11

我正在研究角度 vis.js。Vis.js 在画布上工作，用于创建节点和节点之间的链接。

有没有办法从 visj.s 画布中获取图像（jpeg/png）？

4

2 回答 2

13

看看这个片段，我认为它会对你有所帮助

在 vis 画布下，您将看到一个 PNG 图像。您可以右键单击此图像并保存。（或者您可以以任何其他标准方式保存它）

祝你好运。

// create an array with nodes
  var nodes = new vis.DataSet([
    {id: 1, label: 'Node 1'},
    {id: 2, label: 'Node 2'},
    {id: 3, label: 'Node 3'},
    {id: 4, label: 'Node 4'},
    {id: 5, label: 'Node 5'}
  ]);

  // create an array with edges
  var edges = new vis.DataSet([
    {from: 1, to: 3},
    {from: 1, to: 2},
    {from: 2, to: 4},
    {from: 2, to: 5}
  ]);

  // create a network
  var container = document.getElementById('mynetwork');
  var data = {
    nodes: nodes,
    edges: edges
  };
  var options = {};
  var network = new vis.Network(container, data, options);

  network.on("afterDrawing", function (ctx) {
    var dataURL = ctx.canvas.toDataURL();
    document.getElementById('canvasImg').src = dataURL;
  });
#mynetwork {
      width: 600px;
      height: 400px;
      border: 1px solid lightgray;
    }

    p {
      max-width: 600px;
    }
<!doctype html>
<html>
<head>
  <title>Network | Basic usage</title>
  <script type="text/javascript" src="https://cdnjs.cloudflare.com/ajax/libs/vis/4.20.0/vis.min.js"></script>
  <link href="https://cdnjs.cloudflare.com/ajax/libs/vis/4.20.0/vis.min.css" rel="stylesheet" type="text/css"/>
</head>
<body>

<div id="mynetwork"></div>
<pre id="eventSpan"></pre>
<img id="canvasImg" alt="Right click to save me!">



</body>
</html>

于 2017-06-28T06:38:15.783 回答
0

使它成为一个按钮：

network.on("afterDrawing", function(ctx) {
  var dataURL = ctx.canvas.toDataURL();
  document.getElementById('canvasImg').href = dataURL;
})
<input type="button" value="Download image" onclick="document.getElementById('canvasImg').click();">
<a id="canvasImg" download="filename"></a>

于 2021-11-07T17:25:04.537 回答