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diff --git a/files/zh-cn/web/api/canvasrenderingcontext2d/textbaseline/index.html b/files/zh-cn/web/api/canvasrenderingcontext2d/textbaseline/index.html new file mode 100644 index 0000000000..d5b7f3a5c6 --- /dev/null +++ b/files/zh-cn/web/api/canvasrenderingcontext2d/textbaseline/index.html @@ -0,0 +1,130 @@ +--- +title: CanvasRenderingContext2D.textBaseline +slug: Web/API/CanvasRenderingContext2D/textBaseline +tags: + - Canvas + - CanvasRenderingContext2D +translation_of: Web/API/CanvasRenderingContext2D/textBaseline +--- +<div>{{APIRef}}</div> + +<p><code><strong>CanvasRenderingContext2D</strong></code><strong><code>.textBaseline</code></strong> 是 Canvas 2D API 描述绘制文本时,当前文本基线的属性。</p> + +<blockquote> +<p>译者注:决定文字垂直方向的对齐方式。</p> +</blockquote> + +<h2 id="语法">语法</h2> + +<pre class="syntaxbox"><var><em>ctx</em>.textBaseline = "top" || "hanging" || "middle" || "alphabetic" || "ideographic" || "bottom";</var> +</pre> + +<h3 id="选项">选项</h3> + +<p>有效值:</p> + +<dl> + <dt>top</dt> + <dd>文本基线在文本块的顶部。</dd> + <dt>hanging</dt> + <dd>文本基线是悬挂基线。</dd> + <dt>middle</dt> + <dd>文本基线在文本块的中间。</dd> + <dt>alphabetic</dt> + <dd>文本基线是标准的字母基线。</dd> + <dt>ideographic</dt> + <dd>文字基线是表意字基线;如果字符本身超出了alphabetic 基线,那么ideograhpic基线位置在字符本身的底部。</dd> + <dt>bottom</dt> + <dd>文本基线在文本块的底部。 与 ideographic 基线的区别在于 ideographic 基线不需要考虑下行字母。</dd> +</dl> + +<p>默认值是 <code>alphabetic。</code></p> + +<h2 id="示例">示例</h2> + +<h3 id="Using_the_textBaseline_property" name="Using_the_textBaseline_property">使用 <code>textBaseline</code> 属性</h3> + +<p>这是一段简单的代码片段,使用 <code>textBaseline</code> 属性设置不同的文本基线。</p> + +<h4 id="HTML">HTML</h4> + +<pre class="brush: html"><canvas id="canvas" width="550" height="500"></canvas></pre> + +<h4 id="JavaScript">JavaScript</h4> + +<pre class="brush: js">const canvas = document.getElementById('canvas'); +const ctx = canvas.getContext('2d'); + +const baselines = ['top', 'hanging', 'middle', 'alphabetic', 'ideographic', 'bottom']; +ctx.font = '36px serif'; +ctx.strokeStyle = 'red'; + +baselines.forEach(function (baseline, index) { + ctx.textBaseline = baseline; + let y = 75 + index * 75; + ctx.beginPath(); + ctx.moveTo(0, y + 0.5); + ctx.lineTo(550, y + 0.5); + ctx.stroke(); + ctx.fillText('Abcdefghijklmnop (' + baseline + ')', 0, y); +});</pre> + + + +<div class="hidden"> +<h6 id="Playable_code" name="Playable_code">Playable code</h6> + +<pre class="brush: html"><canvas id="canvas" width="550" height="500"></canvas></pre> + +<pre class="brush: js">const canvas = document.getElementById('canvas'); +const ctx = canvas.getContext('2d'); + +const baselines = ['top', 'hanging', 'middle', 'alphabetic', 'ideographic', 'bottom']; +ctx.font = '36px serif'; +ctx.strokeStyle = 'red'; + +baselines.forEach(function (baseline, index) { + ctx.textBaseline = baseline; + let y = 75 + index * 75; + ctx.beginPath(); + ctx.moveTo(0, y + 0.5); + ctx.lineTo(550, y + 0.5); + ctx.stroke(); + ctx.fillText('Abcdefghijklmnop (' + baseline + ')', 0, y); +});</pre> +</div> + +<h4 id="结果">结果</h4> + +<p>{{ EmbedLiveSample('Playable_code', 700, 550) }}</p> + +<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-textbaseline", "CanvasRenderingContext2D.textBaseline")}}</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.textBaseline")}}</p> + +<h2 id="参见">参见</h2> + +<ul> + <li>接口定义,{{domxref("CanvasRenderingContext2D")}}.</li> +</ul> |
