ChatGPT解决这个技术问题 Extra ChatGPT

How to modify the fill color of an SVG image when being served as background image?

Placing the SVG output directly inline with the page code I am able to simply modify fill colors with CSS like so:

polygon.mystar {
    fill: blue;
}​

circle.mycircle {
    fill: green;
}

This works great, however I'm looking for a way to modify the "fill" attribute of an SVG when it's being served as a BACKGROUND-IMAGE.

html {      
    background-image: url(../img/bg.svg);
}

How can I change the colors now? Is it even possible?

For reference, here are the contents of my external SVG file:

<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="320px" height="100px" viewBox="0 0 320 100" enable-background="new 0 0 320 100" xml:space="preserve">
<polygon class="mystar" fill="#3CB54A" points="134.973,14.204 143.295,31.066 161.903,33.77 148.438,46.896 151.617,65.43 134.973,56.679 
    118.329,65.43 121.507,46.896 108.042,33.77 126.65,31.066 "/>
<circle class="mycircle" fill="#ED1F24" cx="202.028" cy="58.342" r="12.26"/>
</svg>
I get hit up often with props for my answer. You should consider changing it to the accepted answer so it's not missed.
Your answer is certainly the winner here. Wish I had seen it 9 years ago!
2021 update: I'd argue that Adel's answer should be marked as the current "correct" answer.

A
Adel

You can use CSS masks, With the 'mask' property, you create a mask that is applied to an element.

.icon {
    background-color: red;
    -webkit-mask-image: url(icon.svg);
    mask-image: url(icon.svg);
}

For more see this great article: https://codepen.io/noahblon/post/coloring-svgs-in-css-background-images


this is good but when applied to an icon within an input field all the input text is hidden.
Not supported in IE
Summer 2019: 94% of browsers on this planet support "mask-image" OR "-webkit-mask-image" styles
This answer is getting a lot more attention lately so I thought I should point out it is NOT a background image. This masks off the whole element including it's contents. If I wanted to dedicate an element to the image, I could just use a normal SVG with a fill set. Masking is useful for some cases but I dont think it really qualifies as an answer to this particular question.
@cronoklee - While you're techincally correct, mask-image effectively can be used to create a "background image". To use this approach on Element A when masking is not desired, create an Element B (using any method you prefer) that has the same position and dimensions as Element A and apply the mask-image to Element B.
R
Ryan

I needed something similar and wanted to stick with CSS. Here are LESS and SCSS mixins as well as plain CSS that can help you with this. Unfortunately, it's browser support is a bit lax. See below for details on browser support.

LESS mixin:

.element-color(@color) {
  background-image: url('data:image/svg+xml;utf8,<svg ...><g stroke="@{color}" ... /></g></svg>');
}

LESS usage:

.element-color(#fff);

SCSS mixin:

@mixin element-color($color) {
  background-image: url('data:image/svg+xml;utf8,<svg ...><g stroke="#{$color}" ... /></g></svg>');
}

SCSS usage:

@include element-color(#fff);

CSS:

// color: red
background-image: url('data:image/svg+xml;utf8,<svg ...><g stroke="red" ... /></g></svg>');

Here is more info on embedding the full SVG code into your CSS file. It also mentioned browser compatibility which is a bit too small for this to be a viable option.


Note that you must urlencode the # character for your hex colors to make this work in Firefox. So something like <svg fill="#ffffff" ...></svg> becomes <svg fill="%23ffffff" ...></svg>.
Sweet method. Do you have to hard encode the svg into the background-image like that? Can you not just link out to it somehow?
Problem with this method is that you miss out on browser cache.
I found this site useful for giving you the perfectly encoded URL ready for use: yoksel.github.io/url-encoder - Just copy the SVG code into it and copy out the returned CSS :-)
I went this way, only to realise its blocked in production by any reverse proxy with decent security hearders, as explained here: stackoverflow.com/a/62213224/5506400. This was is vunerable to XSS attacks.
D
David Neto

One way to do this is to serve your svg from some server side mechanism. Simply create a resource server side that outputs your svg according to GET parameters, and you serve it on a certain url.

Then you just use that url in your css.

Because as a background img, it isn't part of the DOM and you can't manipulate it. Another possibility would be to use it regularly, embed it in a page in a normal way, but position it absolutely, make it full width & height of a page and then use z-index css property to put it behind all the other DOM elements on a page.


