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diff --git a/files/zh-cn/web/api/canvasrenderingcontext2d/closepath/index.html b/files/zh-cn/web/api/canvasrenderingcontext2d/closepath/index.html new file mode 100644 index 0000000000..8446adbac8 --- /dev/null +++ b/files/zh-cn/web/api/canvasrenderingcontext2d/closepath/index.html @@ -0,0 +1,160 @@ +--- +title: CanvasRenderingContext2D.closePath() +slug: Web/API/CanvasRenderingContext2D/closePath +translation_of: Web/API/CanvasRenderingContext2D/closePath +--- +<div>{{APIRef}}</div> + +<p><code><strong>CanvasRenderingContext2D</strong></code><strong><code>.closePath()</code></strong> 是 Canvas 2D API 将笔点返回到当前子路径起始点的方法。它尝试从当前点到起始点绘制一条直线。 如果图形已经是封闭的或者只有一个点，那么此方法不会做任何操作。</p> + +<h2 id="语法">语法</h2> + +<pre class="syntaxbox">void <var><em>ctx</em>.closePath();</var> +</pre> + +<h2 id="示例">示例</h2> + +<h3 id="使用_closePath_方法">使用 <code>closePath</code> 方法</h3> + +<p>这是一段使用 <code>closePath</code> 方法的简单的代码片段。</p> + +<h4 id="HTML">HTML</h4> + +<pre class="brush: html"><canvas id="canvas"></canvas> +</pre> + +<h4 id="JavaScript">JavaScript</h4> + +<pre class="brush: js; highlight:[8]">var canvas = document.getElementById("canvas"); +var ctx = canvas.getContext("2d"); + +ctx.beginPath(); +ctx.moveTo(20,20); +ctx.lineTo(200,20); +ctx.lineTo(120,120); +ctx.closePath(); // draws last line of the triangle +ctx.stroke(); +</pre> + +<p>修改下面的代码并在线查看 canvas 的变化：</p> + +<div style="display: none;"> +<h6 id="Playable_code">Playable code</h6> + +<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="Edit" /> + <input id="reset" type="button" value="Reset" /> +</div> +<textarea id="code" class="playable-code" style="height:140px;"> +ctx.beginPath(); +ctx.moveTo(20,20); +ctx.lineTo(200,20); +ctx.lineTo(120,120); +ctx.closePath(); // draws last line of the triangle +ctx.stroke();</textarea> +</pre> + +<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, 400) }}</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-closepath", "CanvasRenderingContext2D.closePath")}}</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> + +<p>{{CompatibilityTable}}</p> + +<div id="compat-desktop"> +<table class="compat-table"> + <tbody> + <tr> + <th>Feature</th> + <th>Chrome</th> + <th>Firefox (Gecko)</th> + <th>Internet Explorer</th> + <th>Opera</th> + <th>Safari</th> + </tr> + <tr> + <td>Basic support</td> + <td>{{CompatVersionUnknown}}</td> + <td>{{CompatVersionUnknown}}</td> + <td>{{CompatVersionUnknown}}</td> + <td>{{CompatVersionUnknown}}</td> + <td>{{CompatVersionUnknown}}</td> + </tr> + </tbody> +</table> +</div> + +<div id="compat-mobile"> +<table class="compat-table"> + <tbody> + <tr> + <th>Feature</th> + <th>Android</th> + <th>Chrome for Android</th> + <th>Firefox Mobile (Gecko)</th> + <th>IE Mobile</th> + <th>Opera Mobile</th> + <th>Safari Mobile</th> + </tr> + <tr> + <td>Basic support</td> + <td>{{CompatVersionUnknown}}</td> + <td>{{CompatVersionUnknown}}</td> + <td>{{CompatVersionUnknown}}</td> + <td>{{CompatVersionUnknown}}</td> + <td>{{CompatVersionUnknown}}</td> + <td>{{CompatVersionUnknown}}</td> + </tr> + </tbody> +</table> +</div> + +<h2 id="参见">参见</h2> + +<ul> + <li>接口定义， {{domxref("CanvasRenderingContext2D")}}</li> + <li>{{domxref("CanvasRenderingContext2D.beginPath()")}}</li> +</ul> |