This demo shows how to export a Dygraph object as a PNG image.
The current implementation creates a new canvas object from the plot and adds to it the axes and the legend. The resulting canvas is serialized to an image using the toDataURL() method.
Include the script dygraph-extra.js
and use the function
Dygraph.Export.asPNG(dygraph, img)
to render the dygraph
in the img element.
// g is a Dygraph object var g = new Dygraph(...); //demoimg is a the id of the <img> element where the dygraph will be exported. var img = document.getElementById('demoimg') // Create the image! Dygraph.Export.asPNG(dygraph, img); // The dygraph should be rendered in the <img> object and you should be able // to save it using your browser (e.g.: Right click, Save Image As)
(Hint: Update the image after changing zoom)
The font faces, sizes and colors can be specified passing an object as
the third argument for the function Dygraph.Export.asPNG
.
The following example shows how to do this and includes the available options and their default values:
// These are the default options var options = { //Texts displayed below the chart's x-axis and to the left of the y-axis titleFont: "bold 18px serif", titleFontColor: "black", //Texts displayed below the chart's x-axis and to the left of the y-axis axisLabelFont: "bold 14px serif", axisLabelFontColor: "black", // Texts for the axis ticks labelFont: "normal 12px serif", labelFontColor: "black", // Text for the chart legend legendFont: "bold 12px serif", legendFontColor: "black", legendHeight: 20 // Height of the legend area }; Dygraph.Export.asPNG(dygraph, img, options);
By Josep LlodrĂ Grimalt
The same data with both one and two y-axes. Two y-axes:
Dygraphs | PNG images |
---|---|
This program is distributed under the MIT license.
Sample code based on a Dygraph demo.
Last updated: 2012-09-25.