Don't forget if you're serving the SVG from a server-side script, to make sure you also send the correct MIME header. In PHP this would be: <?php header('Content-type: image/svg+xml'); ?>
You can use the svg image as mask and manipulate the background-color of the element. This will have the same effect as changing the fill. (detailed answer provided)
This answer was great as of 2012, but now CSS masks and/or filters have been supported in all browsers for some time. I recommend that anyone reading this now check out the links in widged's answer below or just skip to CSS Masks here, which is a really easy solution -- note it still requires 2 version of the rule, one with -webkit- prefix at the present time. For Microsoft Edge, currently CSS filters are supported but not yet masks.
There are many solutions provide bellow that work nowadays, I agree this answer no longer reflects the current state of possibilities.
Another issue with this solution is that for each color you need, you will make one more HTTP request, instead of fetching once and styling with filter or mask-image.
w
widged

Yet another approach is to use mask. You then change the background color of the masked element. This has the same effect as changing the fill attribute of the svg.

HTML:

<glyph class="star"/>
<glyph class="heart" />
<glyph class="heart" style="background-color: green"/>
<glyph class="heart" style="background-color: blue"/>

CSS:

glyph {
    display: inline-block;
    width:  24px;
    height: 24px;
}

glyph.star {
  -webkit-mask: url(star.svg) no-repeat 100% 100%;
  mask: url(star.svg) no-repeat 100% 100%;
  -webkit-mask-size: cover;
  mask-size: cover;
  background-color: yellow;
}

glyph.heart {
  -webkit-mask: url(heart.svg) no-repeat 100% 100%;
  mask: url(heart.svg) no-repeat 100% 100%;
  -webkit-mask-size: cover;
  mask-size: cover;
  background-color: red;
}

You will find a full tutorial here: http://codepen.io/noahblon/blog/coloring-svgs-in-css-background-images (not my own). It proposes a variety of approaches (not limited to mask).


One thing to note on this is browser support. I believe IE (as usual) is way behind on this.
Unfortunately mask is neither supported by IE nor Edge: caniuse.com/#search=mask
Not working for me in Chrome either. Edit: Oh nvm... I don't have autoprefixer enabled. I thought vendors were supposed to stop using prefixes?!
Works in latest chrome and firefox
@alpipego Update! Edge added support for mask-image in late 2017.
p
priyaqb

Use the sepia filter along with hue-rotate, brightness, and saturation to create any color we want.

.colorize-pink {
  filter: brightness(0.5) sepia(1) hue-rotate(-70deg) saturate(5);
}

https://css-tricks.com/solved-with-css-colorizing-svg-backgrounds/


Use this CSS filter generator: codepen.io/sosuke/pen/Pjoqqp
Yes this should be the answer. Follow the css filter generator instructions from @djibe above.
This does not answer the question. what if he wants to fill different paths with different color?
This was incredibly helpful to me, along with @djibe 's comment
This is brilliant! I knew the filter sepia/hue-rotate trick but didn't think to look for a generator! \o/
P
Philipp Kühn

It's possible with Sass! The only thing you have to do is to url-encode your svg code. And this is possible with a helper function in Sass. I've made a codepen for this. Look at this:

http://codepen.io/philippkuehn/pen/zGEjxB

// choose a color

$icon-color: #F84830;


// functions to urlencode the svg string

@function str-replace($string, $search, $replace: '') {
  $index: str-index($string, $search);
  @if $index {
    @return str-slice($string, 1, $index - 1) + $replace + str-replace(str-slice($string, $index + str-length($search)), $search, $replace);
  }
  @return $string;
}

@function url-encode($string) {
  $map: (
    "%": "%25",
    "<": "%3C",
    ">": "%3E",
    " ": "%20",
    "!": "%21",
    "*": "%2A",
    "'": "%27",
    '"': "%22",
    "(": "%28",
    ")": "%29",
    ";": "%3B",
    ":": "%3A",
    "@": "%40",
    "&": "%26",
    "=": "%3D",
    "+": "%2B",
    "$": "%24",
    ",": "%2C",
    "/": "%2F",
    "?": "%3F",
    "#": "%23",
    "[": "%5B",
    "]": "%5D"
  );
  $new: $string;
  @each $search, $replace in $map {
    $new: str-replace($new, $search, $replace);
  }
  @return $new;
}

@function inline-svg($string) {
  @return url('data:image/svg+xml;utf8,#{url-encode($string)}');
}


// icon styles
// note the fill="' + $icon-color + '"

