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+---
+title: CanvasRenderingContext2D.clearRect()
+slug: Web/API/CanvasRenderingContext2D/clearRect
+tags:
+  - API
+  - Canvas
+  - CanvasRenderingContext2D
+  - Referencia
+  - metodo
+translation_of: Web/API/CanvasRenderingContext2D/clearRect
+---
+<div>{{APIRef}}</div>
+
+<p>O método <code><strong>CanvasRenderingContext2D</strong></code><strong><code>.clearRect()</code></strong> da API Canvas 2D limpa todos os pixels de um retângulo definido na posição <em>(x, y)</em> e tamanho (<em>width</em> (largura)<em>, height </em>(altura)) para uma cor preta transparente, apagando algum conteúdo anterior.</p>
+
+<h2 id="Sintaxe">Sintaxe</h2>
+
+<pre class="syntaxbox">void <var><em>ctx</em>.clearRect(x, y, width, height);</var>
+</pre>
+
+<h3 id="Parâmetros">Parâmetros</h3>
+
+<dl>
+ <dt><code>x</code></dt>
+ <dd>O valor da coordenada x para o ponto inicial do retângulo.</dd>
+ <dt><code>y</code></dt>
+ <dd>O valor da coordenada y para o ponto inicial do retângulo.</dd>
+ <dt><code>width</code></dt>
+ <dd>A largura do retângulo.</dd>
+ <dt><code>height</code></dt>
+ <dd>A altura do retângulo.</dd>
+</dl>
+
+<h2 id="Notas_de_uso">Notas de uso</h2>
+
+<p>Um problema comum com <code>clearRect</code> que pode acontecer, é que pode não funcionar corretamente, caso não seja usada alguma <a href="https://developer.mozilla.org/pt_BR/docs/Web/API/Canvas_API/Tutorial/Drawing_shapes#Drawing_paths">propriedade de <em>path</em></a>. Não esqueça de usar {{domxref("CanvasRenderingContext2D.beginPath", "beginPath()")}} antes de começar um novo frame depois de chamar <code>clearRect</code>.</p>
+
+<h2 id="Exemplos">Exemplos</h2>
+
+<h3 id="Usando_o_método_clearRect">Usando o método <code>clearRect</code></h3>
+
+<p>Isto é só um simples trecho de código que usa o método <code>clearRect</code>.</p>
+
+<h4 id="HTML">HTML</h4>
+
+<pre class="brush: html">&lt;canvas id="canvas"&gt;&lt;/canvas&gt;
+</pre>
+
+<h4 id="JavaScript">JavaScript</h4>
+
+<pre class="brush: js; highlight:[11]">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();
+
+ctx.clearRect(10, 10, 100, 100);
+
+// clear the whole canvas
+// ctx.clearRect(0, 0, canvas.width, canvas.height);
+</pre>
+
+<p>Edite o código abaixo e veja as alterações instantâneas no canvas:</p>
+
+<div style="display: none;">
+<h6 id="Playable_code">Playable code</h6>
+
+<pre class="brush: html">&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" style="height:140px;"&gt;
+ctx.beginPath();
+ctx.moveTo(20,20);
+ctx.lineTo(200,20);
+ctx.lineTo(120,120);
+ctx.closePath(); // draws last line of the triangle
+ctx.stroke();
+
+ctx.clearRect(10, 10, 100, 100);&lt;/textarea&gt;
+</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="Especificações">Especificações</h2>
+
+<table class="standard-table">
+ <tbody>
+  <tr>
+   <th scope="col">Especificação</th>
+   <th scope="col">Estado</th>
+   <th scope="col">Comentário</th>
+  </tr>
+  <tr>
+   <td>{{SpecName('HTML WHATWG', "scripting.html#dom-context-2d-clearrect", "CanvasRenderingContext2D.clearRect")}}</td>
+   <td>{{Spec2('HTML WHATWG')}}</td>
+   <td> </td>
+  </tr>
+ </tbody>
+</table>
+
+<h2 id="Compatibilidade_em_Navegadores">Compatibilidade em Navegadores</h2>
+
+<p>{{CompatibilityTable}}</p>
+
+<div id="compat-desktop">
+<table class="compat-table">
+ <tbody>
+  <tr>
+   <th>Característica</th>
+   <th>Chrome</th>
+   <th>Edge</th>
+   <th>Firefox (Gecko)</th>
+   <th>Internet Explorer</th>
+   <th>Opera</th>
+   <th>Safari</th>
+  </tr>
+  <tr>
+   <td>Suporte básico</td>
+   <td>{{CompatVersionUnknown}}</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>Característica</th>
+   <th>Android</th>
+   <th>Chrome para Android</th>
+   <th>Edge</th>
+   <th>Firefox Mobile (Gecko)</th>
+   <th>IE Mobile</th>
+   <th>Opera Mobile</th>
+   <th>Safari Mobile</th>
+  </tr>
+  <tr>
+   <td>Suporte básico</td>
+   <td>{{CompatVersionUnknown}}</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="Veja_também">Veja também</h2>
+
+<ul>
+ <li>A definição da interface {{domxref("CanvasRenderingContext2D")}}</li>
+ <li>{{domxref("CanvasRenderingContext2D.fillRect()")}}</li>
+ <li>{{domxref("CanvasRenderingContext2D.strokeRect()")}}</li>
+</ul>