How to import an entire folder of SVG images (or how to load them dynamically) into a React Web App?

If using React, I strongly suspect you are also using Webpack. You can use require.context instead of es6 import and Webpack will resolve it for you when building.

require.context ( folder, recurse, pattern )

• folder - String - Path to folder to begin scanning for files.
• recurse - Boolean - Whether to recursively scan the folder.
• pattern - RegExp - Matching pattern describing which files to include.

The first line of each example ...

const reqSvgs = require.context ( './images', true, /\.svg$/ )

... creates a Require Context mapping all the *.svg file paths in the images folder to an import. This gives us a specialized Require Function named reqSvgs with some attached properties.

One of the properties of reqSvgs is a keys method, which returns a list of all the valid filepaths.

const allSvgFilepaths = reqSvgs.keys ()

We can pass one of those filepaths into reqSvgs to get an imported image.

const imagePath = allSvgFilePaths[0]
const image = reqSvgs ( imagePath )

This api is constraining and unintuitive for this use case, so I suggest converting the collection to a more common JavaScript data structure to make it easier to work with.

Every image will be imported during the conversion. Take care, as this could be a foot-gun. But it provides a reasonably simple mechanism for copying multiple files to the build folder which might never be explicitly referenced by the rest of your source code.

Here are 3 example conversions that might be useful.

---

Array

Create an array of the imported files.

const reqSvgs = require.context ( './images', true, /\.svg$/ )
const paths = reqSvgs.keys ()

const svgs = paths.map( path => reqSvgs ( path ) )

Array of Objects

Create an array of objects, with each object being { path, file } for one image.

const reqSvgs = require.context ( './images', true, /\.svg$/ )

const svgs = reqSvgs
  .keys ()
  .map ( path => ({ path, file: reqSvgs ( path ) }) )

Plain Object

Create an object where each path is a key to its matching file.

const reqSvgs = require.context ('./images', true, /\.svg$/ )

const svgs = reqSvgs
  .keys ()
  .reduce ( ( images, path ) => {
    images[path] = reqSvgs ( path )
    return images
  }, {} )

---

SurviveJS gives a more generalized example of require.context here SurviveJS Webpack Dynamic Loading.

Stumbled onto this issue - I initially had the "Accepted answer", but i caused http request for each and every svg, which triggered a rate limit. So I ended up with a combination the accepted answer and what @karthik proposed - using a loader in the request.context

As of CRA 2.0 @svgr is included to import svg's as react components.

const reqSvgs = require.context('!@svgr/webpack!flag-icon-css/flags/4x3', true, /\.svg$/)

So here we combine an svg loader and require.context

const flagMap = reqSvgs.keys().reduce((images, path) => {
  const key = path.substring(path.lastIndexOf('/') + 1, path.lastIndexOf('.'))
  images[key] = reqSvgs(path).default
  return images
}, {})

Then we map all these into a json object so we can use key lookup

To render svg's in jsx:

const Flag = flagMap['dk']
return (
  <Flag />
)

And happy days, svgs included in bundle and no individual http requests

Instead of multiple SVG files you can use the single SVG sprite.

SVG sprite can be generated from a directory of SVG files using svg-sprite-generator:

svg-sprite-generate -d images -o images/sprite.svg

Then use it like this:

import React from 'react';
import { NavLink } from 'react-router-dom';
import sprite from './images/sprite.svg';

export default (props) => (
  <NavLink className="hex" activeClassName="active" to={'/hex/' + props.itemName}>
    <svg xmlns="http://www.w3.org/2000/svg" width="30" height="30">
      <use xlinkHref={`${sprite}#${props.itemName}`} />
    </svg>
  </NavLink>
)