js canvas获取图片base64 dataUrl

function getImgBase64(path,callback){ ???????var img = new Image(); ???????img.src = path; ???????//图片加载完成后触发 ???????img.onload = function(){ ???????var canvas = document.createElement("canvas"); ???????//获取绘画上下文 ???????ctx = canvas.getContext("2d"); ???????// 获取图片宽高 ???????var imgWidth = img.width; ???????var imgHeight = img.height; ???????//设置画布宽高与图片宽高相同 ???????canvas.width = imgWidth; ???????canvas.height = imgHeight; ???????//绘制图片 ???????ctx.drawImage(img,0,0,imgWidth,imgHeight); ???????//图片展示的 data URI ???????var dataUrl = canvas.toDataURL(‘image/jpeg‘); ???????callback ? callback(dataUrl) : ‘‘; ???????}; ???????} ???????getImgBase64(‘wood.png‘,function(dataUrl){ ???????console.log(dataUrl); ???????});