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How to access SVG elements with Javascript

I'm messing around with SVG and I was hoping I could create SVG files in Illustrator and access elements with Javascript.

Here's the SVG file Illustrator kicks out (It also seems to add a load of junk to the beginning of the file that I've removed)

<?xml version="1.0" encoding="utf-8"?>
<!DOCTYPE svg PUBLIC "-//W3C//DTD SVG 1.1//EN" "http://www.w3.org/Graphics/SVG/1.1/DTD/svg11.dtd">
<svg version="1.1" id="Layer_1" xmlns="http://www.w3.org/2000/svg" xmlns:xlink="http://www.w3.org/1999/xlink" x="0px" y="0px"
     width="276.843px" height="233.242px" viewBox="0 0 276.843 233.242" enable-background="new 0 0 276.843 233.242"
     xml:space="preserve">
<path id="delta" fill="#231F20" d="M34.074,86.094L0,185.354l44.444,38.519l80.741-0.74l29.63-25.186l-26.667-37.037
    c0,0-34.815-5.926-37.778-6.667s-13.333-28.889-13.333-28.889l7.407-18.519l31.111-2.963l5.926-21.481l-12.593-38.519l-43.704-5.185
    L34.074,86.094z"/>
<path id="cargo" fill="#DFB800" d="M68.148,32.761l43.704,4.445l14.815,42.963l-7.407,26.667l-33.333,2.963l-4.444,14.074
    l54.074-1.481l22.222,36.296l25.926-3.704l25.926-54.074c0,0-19.259-47.408-21.481-47.408s-31.852-0.741-31.852-0.741
    l-19.259-39.259L92.593,8.316L68.148,32.761z"/>
<polygon id="beta" fill="#35FF1F" points="86.722,128.316 134.593,124.613 158.296,163.872 190.889,155.724 214.593,100.909 
    194.593,52.02 227.186,49.057 246.444,92.02 238.297,140.909 216.074,172.761 197.556,188.316 179.778,169.798 164.963,174.983 
    163.481,197.946 156.815,197.946 134.593,159.428 94.593,151.279 "/>
<path class="monkey" id="alpha" fill="#FD00FF" d="M96.315,4.354l42.963,5.185l18.519,42.222l71.852-8.148l20.74,46.667l-5.926,52.593
    l-24.444,34.074l-25.185,15.555l-14.074-19.259l-8.889,2.964l-1.481,22.222l-14.074,2.963l-25.186,22.963l-74.074,4.444
    l101.481,4.444c0,0,96.297-17.777,109.63-71.852S282.24,53.983,250.389,20.65S96.315,4.354,96.315,4.354z"/>
</svg>

As you can probably see, each element has an ID, and I was hoping to be able to access individual elements with Javascript so I could change the Fill attribute and respond to events such as click.

The HTML is bog basic

<!DOCTYPE html>
<html>
    <head>
        <title>SVG Illustrator Test</title> 
    </head>
    <body>

        <object data="alpha.svg" type="image/svg+xml" id="alphasvg" width="100%" height="100%"></object>

    </body>
</html>

I guess this is two questions really.

Is it possible to do it this way, as opposed to using something like Raphael or jQuery SVG. If it is possible, what's the technique?

UPDATE

At the moment, I've resorted to using Illustrator to create the SVG file, and I'm using Raphaël JS to create paths and simply copying the point data from the SVG file and pasting it into path() function. Creating complex paths such as might be needed for a map, by coding the point data manually is (to my knowledge) prohibitively complex.


H
Hien Nguyen

Is it possible to do it this way, as opposed to using something like Raphael or jQuery SVG?

Definitely.

If it is possible, what's the technique?

This annotated code snippet works:

<!DOCTYPE html>
<html>
    <head>
        <title>SVG Illustrator Test</title> 
    </head>
    <body>

        <object data="alpha.svg" type="image/svg+xml"
         id="alphasvg" width="100%" height="100%"></object>

        <script>
            var a = document.getElementById("alphasvg");

            // It's important to add an load event listener to the object,
            // as it will load the svg doc asynchronously
            a.addEventListener("load",function(){

                // get the inner DOM of alpha.svg
                var svgDoc = a.contentDocument;
                // get the inner element by id
                var delta = svgDoc.getElementById("delta");
                // add behaviour
                delta.addEventListener("mousedown",function(){
                        alert('hello world!')
                }, false);
            }, false);
        </script>
    </body>
</html>

Note that a limitation of this technique is that it is restricted by the same-origin policy, so alpha.svg must be hosted on the same domain as the .html file, otherwise the inner DOM of the object will be inaccessible.

Important thing to run this HTML, you need host HTML file to web server like IIS, Tomcat


a note on @jbeard4 's note: in some browsers this same-origin policy results in the need to use a server (even if you code is only using html and js [serverside]) the access policy will prevent access to the svg.
Important thing to run this HTML, you need host HTML file to web server like IIS, Tomcat
As @HienNguyen mentioned, before running it on a web server, It did not work. The value returned for document.getElementById("alphasvg").contentDocument was null.
TL;DR: contentDocument bridges from the HTML context to the SVG context
l
lambda

In case you use jQuery you need to wait for $(window).load, because the embedded SVG document might not be yet loaded at $(document).ready

$(window).load(function () {

    //alert("Document loaded, including graphics and embedded documents (like SVG)");
    var a = document.getElementById("alphasvg");

    //get the inner DOM of alpha.svg
    var svgDoc = a.contentDocument;

    //get the inner element by id
    var delta = svgDoc.getElementById("delta");
    delta.addEventListener("mousedown", function(){ alert('hello world!')}, false);
});

While using this code, this other answer might be a useful complement: stackoverflow.com/a/5990945/1515819
in case of jQuery you'd better use $('#alphasvg').load instead of $(window).load. This will allow you to change attribute data on the fly
Note that while you can use jQuery to access elements within svg, you cannot use it to append elements to an svg. See stackoverflow.com/questions/3642035/… for why.
D
Drew Noakes

If you are using an <img> tag for the SVG, then you cannot manipulate its contents (as far as I know).

As the accepted answer shows, using <object> is an option.

I needed this recently and used gulp-inject during my gulp build to inject the contents of an SVG file directly into the HTML document as an <svg> element, which is then very easy to work with using CSS selectors and querySelector/getElementBy*.


img tag is useful to big SVG load... To use complex (and interactive!) SVG the better to use D3js, that is like a lite jQuery, specialized in SVG+DOM+data manipulation.