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diff --git a/files/zh-cn/web/api/canvasrenderingcontext2d/font/index.html b/files/zh-cn/web/api/canvasrenderingcontext2d/font/index.html new file mode 100644 index 0000000000..963c27c32e --- /dev/null +++ b/files/zh-cn/web/api/canvasrenderingcontext2d/font/index.html @@ -0,0 +1,141 @@ +--- +title: CanvasRenderingContext2D.font +slug: Web/API/CanvasRenderingContext2D/font +tags: + - API + - Canvas + - CanvasRenderingContext2D +translation_of: Web/API/CanvasRenderingContext2D/font +--- +<div>{{APIRef}}</div> + +<p><code><strong>CanvasRenderingContext2D</strong></code><strong><code>.font</code></strong> 是 Canvas 2D API 描述绘制文字时,当前字体样式的属性。 使用和 <a href="/en-US/docs/Web/CSS/font" title="en/CSS/font">CSS font</a> 规范相同的字符串值。</p> + +<h2 id="语法">语法</h2> + +<pre class="syntaxbox"><var><em>ctx</em>.font = value;</var> +</pre> + +<h3 id="选项">选项</h3> + +<dl> + <dt><code>value</code></dt> + <dd>符合CSS {{cssxref("font")}} 语法的{{domxref("DOMString")}} 字符串。默认字体是 10px sans-serif。</dd> +</dl> + +<h2 id="示例">示例</h2> + +<h3 id="使用自定义字体" name="使用自定义字体">使用自定义字体</h3> + +<p>这个例子使用 <code>font</code> 属性设置了不同的字体大小和字体种类。</p> + +<h4 id="HTML">HTML</h4> + +<pre class="brush: html"><canvas id="canvas"></canvas> +</pre> + +<h4 id="JavaScript">JavaScript</h4> + +<pre class="brush: js">var canvas = document.getElementById("canvas"); +var ctx = canvas.getContext("2d"); + +ctx.font = "bold 48px serif"; +ctx.strokeText("Hello world", 50, 100); +</pre> + +<h4 id="结果">结果</h4> + +<div class="hidden"> +<h2 id="Playable_code">Playable_code</h2> + +<h3 id="HTML_2">HTML</h3> + +<pre class="brush: html"><canvas id="canvas" width="400" height="200" class="playable-canvas"></canvas> +<div class="playable-buttons"> + <input id="edit" type="button" value="编辑" /> + <input id="reset" type="button" value="重置" /> +</div> +<textarea id="code" class="playable-code"> +ctx.font = "bold 48px serif"; +ctx.strokeText("Hello world", 50, 100);</textarea> +</pre> + +<h3 id="JavaScript_2">JavaScript</h3> + +<pre class="brush: js">var canvas = document.getElementById("canvas"); +var ctx = canvas.getContext("2d"); +var textarea = document.getElementById("code"); +var reset = document.getElementById("reset"); +var edit = document.getElementById("edit"); +var code = textarea.value; + +function drawCanvas() { + ctx.clearRect(0, 0, canvas.width, canvas.height); + eval(textarea.value); +} + +reset.addEventListener("click", function() { + textarea.value = code; + drawCanvas(); +}); + +edit.addEventListener("click", function() { + textarea.focus(); +}) + +textarea.addEventListener("input", drawCanvas); +window.addEventListener("load", drawCanvas); +</pre> +</div> + +<p>{{EmbedLiveSample('Playable_code', 700, 360)}}</p> + +<h2 id="sect1"></h2> + +<h3 id="使用CSS字体加载API加载字体">使用CSS字体加载API加载字体</h3> + +<p>借助{{domxref("FontFace")}} API的帮助,您可以在画布中使用字体之前显式加载字体。</p> + +<pre>let f = new FontFace('test', 'url(x)'); + +f.load().then(function() { + // Ready to use the font in a canvas context +});</pre> + +<h2 id="规范描述">规范描述</h2> + +<table class="standard-table"> + <tbody> + <tr> + <th scope="col">Specification</th> + <th scope="col">Status</th> + <th scope="col">Comment</th> + </tr> + <tr> + <td>{{SpecName('HTML WHATWG', "scripting.html#dom-context-2d-font", "CanvasRenderingContext2D.font")}}</td> + <td>{{Spec2('HTML WHATWG')}}</td> + <td></td> + </tr> + </tbody> +</table> + +<h2 id="浏览器兼容性">浏览器兼容性</h2> + +<div class="hidden"> +<p>此页面上的兼容性表是根据结构化数据生成的。 如果您想提供数据,请查看<a href="https://github.com/mdn/browser-compat-data">https://github.com/mdn/browser-compat-data</a>并向我们发送请求请求。</p> +</div> + +<p>{{Compat("api.CanvasRenderingContext2D.font")}}</p> + +<h3 id="Gecko-specific_注解">Gecko-specific 注解</h3> + +<ul> + <li>基于Gecko的浏览器, 例如 Firefox, 实现了一个非标准的并且不赞成使用的属性 <code>ctx.mozTextStyle</code> 。不要使用此属性。</li> + <li>在Gecko中,当将系统字体设置为canvas 2D上下文的{{domxref("CanvasRenderingContext2D.font", "font")}}(例如菜单)的值时,获取用于无法返回期望字体的字体值 (不返回任何内容)。 这已在Firefox 57({{bug(1374885)}})中发布的Firefox的<a href="https://wiki.mozilla.org/Quantum/Stylo">Quantum/Stylo</a>并行CSS引擎中修复。</li> +</ul> + +<h2 id="参见">参见</h2> + +<ul> + <li>接口定义,{{domxref("CanvasRenderingContext2D")}}</li> +</ul> |