---
title: CanvasRenderingContext2D.fillText()
slug: Web/API/CanvasRenderingContext2D/fillText
translation_of: Web/API/CanvasRenderingContext2D/fillText
---
<div>{{APIRef}}</div>

<p><code><strong>CanvasRenderingContext2D</strong></code><strong><code>.fillText()</code></strong> 是 Canvas 2D API 在 <em>(x, y)</em>位置填充文本的方法。如果选项的第四个参数提供了最大宽度，文本会进行缩放以适应最大宽度。</p>

<p>参见 {{domxref("CanvasRenderingContext2D.strokeText()")}} 方法对文本进行描边。</p>

<h2 id="语法">语法</h2>

<pre class="syntaxbox notranslate">void <var><em>ctx</em>.fillText(text, x, y, [maxWidth]);</var>
</pre>

<h3 id="参数">参数</h3>

<dl>
 <dt><code>text</code></dt>
 <dd>使用当前的 {{domxref("CanvasRenderingContext2D.font","font")}}, {{domxref("CanvasRenderingContext2D.textAlign","textAlign")}}, {{domxref("CanvasRenderingContext2D.textBaseline","textBaseline")}} 和 {{domxref("CanvasRenderingContext2D.direction","direction")}} 值对文本进行渲染。</dd>
</dl>

<dl>
 <dt><code>x</code></dt>
 <dd>文本起点的 x 轴坐标。</dd>
 <dt><code>y</code></dt>
 <dd>文本起点的 y 轴坐标。</dd>
 <dt><code>maxWidth</code> {{optional_inline}}</dt>
 <dd>绘制的最大宽度。如果指定了值，并且经过计算字符串的值比最大宽度还要宽，字体为了适应会水平缩放（如果通过水平缩放当前字体，可以进行有效的或者合理可读的处理）或者使用小号的字体。</dd>
</dl>

<h2 id="示例">示例</h2>

<h3 id="使用_fillText_方法">使用 <code>fillText</code> 方法</h3>

<p>这是一段使用 <code>fillText</code> 方法的简单的代码片段。</p>

<h4 id="HTML">HTML</h4>

<pre class="brush: html notranslate">&lt;canvas id="canvas"&gt;&lt;/canvas&gt;
</pre>

<h4 id="JavaScript">JavaScript</h4>

<pre class="brush: js; highlight:[5] notranslate">var canvas = document.getElementById("canvas");
var ctx = canvas.getContext("2d");

ctx.font = "48px serif";
ctx.fillText("Hello world", 50, 100);
</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 notranslate">&lt;canvas id="canvas" width="400" height="200" class="playable-canvas"&gt;&lt;/canvas&gt;
&lt;div class="playable-buttons"&gt;
  &lt;input id="edit" type="button" value="Edit" /&gt;
  &lt;input id="reset" type="button" value="Reset" /&gt;
&lt;/div&gt;
&lt;textarea id="code" class="playable-code"&gt;
ctx.font = "48px serif";
ctx.fillText("Hello world", 50, 100);&lt;/textarea&gt;
</pre>

<pre class="brush: js notranslate">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="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-filltext", "CanvasRenderingContext2D.fillText")}}</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>{{ CompatGeckoDesktop("1.9.1") }}</td>
   <td>{{ CompatIE(9) }}</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>{{ CompatGeckoMobile("1.9.1") }}</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.strokeText()")}}</li>
</ul>