{"id":4711,"date":"2020-02-04T09:41:55","date_gmt":"2020-02-04T01:41:55","guid":{"rendered":"https:\/\/www.xttblog.com\/?p=4711"},"modified":"2020-02-04T09:41:55","modified_gmt":"2020-02-04T01:41:55","slug":"%e5%89%8d%e7%ab%af%e7%bd%91%e9%a1%b5%e6%88%aa%e5%9b%be%ef%bc%9acanvas%e6%88%aa%e5%9b%be-vs-svg%e6%88%aa%e5%9b%be","status":"publish","type":"post","link":"https:\/\/www.xttblog.com\/?p=4711","title":{"rendered":"\u524d\u7aef\u7f51\u9875\u622a\u56fe\uff1aCanvas\u622a\u56fe vs SVG\u622a\u56fe"},"content":{"rendered":"\n<p class=\"wp-block-paragraph\">\u5982\u4eca\u5f88\u591a\u7f51\u7ad9\u90fd\u5f15\u5165\u622a\u56fe\u529f\u80fd\uff0c\u53ef\u7528\u4e8e\u95ee\u9898\u53cd\u9988\u3001\u5185\u5bb9\u5206\u4eab\u7b49\u5b9e\u7528\u9700\u6c42\uff0c\u800c\u524d\u7aef\u622a\u56fe\u4e5f\u4e0d\u77e5\u4e0d\u89c9\u6210\u4e3a\u4e86\u9996\u9009\u3002\u4eca\u5929\u4e3a\u5927\u5bb6\u63a8\u8350\u4e24\u79cd\u524d\u7aef\u622a\u56fe\u65b9\u5f0f\uff0c\u867d\u7136\u6709\u4e9b\u5c40\u9650\uff0c\u4f46\u662f\u4e5f\u80fd\u5e94\u4ed8\u5927\u90e8\u5206\u9879\u76ee\u9700\u6c42\u3002<br><\/p>\n\n\n\n<ul class=\"wp-block-list\"><li>Canvas\u622a\u56fe\uff1ahtml2canvas<\/li><li>SVG\u622a\u56fe\uff1arasterizehtml<\/li><\/ul>\n\n\n\n<p class=\"wp-block-paragraph\">\u539f\u7406\u5176\u5b9e\u5f88\u7b80\u5355\uff0c\u867d\u7136\u5b9e\u73b0\u65b9\u5f0f\u4e0d\u592a\u4e00\u81f4\uff0c\u4f46\u662f\u6838\u5fc3\u601d\u60f3\u662f\u76f8\u540c\u7684\u3002<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">\u4ee5html2canvas\u4e3a\u4ee3\u8868\u7684Canvas\u622a\u56fe\uff0c\u901a\u8fc7\u904d\u5386DOM\u514b\u9686\u4e00\u4efd\u526f\u672c\uff0c\u5c06\u6b64\u526f\u672c\u5728Canvas\u4e0a\u91cd\u65b0\u7ed8\u5236\uff0c\u5e76\u6839\u636eDOM\u7684\u6837\u5f0f\u5e94\u7528\u5728\u5bf9\u5e94\u7684\u7ed8\u5236\u5143\u7d20\u4e0a\uff0c\u518d\u901a\u8fc7Canvas\u751f\u6210\u56fe\u7247\u3002\u8f6c\u6362\u8fc7\u7a0b\u53ef\u7406\u89e3\u6210\uff1aDOM\u2192Canvas\u2192Image\u3002<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">\u4ee5rasterizehtml\u4e3a\u4ee3\u8868\u7684SVG\u622a\u56fe\uff0c\u901a\u8fc7\u904d\u5386DOM\u514b\u9686\u4e00\u4efd\u526f\u672c\uff0c\u5229\u7528SVG\u7684foreignObject\u628aDOM\u4f5c\u4e3a\u5916\u90e8\u8d44\u6e90\u5d4c\u5957\u5728SVG\u4e2d\uff0c\u5c06\u6b64SVG\u5728Canvas\u4e0a\u91cd\u65b0\u7ed8\u5236\uff0c\u5e76\u6839\u636eDOM\u7684\u6837\u5f0f\u5e94\u7528\u5728\u5bf9\u5e94\u7684\u7ed8\u5236\u5143\u7d20\u4e0a\uff0c\u518d\u901a\u8fc7Canvas\u751f\u6210