Javascript 如何使用html2canvas在下载的pdf中捕获徽标和当前日期

我正在使用jspdf打印和下载pdf格式的div内容。在这里，我还需要以pdf格式捕获页面左上角的图像和页面右上角的当前日期作为我的html。可能需要在html2canvas中使用position和addimage。我是html2canvas的新手，有人能帮我吗？这是代码

html

---

尝试在base64中转换图像

var src = 'data:image/png;base64,iVBORw0K.......'
//doc.addImage(src, 'PNG', x, y, w, h);
doc.addImage(src, 'PNG', 0, 240, 210, 57);

$(document).ready(function() {
var today = new Date();
var dd = today.getDate();
var mm = today.getMonth()+1; //January is 0!
var yyyy = today.getFullYear();

if(dd<10) {
    dd = '0'+dd
} 

if(mm<10) {
    mm = '0'+mm
} 

today = mm + '/' + dd + '/' + yyyy;
$('#date').append(today);
      $('#print').click(function() {
     var currentPosition = document.getElementById("content").scrollTop;
      var w = document.getElementById("content").offsetWidth;
      var h = document.getElementById("content").offsetHeight;
     document.getElementById("content").style.height="auto";

      html2canvas(document.getElementById("content"), {

        dpi: 300, // Set to 300 DPI
        scale: 3, // Adjusts your resolution
        onrendered: function(canvas) {
          var img = canvas.toDataURL("image/jpeg", 1);
          var doc = new jsPDF('L', 'px', [w, h]);
          doc.addImage(img, 'JPEG', 0, 0, w, h);
          doc.addPage();
          doc.save('sample-file.pdf');
        }
      });
     document.getElementById("content").style.height="100px";
     document.getElementById("content").scrollTop = currentPosition;
    });

    });

body {
      background: beige;
    }

    header {
      background: red;
    }

    footer {
      background: blue;
    }

    #content {
      background: yellow;
      width: 70%;
      height: 100px;
      margin: 50px auto;
      border: 1px solid orange;
      padding: 20px;
      overflow-y:auto;
    }
    .html2canvas-container { width: 3000px !important; height: 3000px !important; }container { width: 3000px !important; height: 5000px !important; }

var src = 'data:image/png;base64,iVBORw0K.......'
//doc.addImage(src, 'PNG', x, y, w, h);
doc.addImage(src, 'PNG', 0, 240, 210, 57);