.icon {
  display: inline-block;
  width: 50px;
  height: 50px;
  background: inline-svg('<svg version="1.1" xmlns="http://www.w3.org/2000/svg" xmlns:xlink="http://www.w3.org/1999/xlink" x="0px" y="0px"
   viewBox="0 0 30 30" enable-background="new 0 0 30 30" xml:space="preserve">
<path fill="' + $icon-color + '" d="M18.7,10.1c-0.6,0.7-1,1.6-0.9,2.6c0,0.7-0.6,0.8-0.9,0.3c-1.1-2.1-0.4-5.1,0.7-7.2c0.2-0.4,0-0.8-0.5-0.7
  c-5.8,0.8-9,6.4-6.4,12c0.1,0.3-0.2,0.6-0.5,0.5c-0.6-0.3-1.1-0.7-1.6-1.3c-0.2-0.3-0.4-0.5-0.6-0.8c-0.2-0.4-0.7-0.3-0.8,0.3
  c-0.5,2.5,0.3,5.3,2.1,7.1c4.4,4.5,13.9,1.7,13.4-5.1c-0.2-2.9-3.2-4.2-3.3-7.1C19.6,10,19.1,9.6,18.7,10.1z"/>
</svg>');
}

This works very good. Only problem: In IE10 the icon is way too small (i think 10% of given size.
A
Albaz
 .icon { 
  width: 48px;
  height: 48px;
  display: inline-block;
  background: url(https://s3-us-west-2.amazonaws.com/s.cdpn.io/18515/heart.svg) no-repeat 50% 50%; 
  background-size: cover;
}

.icon-orange { 
  -webkit-filter: hue-rotate(40deg) saturate(0.5) brightness(390%) saturate(4); 
  filter: hue-rotate(40deg) saturate(0.5) brightness(390%) saturate(4); 
}

.icon-yellow {
  -webkit-filter: hue-rotate(70deg) saturate(100);
  filter: hue-rotate(70deg) saturate(100);
}

codeben article and demo


This method will apply filter to a whole object, including children.
t
tnt-rox

Now you can achieve this on the client side like this:

var green = '3CB54A';
var red = 'ED1F24';
var svg = '<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="320px" height="100px" viewBox="0 0 320 100" enable-background="new 0 0 320 100" xml:space="preserve"> <polygon class="mystar" fill="#'+green+'" points="134.973,14.204 143.295,31.066 161.903,33.77 148.438,46.896 151.617,65.43 134.973,56.679 118.329,65.43 121.507,46.896 108.042,33.77 126.65,31.066 "/><circle class="mycircle" fill="#'+red+'" cx="202.028" cy="58.342" r="12.26"/></svg>';      
var encoded = window.btoa(svg);
document.body.style.background = "url(data:image/svg+xml;base64,"+encoded+")";

Fiddle here!


You should avoid the use of Base64 for SVG as it is unnecessary, makes your files bigger and even prevents GZIP from effectively compressing those chunks of code.
This encoding is happening on the client side, probably just for thorough escaping...
It goes without saying you can do anything with JS. The point is to avoid JS.
C
Community

Download your svg as text.

Modify your svg text using javascript to change the paint/stroke/fill color[s].

Then embed the modified svg string inline into your css as described here.


A
António Almeida

If you are trying to use and SVG directly on CSS with url() like this;

a:before {
  content: url('data:image/svg+xml; utf8, <svg xmlns="http://www.w3.org/2000/svg" x="0" y="0" viewBox="0 0 451 451"><path d="M345.441,2...

You should encode the # to %23, otherwise it won't work.

<svg fill="%23FFF" ...

G
Gajus

You can store the SVG in a variable. Then manipulate the SVG string depending on your needs (i.e., set width, height, color, etc). Then use the result to set the background, e.g.

