Question

我已完成截图按钮，必须制作所有正文的屏幕截图。

但在此屏幕截图中，谷歌地图并未显示出来。我使用html2canvas库来做到这一点。这是代码：

HTML：

 <button type="button" class="btn btn-default btn-sm" id = 'screenShotBtn' onclick="takeScreenShot()">

JAVASCRIPT：

var takeScreenShot = function() {
var screenshot = {};
html2canvas(document.getElementById('screenAll'), {
    onrendered: function (canvas) {
        var tempcanvas=document.createElement('canvas');
        tempcanvas.width=1350;
        tempcanvas.height=700;
        var context=tempcanvas.getContext('2d');
        context.drawImage(canvas,0,0,1350,700,0,0,1350,700);
        var link=document.createElement("a");
        link.href=tempcanvas.toDataURL('image/jpg');   //function blocks CORS
        link.download = 'screenshot.jpg';
        link.click();
    }
});

以下是制作屏幕截图时的内容：

look here for screenshot

你能告诉我什么错了吗？

Answer 1

我将这些属性添加到代码中并且可以正常工作：

var takeScreenShot = function() {
    var screenshot = {};
    html2canvas(document.getElementById('map'), {
        useCORS: true,
        optimized: false,
        allowTaint: false,
        onrendered: function (canvas) {
            var tempcanvas=document.createElement('canvas');
            tempcanvas.width=1350;
            tempcanvas.height=700;
            var context=tempcanvas.getContext('2d');
            context.drawImage(canvas,0,0,1350,700,0,0,1350,700);
            var link=document.createElement("a");
            link.href=tempcanvas.toDataURL('image/jpg');   //function blocks CORS
            link.download = 'screenshot.jpg';
            link.click();
        }
    });
}

Answer 2

我认为这是Chrome中存在的一个已知问题。

您可以尝试我找到的解决方法：

 if(window.chrome) {// Fix for Chrome
    var transform=$(".gm-style>div:first>div").css("transform");
    var comp=transform.split(","); //split up the transform matrix
    var mapleft=parseFloat(comp[4]); //get left value
    var maptop=parseFloat(comp[5]);  //get top value
    $(".gm-style>div:first>div").css({ //get the map container. not sure if stable
      "transform":"none",
      "left":mapleft,
      "top":maptop,
    });
  }

  html2canvas([$("#map > div.g-map-canvas > div > div > div:nth-child(1)")[0]], {
    logging: false,
    useCORS: true,
    onrendered: function (canvas) {
      $('#screenshot').after(canvas);

      if(window.chrome) {// Fix for Chrome
        $(".gm-style>div:first>div").css({
          left:0,
          top:0,
          "transform":transform
        });
      }
    }
  });

链接到原始主题：https://github.com/niklasvh/html2canvas/issues/345

Answer 3

    var fin = document.getElementById("map");

    html2canvas(fin, {
    useCORS: true,
    onrendered: function(canvas) {
        var dataUrl= canvas.toDataURL("image/png");
        $('#map_image').attr('src',dataUrl).show();
    }
  });

使用html2canvas时不会显示Google Map

3 个答案: