Search code examples
javascriptreactjssvgdynamicimport

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


I have a component that takes in an :itemName and spits out an html bundle containing an image. The image is different for each bundle.

Here's what I have:

import React, { Component } from 'react';
import { NavLink } from 'react-router-dom';

import SVGInline from "react-svg-inline";

export default (props) => (
  <NavLink className="hex" activeClassName="active" to={'/hex/' + props.itemName}> {React.createElement(SVGInline, {svg: props.itemName})} </NavLink>
)

How could I make this component work?

I know that if I just imported all my images explicitly, I could just call my images like so...

import SVGInline from "react-svg-inline";
import SASSSVG from "./images/sass.svg";

<NavLink className="hex" activeClassName="active" to="/hex/sass"><SVGInline svg={ SASSSVG } /></NavLink>

This would work, but since I need to include ~60 svgs, it adds A LOT of excess code.

Also, I found in this question this code...

import * as IconID from './icons';

But that doesn't seem to work (it was part of the question, not the answer), and the answer was a bit too nonspecific to answer the question I'm asking.

I also found this question but again there's an answer (although unapproved) that possess more questions than it answers. So, after installing react-svg, I set up a test to see if the answer works like so...

import React, { Component } from 'react';
import ReactDOM from 'react-dom'
import { NavLink } from 'react-router-dom';
import ReactSVG from 'react-svg'

export default (props) => (
  <NavLink className="hex" activeClassName="active" to={'/hex/' + props.itemName}>
    <ReactSVG
      path={"images/" + props.itemName + ".svg"}
      callback={svg => console.log(svg)}
      className="example"
    />
  </NavLink>
)

But, just as the OP of that question was asking, the page can't find my svg even after copying my entire image folder into my build folder. I've also tried "./images/"

I feel like I'm just missing one last key piece of information and after searching for the past day, I was hoping someone could identify the piece I'm missing.


Solution

  • 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.