[英]Set Canvas size using javascript
我在html中有以下代碼:
<canvas id="myCanvas" width =800 height=800>
我不想將width
指定為800
,而是調用 JavaScript 函數getWidth()
來獲取寬度,例如
<canvas id="myCanvas" width =getWidth() height=800>
正確的語法是什么? 因為我正在做的事情不起作用。
您可以像這樣設置寬度:
function draw() {
var ctx = (a canvas context);
ctx.canvas.width = window.innerWidth;
ctx.canvas.height = window.innerHeight;
//...drawing code...
}
function setWidth(width) {
var canvas = document.getElementById("myCanvas");
canvas.width = width;
}
嘗試這個:
var setCanvasSize = function() {
canvas.width = window.innerWidth;
canvas.height = window.innerHeight;
}
要設置畫布的寬度和高度,您可以使用畫布的寬度和高度對象屬性來設置寬度和高度。
HTML - 代碼
<canvas id="canvas"></canvas>
Javascript
const canvas = document.getElementById('canvas')
canvas.width = 300 // 300px
canvas.height = 200 //200px
const canvas = document.getElementById('canvas') canvas.width = 350 canvas.height = 200
#canvas { background-color:blue }
<canvas id="canvas"></canvas>
嘗試這個:
var w = window,
d = document,
e = d.documentElement,
g = d.getElementsByTagName('body')[0],
xS = w.innerWidth || e.clientWidth || g.clientWidth,
yS = w.innerHeight|| e.clientHeight|| g.clientHeight;
alert(xS + ' × ' + yS);
document.write('')
適用於 iframe 並且很好。
您也可以使用此腳本,只需更改高度和寬度
<canvas id="Canvas01" width="500" height="400" style="border:2px solid #FF9933; margin-left:10px; margin-top:10px;"></canvas>
<script>
var canvas = document.getElementById("Canvas01");
var ctx = canvas.getContext("2d");
聲明:本站的技術帖子網頁,遵循CC BY-SA 4.0協議,如果您需要轉載,請注明本站網址或者原文地址。任何問題請咨詢:yoyou2525@163.com.