使用JavaScript生成高质量PDF（jspdf + html2canvas）

Question

我一直在尝试通过单击页面上的按钮来从HTML页面转换并生成PDF，该按钮使用两个流行的插件自动生成并强制下载页面的PDF。* JSPDF* HTML2Canvas到目前为止，一切正常，但生成的PDF始终模糊且质量不高导入js文件（jquery，html2canvas，jspdf）后。这是我的JavaScript代码

function CreatePDFfromHTML() {
    var HTML_Width = $(".html-content").width();
    var HTML_Height = $(".html-content").height();
    var top_left_margin = 15;
    var PDF_Width = HTML_Width + (top_left_margin * 2);
    var PDF_Height = (PDF_Width * 1.5) + (top_left_margin * 2);
    var canvas_image_width = HTML_Width;
    var canvas_image_height = HTML_Height;

    var totalPDFPages = Math.ceil(HTML_Height / PDF_Height) - 1;

    html2canvas($(".html-content")[0]).then(function (canvas) {
        var imgData = canvas.toDataURL("image/jpeg", 1.0);
        var pdf = new jsPDF('p', 'pt', [PDF_Width, PDF_Height]);
        pdf.addImage(imgData, 'JPG', top_left_margin, top_left_margin, canvas_image_width, canvas_image_height);
        for (var i = 1; i <= totalPDFPages; i++) { 
            pdf.addPage(PDF_Width, PDF_Height);
            pdf.addImage(imgData, 'JPG', top_left_margin, -(PDF_Height*i)+(top_left_margin*4),canvas_image_width,canvas_image_height);
        }
        pdf.save("invoice_<?php echo $trackingNumber ;?>.pdf");
        $(".html-content").hide();
    });
}

我如何调整代码以使html2canvas将页面转换为质量更好的图像（消除模糊并使得生成的PDF文件更好）

Answer 1

经过几天的搜索，我终于找到了一种通过将HTML_weight和HTMLheight乘以3来提高质量的方法，这是新代码

function CreatePDFfromHTML() {
    var HTML_Width = $(".html-content").width()*3;
    var HTML_Height = $(".html-content").height()*3;
    var top_left_margin = 15;
    var PDF_Width = HTML_Width + (top_left_margin * 2);
    var PDF_Height = (PDF_Width * 1.5) + (top_left_margin * 2);
    var canvas_image_width = HTML_Width;
    var canvas_image_height = HTML_Height;

    var totalPDFPages = Math.ceil(HTML_Height / PDF_Height) - 1;

    html2canvas($(".html-content")[0]).then(function (canvas) {
        var imgData = canvas.toDataURL("image/jpeg", 1.0);
        var pdf = new jsPDF('p', 'pt', [PDF_Width, PDF_Height]);
        pdf.addImage(imgData, 'JPG', top_left_margin, top_left_margin, canvas_image_width, canvas_image_height);
        for (var i = 1; i <= totalPDFPages; i++) { 
            pdf.addPage(PDF_Width, PDF_Height);
            pdf.addImage(imgData, 'JPG', top_left_margin, -(PDF_Height*i)+(top_left_margin*4),canvas_image_width,canvas_image_height);
        }
        pdf.save("invoice_<?php echo $trackingNumber ;?>.pdf");
        $(".html-content").hide();
    });
}