<p>\u4e3b\u8981\u662f\u4e0d\u77e5\u9053\u58a8\u8ff9\u5929\u6c14\u600e\u4e48\u5b9e\u73b0\u7684\uff0c\u53ea\u80fd\u6682\u65f6\u8fd9\u6837<\/p>\n<p><img decoding=\"async\" src=\"https:\/\/img.php.cn\/upload\/image\/592\/948\/548\/1644580434229599.gif\" class=\"aligncenter\" title=\"\u624b\u628a\u624b\u6559\u4f60\u5728\u5fae\u4fe1\u5c0f\u7a0b\u5e8f\u4e2d\u4f7f\u7528canvas\u7ed8\u5236\u5929\u6c14\u6298\u7ebf\u56fe\uff08\u9644\u4ee3\u7801\uff09\u63d2\u56fe3\" alt=\"\u624b\u628a\u624b\u6559\u4f60\u5728\u5fae\u4fe1\u5c0f\u7a0b\u5e8f\u4e2d\u4f7f\u7528canvas\u7ed8\u5236\u5929\u6c14\u6298\u7ebf\u56fe\uff08\u9644\u4ee3\u7801\uff09\u63d2\u56fe3\" \/><\/p>\n<h2><strong>\u4e09\u9636\u8d1d\u585e\u5c14\u66f2\u7ebf<\/strong><\/h2>\n<p><strong>\u6548\u679c\u56fe<\/strong><\/p>\n<p><img decoding=\"async\" src=\"https:\/\/img.php.cn\/upload\/image\/340\/987\/932\/1644580440641472.gif\" class=\"aligncenter\" title=\"\u624b\u628a\u624b\u6559\u4f60\u5728\u5fae\u4fe1\u5c0f\u7a0b\u5e8f\u4e2d\u4f7f\u7528canvas\u7ed8\u5236\u5929\u6c14\u6298\u7ebf\u56fe\uff08\u9644\u4ee3\u7801\uff09\u63d2\u56fe4\" alt=\"\u624b\u628a\u624b\u6559\u4f60\u5728\u5fae\u4fe1\u5c0f\u7a0b\u5e8f\u4e2d\u4f7f\u7528canvas\u7ed8\u5236\u5929\u6c14\u6298\u7ebf\u56fe\uff08\u9644\u4ee3\u7801\uff09\u63d2\u56fe4\" \/><\/p>\n<p>emmm\uff0c\u597d\u50cf\u5e76\u4e0d\u600e\u4e48\u5706\u6ed1&nbsp;<\/p>\n<p><strong>\u8ba1\u7b97\u63a7\u5236\u70b9<\/strong><\/p>\n<p>\u9996\u5148\u5199\u4e00\u4e2a\u70b9\u7c7b<\/p>\n<pre>class&nbsp;Point&nbsp;{\n&nbsp;&nbsp;constructor(x,&nbsp;y)&nbsp;{\n&nbsp;&nbsp;&nbsp;&nbsp;this.x&nbsp;=&nbsp;x;\n&nbsp;&nbsp;&nbsp;&nbsp;this.y&nbsp;=&nbsp;y;\n&nbsp;&nbsp;}\n}<\/pre>\n<p> \u767b\u5f55\u540e\u590d\u5236 <\/p>\n<blockquote><p>\n  Canvas\u8d1d\u585e\u5c14\u66f2\u7ebf\u7ed8\u5236\u5de5\u5177 (karlew.com)http:\/\/wx.karlew.com\/canvas\/bezier\/\n<\/p><\/blockquote>\n<p>\u901a\u8fc7\u4e0a\u9762\u8fd9\u4e2a\u7f51\u7ad9\u53ef\u4ee5\u77e5\u9053\u4e09\u9636\u8d1d\u585e\u5c14\u66f2\u7ebf\u5404\u4e2a\u53c2\u6570\u7684\u610f\u4e49<\/p>\n<p><img decoding=\"async\" src=\"https:\/\/img.php.cn\/upload\/image\/709\/271\/454\/1644580444186924.gif\" class=\"aligncenter\" title=\"\u624b\u628a\u624b\u6559\u4f60\u5728\u5fae\u4fe1\u5c0f\u7a0b\u5e8f\u4e2d\u4f7f\u7528canvas\u7ed8\u5236\u5929\u6c14\u6298\u7ebf\u56fe\uff08\u9644\u4ee3\u7801\uff09\u63d2\u56fe5\" alt=\"\u624b\u628a\u624b\u6559\u4f60\u5728\u5fae\u4fe1\u5c0f\u7a0b\u5e8f\u4e2d\u4f7f\u7528canvas\u7ed8\u5236\u5929\u6c14\u6298\u7ebf\u56fe\uff08\u9644\u4ee3\u7801\uff09\u63d2\u56fe5\" \/><\/p>\n<p>\u4e5f\u5c31\u662f\u4f7f\u7528 