\u56fe\u7247\u3002\u8f6c\u6362\u8fc7\u7a0b\u53ef\u7406\u89e3\u6210\uff1aDOM\u2192SVG\u7684ForeignObject\u2192Canvas\u2192Image\u3002<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">\u4e24\u79cd\u524d\u7aef\u622a\u56fe\u65b9\u5f0f\u6700\u540e\u90fd\u662f\u901a\u8fc7\u628aDOM\u7ed8\u5236\u5230Canvas\uff0c\u518d\u901a\u8fc7Canvas\u8f93\u51fa\u56fe\u7247\u3002<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">\u867d\u7136\u4e24\u79cd\u524d\u7aef\u622a\u56fe\u65b9\u5f0f\u90fd\u6709\u8fd9\u4e24\u4e2a\u5c01\u88c5\u5f97\u6bd4\u8f83\u5b8c\u5584\u7684\u7b2c\u4e09\u65b9\u5e93html2canvas\u548crasterizehtml\uff0c\u4f46\u662f\u7531\u4e8e\u5728\u8f6c\u6362\u8fc7\u7a0b\u4e2d\u5b58\u5728\u4e00\u4e9b\u81ea\u8eab\u7684\u5c40\u9650\u6027\uff0c\u6240\u4ee5\u4e5f\u5bfc\u81f4\u622a\u56fe\u53ef\u80fd\u51fa\u73b0\u4e00\u4e9b\u4e0d\u5b8c\u7f8e\u7684\u95ee\u9898\u3002<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">Canvas\u622a\u56fe\u7684\u9650\u5236\u6027\uff1a<\/p>\n\n\n\n<ul class=\"wp-block-list\"><li>\u65e0\u6cd5\u6e32\u67d3\u8de8\u57df\u8d44\u6e90(\u652f\u6301\u540c\u57df)<\/li><li>\u65e0\u6cd5\u6e32\u67d3iFrame\u548cFlash\u5185\u5bb9(\u652f\u6301SVG)<\/li><\/ul>\n\n\n\n<p class=\"wp-block-paragraph\">SVG\u622a\u56fe\u7684\u9650\u5236\u6027\uff1a<\/p>\n\n\n\n<ul class=\"wp-block-list\"><li>\u65e0\u6cd5\u6e32\u67d3\u8de8\u57df\u8d44\u6e90(\u652f\u6301\u540c\u57df)<\/li><li>\u65e0\u6cd5\u6e32\u67d3\u5982lazyload\u7b49\u901a\u8fc7JS\u52a0\u8f7d\u7684\u8d44\u6e90<\/li><li>\u65e0\u6cd5\u6e32\u67d3\u5185\u8054background-image\u6216JS\u64cd\u4f5cbackground-image<\/li><\/ul>\n\n\n\n<p class=\"wp-block-paragraph\">\u4e0d\u591a\u5e9f\u8bdd\uff0c\u76f4\u63a5\u4e0a\u4e24\u79cd\u524d\u7aef\u622a\u56fe\u65b9\u5f0f\u7684\u4ee3\u7801\uff0c\u5c0f\u4f19\u4f34\u4eec\u53ef\u6839\u636e\u9879\u76ee\u9700\u6c42\u81ea\u884c\u4f18\u5316\u4ee3\u7801\u548c\u589e\u52a0\u529f\u80fd\u54c8\u3002<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">\u6d4b\u8bd5\u4ee3\u7801\u5982\u4e0b\uff1a<\/p>\n\n\n\n<pre class=\"wp-block-code\"><code>&lt;div id=\"screenshot\"&gt;Hello World&lt;\/div&gt;\n&lt;button id=\"save-btn\"&gt;\u4fdd\u5b58&lt;\/button&gt;<\/code><\/pre>\n\n\n\n<pre class=\"wp-block-code\"><code>\/\/ \u6e32\u67d3\u56fe\u7247\nfunction Render(src, width, height, cb) {\n    const img = new Image();\n    img.src = src;\n    img.width = width;\n    img.height = height;\n    img.crossOrigin = \"\"; \/\/ \u56fe\u50cf\u8de8\u57df\u65f6\u914d\u7f6e\n    