$circle-icon-svg: '<svg xmlns="http://www.w3.org/2000/svg"><circle cx="10" cy="10" r="10" /></svg>';

$icon-color: #f00;
$icon-color-hover: #00f;

@function str-replace($string, $search, $replace: '') {
    $index: str-index($string, $search);

    @if $index {
        @return str-slice($string, 1, $index - 1) + $replace + str-replace(str-slice($string, $index + str-length($search)), $search, $replace);
    }

    @return $string;
}

@function svg-fill ($svg, $color) {
  @return str-replace($svg, '<svg', '<svg fill="#{$color}"');
}

@function svg-size ($svg, $width, $height) {
  $svg: str-replace($svg, '<svg', '<svg width="#{$width}"');
  $svg: str-replace($svg, '<svg', '<svg height="#{$height}"');

  @return $svg;
}

.icon {
  $icon-svg: svg-size($circle-icon-svg, 20, 20);

  width: 20px; height: 20px; background: url('data:image/svg+xml;utf8,#{svg-fill($icon-svg, $icon-color)}');

  &:hover {
    background: url('data:image/svg+xml;utf8,#{svg-fill($icon-svg, $icon-color-hover)}');
  }
}

I have made a demo too, http://sassmeister.com/gist/4cf0265c5d0143a9e734.

This code makes a few assumptions about the SVG, e.g. that <svg /> element does not have an existing fill colour and that neither width or height properties are set. Since the input is hardcoded in the SCSS document, it is quite easy to enforce these constraints.

Do not worry about the code duplication. compression makes the difference negligible.


Duplicate code is a code smell so suggesting people should not worry about duplicate code in the case of your example is not a good idea, however that said I can't see where your code is duplicated? I think it would read better if you just removed the comment altogether.
a
arielhad

You can use the brightness filter, any value greater than 1 makes the element brighter, and any value less than 1 makes it darker. So, we can make those light SVG’s dark, and vice versa, for example, this will make the svg darker:

filter: brightness(0);

In order to change the color and not only brightness level we can use sepia filter along with hue-rotate, brightness, for example:

.colorize-blue {
  filter: brightness(0.5) sepia(1) hue-rotate(140deg) saturate(6);
}

L
Lomax

You can create your own SCSS function for this. Adding the following to your config.rb file.

require 'sass'
require 'cgi'

module Sass::Script::Functions

  def inline_svg_image(path, fill)
    real_path = File.join(Compass.configuration.images_path, path.value)
    svg = data(real_path)
    svg.gsub! '{color}', fill.value
    encoded_svg = CGI::escape(svg).gsub('+', '%20')
    data_url = "url('data:image/svg+xml;charset=utf-8," + encoded_svg + "')"
    Sass::Script::String.new(data_url)
  end

private

  def data(real_path)
    if File.readable?(real_path)
      File.open(real_path, "rb") {|io| io.read}
    else
      raise Compass::Error, "File not found or cannot be read: #{real_path}"
    end
  end

end

Then you can use it in your CSS:

.icon {
  background-image: inline-svg-image('icons/icon.svg', '#555');
}

You will need to edit your SVG files and replace any fill attributes in the markup with fill="{color}"

The icon path is always relative to your images_dir parameter in the same config.rb file.

Similar to some of the other solutions, but this is pretty clean and keeps your SCSS files tidy!


this is from a github-issue. Just referencing it here in case somebody wants to read the discussion there
M
Michaël van de Weerd

In some (very specific) situations this might be achieved by using a filter. For example, you can change a blue SVG image to purple by rotating the hue 45 degrees using filter: hue-rotate(45deg);. Browser support is minimal but it's still an interesting technique.

Demo


M
Mark Overton

for monochrome background you could use a svg with a mask, where the background color should be displayed

<svg xmlns="http://www.w3.org/2000/svg" viewBox="0 0 20 20" preserveAspectRatio="xMidYMid meet" focusable="false" style="pointer-events: none; display: block; width: 100%; height: 100%;" >
    <defs>
        <mask id="Mask">
            <rect width="100%" height="100%" fill="#fff" />
            <polyline stroke-width="2.5" stroke="black" stroke-linecap="square" fill="none" transform="translate(10.373882, 8.762969) rotate(-315.000000) translate(-10.373882, -8.762969) " points="7.99893906 13.9878427 12.7488243 13.9878427 12.7488243 3.53809523"></polyline>
        </mask>
    </defs>
    <rect x="0" y="0" width="20" height="20" fill="white" mask="url(#Mask)" />
</svg>

and than use this css

background-repeat: no-repeat;
background-position: center center;
background-size: contain;
background-image: url(your/path/to.svg);
background-color: var(--color);

E
Eleanor Zimmermann

Late to the show here, BUT, I was able to add a fill color to the SVG polygon, if you're able to directly edit the SVG code, so for example the following svg renders red, instead of default black. I have not tested outside of Chrome though:

<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="500px" height="500px" viewBox="0 0 500 500" enable-background="new 0 0 500 500" xml:space="preserve">
    <polygon 


        fill="red"


        fill-rule="evenodd" clip-rule="evenodd" points="452.5,233.85 452.5,264.55 110.15,264.2 250.05,390.3 229.3,413.35 
47.5,250.7 229.3,86.7 250.05,109.75 112.5,233.5 "/>
</svg>

S
SequenceDigitale.com

The only way i found for this, and to be cross browser (aka bulletproof), is to render the SVG with PHP and pass Query String to set the color.