bezierCurveTo \u7684\u65f6\u5019\u6700\u540e\u4e00\u4e2a\u70b9\u662f\u4e0b\u4e00\u4e2a\u70b9\uff0c\u524d\u4e24\u4e2a\u662f\u63a7\u5236\u70b9<\/p>\n<blockquote>\n<p>\u63a7\u5236\u70b9\u7684\u8ba1\u7b97\u53c2\u8003: \u8d1d\u585e\u5c14\u66f2\u7ebf\u63a7\u5236\u70b9\u786e\u5b9a\u7684\u65b9\u6cd5 &#8211; \u767e\u5ea6\u6587\u5e93<\/p>\n<p>https:\/\/wenku.baidu.com\/view\/c790f8d46bec0975f565e211.html<\/p>\n<\/blockquote>\n<p>\u6d53\u7f29\u4e00\u4e0b\u5c31\u662f<\/p>\n<p><img decoding=\"async\" src=\"https:\/\/img.php.cn\/upload\/image\/445\/142\/643\/1644580448520949.gif\" class=\"aligncenter\" title=\"\u624b\u628a\u624b\u6559\u4f60\u5728\u5fae\u4fe1\u5c0f\u7a0b\u5e8f\u4e2d\u4f7f\u7528canvas\u7ed8\u5236\u5929\u6c14\u6298\u7ebf\u56fe\uff08\u9644\u4ee3\u7801\uff09\u63d2\u56fe6\" alt=\"\u624b\u628a\u624b\u6559\u4f60\u5728\u5fae\u4fe1\u5c0f\u7a0b\u5e8f\u4e2d\u4f7f\u7528canvas\u7ed8\u5236\u5929\u6c14\u6298\u7ebf\u56fe\uff08\u9644\u4ee3\u7801\uff09\u63d2\u56fe6\" \/><\/p>\n<p>\u8fd9\u91cc\u7684 a \u548c b \u53ef\u4ee5\u662f\u4efb\u610f\u6b63\u6570<\/p>\n<p>\u56e0\u6b64\u5b9a\u4e49\u4e00\u4e2a\u8ba1\u7b97\u67d0\u70b9\u7684\u63a7\u5236\u70b9 A \u548c B \u7684\u65b9\u6cd5<\/p>\n<pre>\/**\n&nbsp;*&nbsp;\u8ba1\u7b97\u5f53\u524d\u70b9\u7684\u8d1d\u585e\u5c14\u66f2\u7ebf\u63a7\u5236\u70b9\n&nbsp;*&nbsp;@param&nbsp;{Point}&nbsp;previousPoint:&nbsp;\u524d\u4e00\u4e2a\u70b9\n&nbsp;*&nbsp;@param&nbsp;{Point}&nbsp;currentPoint:&nbsp;\u5f53\u524d\u70b9\n&nbsp;*&nbsp;@param&nbsp;{Point}&nbsp;nextPoint1:&nbsp;\u4e0b\u4e00\u4e2a\u70b9\n&nbsp;*&nbsp;@param&nbsp;{Point}&nbsp;nextPoint2:&nbsp;\u4e0b\u4e0b\u4e2a\u70b9\n&nbsp;*&nbsp;@param&nbsp;{Number}&nbsp;scale:&nbsp;\u7cfb\u6570\n&nbsp;*\/\ncalcBezierControlPoints(\n&nbsp;&nbsp;previousPoint,\n&nbsp;&nbsp;currentPoint,\n&nbsp;&nbsp;nextPoint1,\n&nbsp;&nbsp;nextPoint2,\n&nbsp;&nbsp;scale&nbsp;=&nbsp;0.25\n)&nbsp;{\n&nbsp;&nbsp;let&nbsp;x&nbsp;=&nbsp;currentPoint.x&nbsp;+&nbsp;scale&nbsp;*&nbsp;(nextPoint1.x&nbsp;-&nbsp;previousPoint.x);\n&nbsp;&nbsp;let&nbsp;y&nbsp;=&nbsp;currentPoint.y&nbsp;+&nbsp;scale&nbsp;*&nbsp;(nextPoint1.y&nbsp;-&nbsp;previousPoint.y);\n\n&nbsp;&nbsp;const&nbsp;controlPointA&nbsp;=&nbsp;new&nbsp;