Welcome to ShenZhenJia Knowledge Sharing Community for programmer and developer-Open, Learning and Share
menu search
person
Welcome To Ask or Share your Answers For Others

Categories

Can you serialize/deserialize a canvas object in javascript?

See Question&Answers more detail:os

与恶龙缠斗过久,自身亦成为恶龙;凝视深渊过久,深渊将回以凝视…
thumb_up_alt 0 like thumb_down_alt 0 dislike
415 views
Welcome To Ask or Share your Answers For Others

1 Answer

Besides the getImageData method, you can use canvas.toDataURL() to get an data-URL-encoded PNG. If you need to serialize to a string, it would save having to convert the raw data to a string manually. You could deserialize by creating an image and setting the src to the data URL, then drawing it to a canvas.

[Edited to account for asynchronous loading (suggested by olliej).]

function serialize(canvas) {
    return canvas.toDataURL();
}

function deserialize(data, canvas) {
    var img = new Image();
    img.onload = function() {
        canvas.width = img.width;
        canvas.height = img.height;
        canvas.getContext("2d").drawImage(img, 0, 0);
    };

    img.src = data;
}

If I remember correctly, some older versions of Safari, and maybe Opera didn't support toDataURL, but the more recent versions do.


与恶龙缠斗过久,自身亦成为恶龙;凝视深渊过久,深渊将回以凝视…
thumb_up_alt 0 like thumb_down_alt 0 dislike
Welcome to ShenZhenJia Knowledge Sharing Community for programmer and developer-Open, Learning and Share
...