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Javascript 将画布元素分配给img.src_Javascript_Html_Canvas - Fatal编程技术网

Javascript 将画布元素分配给img.src

Javascript 将画布元素分配给img.src,javascript,html,canvas,Javascript,Html,Canvas,这很有效 img.src = "assets/img.png"; img.addEventListener('load', function () { textureContext.drawImage(this, 0, 0); texture.update(); }); 现在,如何使用页面上已经存在的canvas元素来插入这段代码。像这样的东西 var img = document.getElementById("canvas1"); textureContext.drawImag

这很有效

img.src = "assets/img.png";
img.addEventListener('load', function () {
   textureContext.drawImage(this, 0, 0);
   texture.update();
});
现在,如何使用页面上已经存在的canvas元素来插入这段代码。像这样的东西

var img = document.getElementById("canvas1");
textureContext.drawImage(img, 0, 0);
texture.update();

我正在寻找纯javascript解决方案。

您需要使用该方法

方法的作用是:返回一个数据URI,其中包含图像的表示形式,格式由类型参数指定(默认为PNG)。返回的图像分辨率为96 dpi

工作示例:

const canvas=document.getElementById(“canvas”);
const img_from_canvas=document.getElementById(“img_from_canvas”);
const context=canvas.getContext(“2d”);
rect(10,10,150,100);
context.fill();
img_from_canvas.src=canvas.toDataURL()
画布

画布上的图像

img.src = document.getElementById("canvas1").toDataURL();