Point(x,&nbsp;y);&nbsp;\/\/&nbsp;\u63a7\u5236\u70b9&nbsp;A\n\n&nbsp;&nbsp;x&nbsp;=&nbsp;nextPoint1.x&nbsp;-&nbsp;scale&nbsp;*&nbsp;(nextPoint2.x&nbsp;-&nbsp;currentPoint.x);\n&nbsp;&nbsp;y&nbsp;=&nbsp;nextPoint1.y&nbsp;-&nbsp;scale&nbsp;*&nbsp;(nextPoint2.y&nbsp;-&nbsp;currentPoint.y);\n\n&nbsp;&nbsp;const&nbsp;controlPointB&nbsp;=&nbsp;new&nbsp;Point(x,&nbsp;y);&nbsp;\/\/&nbsp;\u63a7\u5236\u70b9&nbsp;B\n\n&nbsp;&nbsp;return&nbsp;{&nbsp;controlPointA,&nbsp;controlPointB&nbsp;};\n}<\/pre>\n<p> \u767b\u5f55\u540e\u590d\u5236 <\/p>\n<p>\u8fd9\u91cc scale \u5c31\u662f a \u548c b\uff0c\u4e0d\u8fc7\u5c06\u5b83\u4eec\u7684\u53d6\u503c\u76f8\u7b49<\/p>\n<p>\u4f46\u662f\u7b2c\u4e00\u4e2a\u70b9\u6ca1\u6709 previousPoint\uff0c\u5012\u6570\u7b2c\u4e8c\u4e2a\u70b9\u6ca1\u6709 nextPoint2<\/p>\n<p>\u56e0\u6b64\u5f53\u70b9\u662f\u7b2c\u4e00\u4e2a\u7684\u65f6\u5019\uff0c\u4f7f\u7528 currentPoint \u4ee3\u66ff previousPoint<\/p>\n<p>\u5f53\u5012\u6570\u7b2c\u4e8c\u4e2a\u70b9\u7684\u65f6\u5019\uff0c\u4f7f\u7528 nextPoint1 \u4ee3\u66ff nextPoint2<\/p>\n<p><img decoding=\"async\" src=\"https:\/\/img.php.cn\/upload\/image\/108\/951\/548\/1644580458300431.gif\" class=\"aligncenter\" title=\"\u624b\u628a\u624b\u6559\u4f60\u5728\u5fae\u4fe1\u5c0f\u7a0b\u5e8f\u4e2d\u4f7f\u7528canvas\u7ed8\u5236\u5929\u6c14\u6298\u7ebf\u56fe\uff08\u9644\u4ee3\u7801\uff09\u63d2\u56fe7\" alt=\"\u624b\u628a\u624b\u6559\u4f60\u5728\u5fae\u4fe1\u5c0f\u7a0b\u5e8f\u4e2d\u4f7f\u7528canvas\u7ed8\u5236\u5929\u6c14\u6298\u7ebf\u56fe\uff08\u9644\u4ee3\u7801\uff09\u63d2\u56fe7\" \/><\/p>\n<p>\u81f3\u4e8e\u6700\u540e\u4e00\u4e2a\u70b9\uff0c\u4e0d\u9700\u8981\u505a\u4efb\u4f55\u4e8b\uff0c\u56e0\u4e3a bezierCurveTo \u7b2c\u4e09\u4e2a\u53c2\u6570\u5c31\u662f\u4e0b\u4e00\u4e2a\u70b9\uff0c\u53ea\u9700\u8981\u63d0\u4f9b\u5750\u6807\u5c31\u80fd\u8fde\u8d77\u6765\uff0c\u4e0d\u9700\u8981\u8ba1\u7b97\u63a7\u5236\u70b9<\/p>\n<p>\u56e0\u6b64\u7ed8\u5236\u4e09\u9636\u8d1d\u585e\u5c14\u66f2\u7ebf\u7684\u65b9\u6cd5\uff1a<\/p>\n<pre>\/**\n&nbsp;*&nbsp;\u7ed8\u5236\u8d1d\u585e\u5c14\u66f2\u7ebf\n&nbsp;*&nbsp;ctx.bezierCurveTo(\u63a7\u5236\u70b91,&nbsp;\u63a7\u5236\u70b92,&nbsp;\u5f53\u524d\u70b9);\n&nbsp;*\/\ndrawBezierLine(ctx,&nbsp;data,&nbsp;options)&nbsp;{\n&nbsp;&nbsp;const&nbsp;{&nbsp;startX,&nbsp;diffX,&nbsp;baseY,&nbsp;diffY,&nbsp;Min&nbsp;}&nbsp;=&nbsp;options;\n\n&nbsp;&nbsp;ctx.beginPath();\n&nbsp;&nbsp;\/\/&nbsp;\u5148\u79fb\u52a8\u5230\u7b2c\u4e00\u4e2a\u70b9\n&nbsp;&nbsp;ctx.moveTo(startX,&nbsp;baseY&nbsp;-&nbsp;(data[0]&nbsp;-&nbsp;Min)&nbsp;*&nbsp;diffY);\n\n&nbsp;&nbsp;data.forEach((e,&nbsp;i)&nbsp;=&amp;gt;&nbsp;{\n&nbsp;&nbsp;&nbsp;&nbsp;let&nbsp;curPoint,&nbsp;prePoint,&nbsp;nextPoint1,&nbsp;nextPoint2,&nbsp;x,&nbsp;y;\n\n&nbsp;&nbsp;&nbsp;&nbsp;\/\/&nbsp;\u5f53\u524d\u70b9\n&nbsp;&nbsp;&nbsp;&nbsp;x&nbsp;=&nbsp;startX&nbsp;+&nbsp;diffX&nbsp;*&nbsp;i;\n&nbsp;&nbsp;&nbsp;&nbsp;y&nbsp;=&nbsp;baseY&nbsp;-&nbsp;(e&nbsp;-&nbsp;Min)&nbsp;*&nbsp;diffY;\n&nbsp;&nbsp;&nbsp;&nbsp;curPoint&nbsp;=&nbsp;new&nbsp;Point(x,&nbsp;y);\n\n&nbsp;&nbsp;&nbsp;&nbsp;\/\/&nbsp;\u524d\u4e00\u4e2a\u70b9\n&nbsp;&nbsp;&nbsp;&nbsp;x&nbsp;=&nbsp;startX&nbsp;+&nbsp;diffX&nbsp;*&nbsp;(i&nbsp;-&nbsp;1);\n&nbsp;&nbsp;&nbsp;&nbsp;y&nbsp;=&nbsp;baseY&nbsp;-&nbsp;(data[i&nbsp;-&nbsp;1]&nbsp;-&nbsp;Min)&nbsp;*&nbsp;diffY;\n&nbsp;&nbsp;&nbsp;&nbsp;prePoint&nbsp;=&nbsp;new&nbsp;Point(x,&nbsp;y);\n\n&nbsp;&nbsp;&nbsp;&nbsp;\/\/&nbsp;\u4e0b\u4e00\u4e2a\u70b9\n&nbsp;&nbsp;&nbsp;&nbsp;x&nbsp;=&nbsp;startX&nbsp;+&nbsp;diffX&nbsp;*&nbsp;(i&nbsp;+&nbsp;1);\n&nbsp;&nbsp;&nbsp;&nbsp;y&nbsp;=&nbsp;baseY&nbsp;-&nbsp;(data[i&nbsp;+&nbsp;1]&nbsp;-&nbsp;Min)&nbsp;*&nbsp;diffY;\n&nbsp;&nbsp;&nbsp;&nbsp;nextPoint1&nbsp;=&nbsp;new&nbsp;Point(x,&nbsp;y);\n\n&nbsp;&nbsp;&nbsp;&nbsp;\/\/&nbsp;\u4e0b\u4e0b\u4e2a\u70b9\n&nbsp;&nbsp;&nbsp;&nbsp;x&nbsp;=&nbsp;startX&nbsp;+&nbsp;diffX&nbsp;*&nbsp;(i&nbsp;+&nbsp;2);\n&nbsp;&nbsp;&nbsp;&nbsp;y&nbsp;=&nbsp;baseY&nbsp;-&nbsp;(data[i&nbsp;+&nbsp;2]&nbsp;-&nbsp;Min)&nbsp;*&nbsp;diffY;\n&nbsp;&nbsp;&nbsp;&nbsp;nextPoint2&nbsp;=&nbsp;new&nbsp;Point(x,&nbsp;y);\n\n&nbsp;&nbsp;&nbsp;&nbsp;if&nbsp;(i&nbsp;===&nbsp;0)&nbsp;{\n&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;\/\/&nbsp;\u5982\u679c\u662f\u7b2c\u4e00\u4e2a\u70b9,&nbsp;\u5219\u524d\u4e00\u4e2a\u70b9\u7528\u5f53\u524d\u70b9\u4ee3\u66ff\n&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;prePoint&nbsp;=&nbsp;curPoint;\n&nbsp;&nbsp;&nbsp;&nbsp;}&nbsp;else&nbsp;if&nbsp;(i&nbsp;===&nbsp;data.length&nbsp;-&nbsp;2)&nbsp;{\n&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;\/\/&nbsp;\u5982\u679c\u662f\u5012\u6570\u7b2c\u4e8c\u4e2a\u70b9,&nbsp;\u5219\u4e0b\u4e0b\u4e2a\u70b9\u7528\u4e0b\u4e00\u4e2a\u70b9\u4ee3\u66ff\n&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