The SVG, here called "arrow.php"

<?php
$fill = filter_input(INPUT_GET, 'fill');
$fill = strtolower($fill);
$fill = preg_replace("/[^a-z0-9]/", '', $fill);
if(empty($fill)) $fill = "000000";
header('Content-type: image/svg+xml');
echo '<?xml version="1.0" encoding="utf-8"?>';
?>
<svg xmlns="http://www.w3.org/2000/svg" width="7.4" height="12" viewBox="0 0 7.4 12">
    <g>
        <path d="M8.6,7.4,10,6l6,6-6,6L8.6,16.6,13.2,12Z" transform="translate(-8.6 -6)" fill="#<?php echo htmlspecialchars($fill); ?>" fill-rule="evenodd"/>
    </g>
</svg>

Then you call the image like this

.cssclass{ background-image: url(arrow.php?fill=112233); }

Works only with PHP. And remember that everytime you change the color value, your browser will load a new image.


D
Daniil

scss create function

@function url-svg($icon) {
  @return url("data:image/svg+xml;utf8,#{str-replace($icon, "#", "%23")}");
}

scss use

url-svg('<svg width="15" height="15" viewBox="0 0 15 15" fill="none" xmlns="http://www.w3.org/2000/svg"><path d="M13.125 0H1.875C0.84082 0 0 0.84082 0 1.875V10.3125C0 11.3467 0.84082 12.1875 1.875 12.1875H4.6875V14.6484C4.6875 14.9355 5.01563 15.1025 5.24707 14.9326L8.90625 12.1875H13.125C14.1592 12.1875 15 11.3467 15 10.3125V1.875C15 0.84082 14.1592 0 13.125 0Z" fill="#8A8A8F"/></svg>')

css generated

url('data:image/svg+xml;utf8,<svg width="15" height="15" viewBox="0 0 15 15" fill="none" xmlns="http://www.w3.org/2000/svg"><path d="M13.125 0H1.875C0.84082 0 0 0.84082 0 1.875V10.3125C0 11.3467 0.84082 12.1875 1.875 12.1875H4.6875V14.6484C4.6875 14.9355 5.01563 15.1025 5.24707 14.9326L8.90625 12.1875H13.125C14.1592 12.1875 15 11.3467 15 10.3125V1.875C15 0.84082 14.1592 0 13.125 0Z" fill="%238A8A8F"/></svg>')

The str-replace function is used from bootstrap.


f
fdrv

If you wanna swap in a simple way from white to black or some like that, Simple try

filter: invert(100%);

M
Mebin Benny

This is my favorite method, but your browser support must be very progressive. With the mask property you create a mask that is applied to an element. Everywhere the mask is opaque, or solid, the underlying image shows through. Where it’s transparent, the underlying image is masked out, or hidden. The syntax for a CSS mask-image is similar to background-image.look at the codepenmask


A
A2D

A lot of IFs, but if your pre base64 encoded SVG starts:

<svg fill="#000000

Then the base64 encoded string will start:

PHN2ZyBmaWxsPSIjMDAwMDAw

if the pre-encoded string starts:

<svg fill="#bfa76e

then this encodes to:

PHN2ZyBmaWxsPSIjYmZhNzZl

Both encoded strings start the same:

PHN2ZyBmaWxsPSIj

The quirk of base64 encoding is every 3 input characters become 4 output characters. With the SVG starting like this then the 6-character hex fill color starts exactly on an encoding block 'boundary'. Therefore you can easily do a cross-browser JS replace:

output = input.replace(/MDAwMDAw/, "YmZhNzZl");

But tnt-rox answer above is the way to go moving forward.


It seems public disliked the base64 use
This is ridiculous to write by hand but a great small lib idea. Bascially, base64 encode just parts of svg, swap as needed. (In my solution, I'm doing same but via components, pretty much free when prerendering vue, so no need for base64 here)
@revelt - this was written in 2016, SVG data-uris HAD to be base 64 encoded. Lot's has changed thankfully