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---
title: CanvasRenderingContext2D.setLineDash()
slug: Web/API/CanvasRenderingContext2D/setLineDash
translation_of: Web/API/CanvasRenderingContext2D/setLineDash
---
<div>{{APIRef}}</div>
<p>The <code><strong>CanvasRenderingContext2D</strong></code><strong><code>.setLineDash()</code></strong> method of the Canvas 2D API sets the line dash pattern.</p>
<h2 id="Syntax">Syntax</h2>
<pre class="syntaxbox">void <var><em>ctx</em>.setLineDash(segments);</var>
</pre>
<h3 id="Parameters">Parameters</h3>
<dl>
<dt><code>segments</code></dt>
<dd>An {{jsxref("Array")}}. A list of numbers that specifies distances to alternately draw a line and a gap (in coordinate space units). If the number of elements in the array is odd, the elements of the array get copied and concatenated. For example, <code>[5, 15, 25]</code> will become <code>[5, 15, 25, 5, 15, 25]</code>. An empty array clears the dashes, so that a solid line will be drawn.</dd>
</dl>
<h2 id="Examples">Examples</h2>
<h3 id="Using_the_setLineDash_method">Using the <code>setLineDash</code> method</h3>
<p>This is just a simple code snippet which uses the <code>setLineDash</code> method to draw a dashed line.</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:[4]">var canvas = document.getElementById("canvas");
var ctx = canvas.getContext("2d");
ctx.setLineDash([5, 15]);
ctx.beginPath();
ctx.moveTo(0,100);
ctx.lineTo(400, 100);
ctx.stroke();
</pre>
<p>Edit the code below and see your changes update live in the canvas:</p>
<div class="hidden">
<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">
ctx.setLineDash([5, 15]);
ctx.beginPath();
ctx.moveTo(0,100);
ctx.lineTo(400, 100);
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, 360) }}</p>
<h2 id="Specifications">Specifications</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-setlinedash", "CanvasRenderingContext2D.setLineDash")}}</td>
<td>{{Spec2('HTML WHATWG')}}</td>
<td> </td>
</tr>
</tbody>
</table>
<h2 id="Browser_compatibility">Browser compatibility</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(27) }}</td>
<td>{{ CompatIE(11) }}</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(27) }}</td>
<td>{{CompatVersionUnknown}}</td>
<td>{{CompatVersionUnknown}}</td>
<td>{{CompatVersionUnknown}}</td>
</tr>
</tbody>
</table>
</div>
<h2 id="Gecko-specific_notes">Gecko-specific notes</h2>
<ul>
<li>Starting with Gecko 7.0 {{geckoRelease("7.0")}}, the non-standard and deprecated property <code>mozDash</code> has been implemented to set and get a dash list. This property will be deprecated and removed in the future, see {{bug(931643)}}. Use <code>setLineDash()</code> instead.</li>
</ul>
<h2 id="WebKit-specific_notes">WebKit-specific notes</h2>
<ul>
<li>In WebKit-based browsers (e.g. Safari), the non-standard and deprecated property <code>webkitLineDash</code> is implemented besides this method. Use <code>setLineDash()</code> instead.</li>
</ul>
<h2 id="See_also">See also</h2>
<ul>
<li>The interface defining it, {{domxref("CanvasRenderingContext2D")}}</li>
<li>{{domxref("CanvasRenderingContext2D.getLineDash()")}}</li>
<li>{{domxref("CanvasRenderingContext2D.lineDashOffset")}}</li>
</ul>
|