cb &amp;&amp; cb(img);\n}\n\/\/ \u4e0b\u8f7d\u56fe\u7247\nfunction Download(url, name) {\n    const target = document.createElement(\"a\");\n    target.href = url;\n    target.download = name;\n    const event = document.createEvent(\"MouseEvents\");\n    event.initEvent(\"click\", true, true);\n    target.dispatchEvent(event);\n}<\/code><\/pre>\n\n\n\n<p class=\"wp-block-paragraph\">Canvas\u622a\u56fe\u6838\u5fc3\u4ee3\u7801\u5982\u4e0b\u6240\u793a\uff1a<\/p>\n\n\n\n<pre class=\"wp-block-code\"><code>import Html2canvas from \"html2canvas\";\nconst btn = document.getElementById(\"save-btn\");\nbtn.addEventListener(\"click\", () =&gt; {\n    const screenshot = document.getElementById(\"screenshot\");\n    \/\/ allowTaint: true, \/\/ \u4e0d\u80fd\u4e0euseCORS\u5171\u7528\n    const opts = {\n        logging: false,\n        scale: 2,\n        useCORS: true\n    };\n    Html2canvas(screenshot, opts).then(res =&gt; {\n        const { height, width } = res;\n        const base64 = res.toDataURL(\"image\/png\", 1);\n        Render(base64, width, height, img =&gt; {\n            document.body.appendChild(img);\n            Download(base64, \"screenshot.png\");\n        });\n    }, err =&gt; alert(\"\u622a\u56fe\u5931\u8d25\uff0c\u8bf7\u91cd\u65b0\u5c1d\u8bd5\"));\n});<\/code><\/pre>\n\n\n\n<p class=\"wp-block-paragraph\">SVG\u622a\u56fe\u6838\u5fc3\u4ee3\u7801\u5982\u4e0b\u6240\u793a\uff1a<\/p>\n\n\n\n<pre class=\"wp-block-code\"><code>import Rasterizehtml from \"rasterizehtml\";\nconst btn = document.getElementById(\"save-btn\");\nbtn.addEventListener(\"click\", () =&gt; {\n    \/\/ drawURL()\u52a0\u8f7d\u7684URL\u5fc5\u987b\u662f\u540c\u57df\u540dURL\u6216\u652f\u6301\u8de8\u57df\u7684URL\n    \/\/ \u4e0b\u9762\u7684URL\u662f\u968f\u4fbf\u5199\u7684\uff0c\u8bb0\u5f97\u6362\u6210\u540c\u57df\u540dURL\u6216\u652f\u6301\u8de8\u57df\u7684URL\n    const url = \"https:\/\/www.baidu.com\";\n    const canvas = document.createElement(\"canvas\");\n    const opts = {\n        executeJs: true,\n        height: screen.height,\n        width: screen.width\n    };\n    Rasterizehtml.drawURL(url, canvas, opts).then(res =&gt; {\n        const base64 = \"data:image\/svg+xml;base64,\" + btoa(unescape(encodeURIComponent(res.svg)));\n        Render(base64, opts.width, opts.height, img =&gt; {\n            document.body.appendChild(img);\n            Download(base64, \"screenshot.png\");\n        });\n    }, err =&gt; alert(\"\u622a\u56fe\u5931\u8d25\uff0c\u8bf7\u91cd\u65b0\u5c1d\u8bd5\"));\n});<\/code><\/pre>\n\n\n\n<p class=\"wp-block-paragraph\">\u53e6\u5916\u8fd8\u6709\u51e0\u70b9\u9700\u8981\u6ce8\u610f\u4e00\u4e0b\uff1a<\/p>\n\n\n\n<ul class=\"wp-block-list\"><li>\u4f7f\u7528Canvas\u622a\u56fe\u517c\u5bb9\u4f4e\u7248\u672c\u6d4f\u89c8\u5668\u65f6\uff0c\u4e0d\u80fd\u4f7f\u7528CSS3\u5c5e\u6027\u548c\u5e26\u6709\u524d\u7f00\u7684\u5c5e\u6027<\/li><li>\u4f7f\u7528SVG\u622a\u56fe\u53ef\u83b7\u53d6\u540c\u57df&lt; iframe&gt;\u5185\u5bb9\u8fdb\u884c\u6e32\u67d3<\/li><li>\u4f7f\u7528SVG\u622a\u56fe\u53ef\u83b7\u53d6\u540c\u57df<\/li><\/ul>\n\n\n\n<p class=\"wp-block-paragraph\">\u611f\u5174\u8da3\u7684\u7f51\u53cb\u53ef\u7ed3\u5408\u81ea\u8eab\u9879\u76ee\u5c1d\u8bd5\u4e00\u4e0b\u4e24\u79cd\u524d\u7aef\u622a\u56fe\u65b9\u5f0f\uff0c\u63a2\u7a76\u4e0b\u5176\u76f8\u540c\u70b9\u548c\u4e0d\u540c\u70b9\u3002\u5982\u679c\u5bf9\u5176\u622a\u56fe\u539f\u7406\u611f\u5174\u8da3\uff0c\u53ef\u5256\u6790\u4e0bhtml2canvas\u548crasterizehtml\u7684\u6e90\u7801\uff0c\u76f8\u4fe1\u4f60\u4f1a\u6709\u610f\u5916\u7684\u6536\u83b7\u5594\uff01<\/p>\n<!-- <audio autoplay=\"autoplay\" height=\"100\" width=\"100\" hidden=\"true\"><source src=\"https:\/\/c.coka.la\/orAvPR.mp3\" type=\"audio\/mp3\"\/><\/audio><img decoding=\"async\" src=\"https:\/\/images.weserv.nl\/?url=https:\/\/ws3.sinaimg.cn\/large\/8fa5dcfcgy1g4em3rzar5j20ib089ae0.jpg\" alt=\"\u4e1a\u4f59\u8349\u516c\u4f17\u53f7\"\/> --><p><!-- <img decoding=\"async\" src=\"https:\/\/raw.githubusercontent.com\/xmt1139057136\/xttblog\/master\/8fa5dcfcgy1g4em3rzar5j20ib089ae0.jpg\" alt=\"\u4e1a\u4f59\u8349\u516c\u4f17\u53f7\"\/>--><img decoding=\"async\" src=\"https:\/\/saas.51autoparts.cn\/api\/admin\/sys-file\/oss\/file?fileName=84db51f8561e448f9a4fda2eff0811f9.jpg\" alt=\"\u4e1a\u4f59\u8349\u516c\u4f17\u53f7\"\/><\/p><p>\u6700\u540e\uff0c\u6b22\u8fce\u5173\u6ce8\u6211\u7684\u4e2a\u4eba\u5fae\u4fe1\u516c\u4f17\u53f7\uff1a\u4e1a\u4f59\u8349\uff08yyucao\uff09\uff01<b>\u53ef\u52a0\u4f5c\u8005\u5fae\u4fe1\u53f7\uff1a<font color=\"red\">xttblog2<\/font>\u3002\u5907\u6ce8\uff1a\u201c1\u201d\uff0c\u6dfb\u52a0\u535a\u4e3b\u5fae\u4fe1\u62c9\u4f60\u8fdb\u5fae\u4fe1\u7fa4\u3002\u5907\u6ce8\u9519\u8bef\u4e0d\u4f1a\u540c\u610f\u597d\u53cb\u7533\u8bf7\u3002<\/b>\u518d\u6b21\u611f\u8c22\u60a8\u7684\u5173\u6ce8\uff01\u540e\u7eed\u6709\u7cbe\u5f69\u5185\u5bb9\u4f1a\u7b2c\u4e00\u65f6\u95f4\u53d1\u7ed9\u60a8\uff01\u539f\u521b\u6587\u7ae0\u6295\u7a3f\u8bf7\u53d1\u9001\u81f3532009913@qq.com\u90ae\u7bb1\u3002\u5546\u52a1\u5408\u4f5c\u4e5f\u53ef\u6dfb\u52a0\u4f5c\u8005\u5fae\u4fe1\u8fdb\u884c\u8054\u7cfb\uff01<\/p><p>\u672c\u6587\u539f\u6587\u51fa\u5904\uff1a<a