;nextPoint2&nbsp;=&nbsp;nextPoint1;\n&nbsp;&nbsp;&nbsp;&nbsp;}&nbsp;else&nbsp;if&nbsp;(i&nbsp;===&nbsp;data.length&nbsp;-&nbsp;1)&nbsp;{\n&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;\/\/&nbsp;\u6700\u540e\u4e00\u4e2a\u70b9\u76f4\u63a5\u9000\u51fa\n&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;return;\n&nbsp;&nbsp;&nbsp;&nbsp;}\n\n&nbsp;&nbsp;&nbsp;&nbsp;const&nbsp;{&nbsp;controlPointA,&nbsp;controlPointB&nbsp;}&nbsp;=&nbsp;this.calcBezierControlPoints(\n&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;prePoint,\n&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;curPoint,\n&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;nextPoint1,\n&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;nextPoint2\n&nbsp;&nbsp;&nbsp;&nbsp;);\n\n&nbsp;&nbsp;&nbsp;&nbsp;ctx.bezierCurveTo(\n&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;controlPointA.x,\n&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;controlPointA.y,\n&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;controlPointB.x,\n&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;controlPointB.y,\n&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;nextPoint1.x,\n&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;nextPoint1.y\n&nbsp;&nbsp;&nbsp;&nbsp;);\n&nbsp;&nbsp;});\n\n&nbsp;&nbsp;ctx.stroke();\n},<\/pre>\n<p> \u767b\u5f55\u540e\u590d\u5236 <\/p>\n<p>\u3010\u76f8\u5173\u5b66\u4e60\u63a8\u8350\uff1a\u3011<\/p>\n<p>\u4ee5\u4e0a\u5c31\u662f\u624b\u628a\u624b\u6559\u4f60\u5728\u5fae\u4fe1\u5c0f\u7a0b\u5e8f\u4e2d\u4f7f\u7528canvas\u7ed8\u5236\u5929\u6c14\u6298\u7ebf\u56fe\uff08\u9644\u4ee3\u7801\uff09\u7684\u8be6\u7ec6\u5185\u5bb9\uff0c\u66f4\u591a\u8bf7\u5173\u6ce8\u7c73\u4e91\u5176\u5b83\u76f8\u5173\u6587\u7ae0\uff01<\/p>\n","protected":false},"excerpt":{"rendered":"<p>\u5fae\u4fe1\u5c0f\u7a0b\u5e8f\u4e2d\u5982\u4f55\u7ed8\u5236\u5929\u6c14\u6298\u7ebf\u56fe\uff1f\u4e0b\u9762\u672c\u7bc7\u6587\u7ae0\u5c31\u6765\u7ed9\u5927\u5bb6\u4ecb\u7ecd\u4e00\u4e0b\u5728\u5fae\u4fe1\u5c0f\u7a0b\u5e8f\u4e2d\u4f7f\u7528canvas\u7ed8\u5236\u5929\u6c14\u6298\u7ebf\u56fe\u7684\u65b9\u6cd5\uff0c\u4ee5\u53ca\u4f7f\u7528\u4e09\u9636\u8d1d\u585e\u5c14\u66f2\u7ebf\u62df\u5408\u6e29\u5ea6\u70b9\uff0c\u4f7f\u4e4b\u53d8\u5f97\u5706\u6ed1\uff0c\u66f2\u7ebf\u5e95\u90e8\u6709\u80cc\u666f\u8272\uff0c\u5e0c\u671b\u5bf9\u5927\u5bb6\u6709\u6240\u5e2e\u52a9\uff01 \u6298\u7ebf \u6548\u679c\u56fe\uff1a \u81ea\u5b9a\u4e49\u7ec4\u4ef6 line-chart &lt;canvas&gt;&lt;\/canvas&gt; \u767b\u5f55\u540e\u590d\u5236 Component({ &nbsp;&nbsp;externalClasses:&nbsp;[&#8216;line-class&#8217;], &nbsp;&nbsp;properties:&nbsp;{ &nbsp;&nbsp;&nbsp;&nbsp;width:&nbsp;String, &nbsp;&nbsp;&nbsp;&nbsp;height:&nbsp;String, &nbsp;&nbsp;&nbsp;&nbsp;data:&nbsp;Array, &nbsp;&nbsp;}, &nbsp;&nbsp;observers:&nbsp;{ &nbsp;&nbsp;&nbsp;&nbsp;width()&nbsp;{ &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;\/\/&nbsp;\u8fd9\u91cc\u76d1\u542c&nbsp;width&nbsp;\u53d8\u5316\u91cd\u7ed8&nbsp;canvas &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;\/\/&nbsp;\u52a8\u6001\u4f20\u5165&nbsp;width&nbsp;\u597d\u50cf\u53ea\u80fd\u8fd9\u6837\u4e86.. &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;const&nbsp;query&nbsp;=&nbsp;this.createSelectorQuery(); &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;query &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;.select(&#8216;#line&#8217;) &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;.fields({&nbsp;node:&nbsp;true,&nbsp;size:&nbsp;true&nbsp;}) &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;.exec(res&nbsp;=&amp;gt;&nbsp;{ &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;const&nbsp;canvas&nbsp;=&nbsp;res[0].node; &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;const&nbsp;ctx&nbsp;=&nbsp;canvas.getContext(&#8216;2d&#8217;); &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;const&nbsp;width&nbsp;=&nbsp;res[0].width;&nbsp;\/\/&nbsp;\u753b\u5e03\u5bbd\u5ea6 &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;const&nbsp;height&nbsp;=&nbsp;res[0].height;&nbsp;\/\/&nbsp;\u753b\u5e03\u9ad8\u5ea6 &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;console.log(`\u5bbd\u5ea6:&nbsp;${width},&nbsp;\u9ad8\u5ea6:&nbsp;${height}`); &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;const&nbsp;dpr&nbsp;=&nbsp;wx.getSystemInfoSync().pixelRatio; &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;canvas.width&nbsp;=&nbsp;width&nbsp;*&nbsp;dpr; &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;canvas.height&nbsp;=&nbsp;height&nbsp;*&nbsp;dpr; &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;ctx.scale(dpr,&nbsp;dpr); &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;\/\/&nbsp;\u5f00\u59cb\u7ed8\u56fe &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;this.drawLine(ctx,&nbsp;width,&nbsp;height,&nbsp;this.data.data); &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;}); &nbsp;&nbsp;&nbsp;&nbsp;}, &nbsp;&nbsp;}, &nbsp;&nbsp;methods:&nbsp;{ &nbsp;&nbsp;&nbsp;&nbsp;drawLine(ctx,&nbsp;width,&nbsp;height,&nbsp;data)&nbsp;{ &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;const&nbsp;Max&nbsp;=&nbsp;Math.max(&#8230;data); &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;const&nbsp;Min&nbsp;=&nbsp;Math.min(&#8230;data); &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;\/\/&nbsp;\u628a&nbsp;canvas&nbsp;\u7684\u5bbd\u5ea6,&nbsp;\u9ad8\u5ea6\u6309\u4e00\u5b9a\u89c4\u5219\u5e73\u5206 &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;const&nbsp;startX&nbsp;=&nbsp;width&nbsp;\/&nbsp;(data.length&nbsp;*&nbsp;2),&nbsp;\/\/&nbsp;\u8d77\u59cb\u70b9\u7684\u6a2a\u5750\u6807&nbsp;X &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;baseY&nbsp;=&nbsp;height&nbsp;*&nbsp;0.9,&nbsp;\/\/&nbsp;\u57fa\u7ebf\u7eb5\u5750\u6807&nbsp;Y &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;diffX&nbsp;=&nbsp;width&nbsp;\/&nbsp;data.length, &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;diffY&nbsp;=&nbsp;(height&nbsp;*&nbsp;0.7)&nbsp;\/&nbsp;(Max&nbsp;&#8211;&nbsp;Min);&nbsp;\/\/&nbsp;\u9ad8\u5ea6\u9884\u7559&nbsp;0.2&nbsp;\u5199\u6e29\u5ea6 &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;ctx.beginPath(); &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;ctx.textAlign&nbsp;=&nbsp;&#8216;center&#8217;; &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;ctx.font&nbsp;=&nbsp;&#8217;13px&nbsp;Microsoft&nbsp;YaHei&#8217;; &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;ctx.lineWidth&nbsp;=&nbsp;2; &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;ctx.strokeStyle&nbsp;=&nbsp;&#8216;#ABDCFF&#8217;; &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;\/\/&nbsp;\u753b\u6298\u7ebf\u56fe\u7684\u7ebf &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;data.forEach((item,&nbsp;index)&nbsp;=&amp;gt;&nbsp;{ &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;const&nbsp;x&nbsp;=&nbsp;startX&nbsp;+&nbsp;diffX&nbsp;*&nbsp;index, &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;y&nbsp;=&nbsp;baseY&nbsp;&#8211;&nbsp;(item&nbsp;&#8211;&nbsp;Min)&nbsp;*&nbsp;diffY; 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