How do I dynamically import images in React?

问题

Have seen a couple of answers online but there are no clear explanations and the solutions don't work. So this is what I am trying to do:

I have a folder of MANY images (thousands) - currently it is saved under src/assets/images folder
Given a list of images for example as input, I want to render these images dynamically. And not import all because it would be impossible given the insane number of images

This is my current way of implementing it (which does not work):

// for example
const imageList = ['img1', 'img2', 'img3' /*...so on */]

const getImagePath = (image) => {
  return `../assets/images/${image}.jpg`
}

function ImagesPage() {
  return (
    <>
      <p>Below should show a list of images</p>
      {imageList.map((img) => {
        return <img src={require(getImagePath(img))} />
      })}
    </>
  )
}

From what I read online, this has something to do with the way webpack works, and this will only work if the exact string path is input into the require:

// This works:
<img src={require('../assets/images/img1.jpg')} />

// But all these will not work:
<img src={require(getImagePath(img))} />

const img = 'img1.jpg'
<img src={require(`../assets/images/${img}`)} />

Any idea how I can get this dynamic importing of images to work in the scenario I described above? I think this post will be quite helpful to the others searching for an answer too.

回答1:

TLDR;

// All of these works

const fileNameExt = 'foo.jpg'
<img src={require('../images/' + fileNameExt)} />
<img src={require(`../images/${fileNameExt}`)} />

const fileName = 'foo'
<img src={require('../images/' + fileName + '.jpg')} />
<img src={require(`../images/${fileName}.jpg`)} />

// These does not work:

const myPathVariable1 = '../images/' + 'foo' + '.jpg'
<img src={require(myPathVariable1)} />

const myPathVariable2 = '../images/' + 'foo.jpg'
<img src={require(myPathVariable2)} />

You can require dynamically with expression.

File names:

const imageList = ["img1", "img2", "img3", ... ]

And to render at UI (add directory path and the extension inside require):

{
  imageList.map(img => {
    return <img src={require("../assets/images/" + img + ".jpg")} />
  })
}

Why it works?:

Webpack can understand this expression, by generating context about directory and extension, and can load all the matching modules.

回答2:

Update your getImagePath function to return an img element.

const getImage = (image) => {
   return <img src={require(`../assets/images/${image}.jpg`)} />
}

Then your map function would look like this:

imageList.map((img) => {
   return getImage(img);
});

回答3:

  // for example
const imageList = ['img1', 'img2', 'img3' /*...so on */]

const getImagePath = (image) => {
  return `../assets/images/${image}.jpg`
}

function ImagesPage() {
  return (
    <>
      <p>Below should show a list of images</p>
      {imageList.map((img) => {
        return <img src={require(getImagePath(img)).default} />
      })}
    </>
  )
}

If you are using "create react app", adding .default after require works fine, it sets all images dynamically from local image folder.

回答4:

Adding .default will do the trick

<img src={require(`../../folder-path/${dynamic-filename}.png`).default} />

来源：https://stackoverflow.com/questions/62192049/how-do-i-dynamically-import-images-in-react

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javascript

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dynamic-import