HTML5视频教程之html2canvas把div保存图片高清图的方法分享

var w = $("#code").width(); var h = $("#code").height(); //要将 canvas 的宽高设置成容器宽高的 2 倍 var canvas = document.createElement("canvas"); canvas.width = w * 2; canvas.height = h * 2; canvas.style.width = w + "px"; canvas.style.height = h + "px"; var context = canvas.getContext("2d"); //然后将画布缩放，将图像放大两倍画到画布上 context.scale(2,2); html2canvas(document.querySelector("#code"), { canvas: canvas, onrendered: function(canvas) { ... } });

.on('click','.download',function(){ $('#mycanvas').remove(); var _height=$('.skinReport').height(); //滚到顶部 $('html, body').animate({scrollTop:0}); if(confirm('是否下载肌肤检测报告？')) { setTimeout(function(){ var canvas = document.createElement("canvas"), w=$('#skinReport').width(), h=$('#skinReport').height(); canvas.width = w * 2; canvas.height = h * 2; canvas.style.width = w + "px"; canvas.style.height = h + "px"; var context = canvas.getContext("2d"); //然后将画布缩放，将图像放大两倍画到画布上 context.scale(2,2); html2canvas(document.getElementById('skinReport'), { allowTaint: false, taintTest: true, canvas: canvas, onrendered: function(canvas) { canvas.id = "mycanvas"; canvas.style.display = 'none'; document.body.appendChild(canvas); //生成base64图片数据 imgData = canvas.toDataURL(type); //var newImg = document.createElement("img"); //newImg.src = dataUrl; //document.body.appendChild(newImg); //console.log(imgData); var _fixType = function(type) { type = type.toLowerCase().replace(/jpg/i, 'jpeg'); var r = type.match(/png|jpeg|bmp|gif/)[0]; return 'image/' + r; }; // 加工image data，替换mime type imgData = imgData.replace(_fixType(type),'image/octet-stream'); /** * 在本地进行文件保存 * @param {String} data 要保存到本地的图片数据 * @param {String} filename 文件名 */ var saveFile = function(data, filename){ var save_link = document.createElementNS('http://www.w3.org/1999/xhtml', 'a'); save_link.href = data; save_link.download = filename; var event = document.createEvent('MouseEvents'); event.initMouseEvent('click', true, false, window, 0, 0, 0, 0, 0, false, false, false, false, 0, null); save_link.dispatchEvent(event); }; // 下载后的问题名 var filename = aname+'肌肤检测报告' + (new Date()).getTime() + '.' + type; // download saveFile(imgData,filename); }, width:1512, height:15000 }) },2500) } else { return; } })