PDF文件解析渲染 打印PDF文件内容 pdfjsLib

整体思路：

1.使用pdfjsLib解析 文件

2.canvas画出解析文件

3.转化url并且打印

const page = await pdfDocument.getPage(i);

const viewport = page.getViewport({ scale: 1.32 });

const headerHeight = 60;

const totalCanvas = document.createElement('canvas');

const ctx = totalCanvas.getContext('2d');

totalCanvas.width = viewport.width;

totalCanvas.height = viewport.height + headerHeight;

ctx.fillStyle = '#f0f0f0';

ctx.fillRect(0, 0, totalCanvas.width, 300);

ctx.fillStyle = '#333333';

ctx.font = '25px Arial';

ctx.fillText(customerCode + ' | ' + '' + 'DUE DATE: ' + dueDate, 170, headerHeight - 20);

const qrDataUrl = generateQRCodeDataUrl(customerCode, 40, 40);

const qrImg = new Image();

await new Promise((resolve, reject) => {

qrImg.onload = resolve;

qrImg.onerror = reject;

qrImg.src = qrDataUrl;

});

ctx.drawImage(qrImg, totalCanvas.width - 70, 10, 40, 40);

const renderContext = {

canvasContext: ctx,

viewport: viewport

};

ctx.save();

ctx.translate(0, headerHeight);

await page.render(renderContext).promise;

ctx.restore();

const imageDataUrl = totalCanvas.toDataURL('image/png');

图片地址出来后 就随便打印了 还是蛮清晰的 over！