href=\"https:\/\/www.xttblog.com\">\u4e1a\u4f59\u8349<\/a>\uff1a &raquo; <a href=\"https:\/\/www.xttblog.com\/?p=4711\">\u524d\u7aef\u7f51\u9875\u622a\u56fe\uff1aCanvas\u622a\u56fe vs SVG\u622a\u56fe<\/a><\/p><!-- <div class=\"bd-reward-stl\"><button id=\"bdRewardBtn\"><span><\/span><\/button><\/div> -->","protected":false},"excerpt":{"rendered":"<p>\u5982\u4eca\u5f88\u591a\u7f51\u7ad9\u90fd\u5f15\u5165\u622a\u56fe\u529f\u80fd\uff0c\u53ef\u7528\u4e8e\u95ee\u9898\u53cd\u9988\u3001\u5185\u5bb9\u5206\u4eab\u7b49\u5b9e\u7528\u9700\u6c42\uff0c\u800c\u524d\u7aef\u622a\u56fe\u4e5f\u4e0d\u77e5\u4e0d\u89c9\u6210\u4e3a\u4e86\u9996\u9009\u3002\u4eca\u5929\u4e3a\u5927\u5bb6\u63a8\u8350 [&hellip;]<\/p>\n","protected":false},"author":2,"featured_media":0,"comment_status":"closed","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[4],"tags":[31,54,1559,2066,52],"class_list":["post-4711","post","type-post","status-publish","format-standard","hentry","category-html5","tag-canvas","tag-html2canvas","tag-iframe","tag-rasterizehtml","tag-svg"],"_links":{"self":[{"href":"https:\/\/www.xttblog.com\/index.php?rest_route=\/wp\/v2\/posts\/4711","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.xttblog.com\/index.php?rest_route=\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.xttblog.com\/index.php?rest_route=\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.xttblog.com\/index.php?rest_route=\/wp\/v2\/users\/2"}],"replies":[{"embeddable":true,"href":"https:\/\/www.xttblog.com\/index.php?rest_route=%2Fwp%2Fv2%2Fcomments&post=4711"}],"version-history":[{"count":1,"href":"https:\/\/www.xttblog.com\/index.php?rest_route=\/wp\/v2\/posts\/4711\/revisions"}],"predecessor-version":[{"id":4712,"href":"https:\/\/www.xttblog.com\/index.php?rest_route=\/wp\/v2\/posts\/4711\/revisions\/4712"}],"wp:attachment":[{"href":"https:\/\/www.xttblog.com\/index.php?rest_route=%2Fwp%2Fv2%2Fmedia&parent=4711"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.xttblog.com\/index.php?rest_route=%2Fwp%2Fv2%2Fcategories&post=4711"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.xttblog.com\/index.php?rest_route=%2Fwp%2Fv2%2Ftags&post=4711"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}