react.js Replace img src onerror

问题:

I have a react component that is the detail view from a list.

I am trying to replace the image with a default image if the image does not exist and there is a 404 error.

I would normally use the onerror method in the img tag but that doesn't seem to be working.

I am not sure how to do this with react.

Here is my component:

import React from 'react';
import {Link} from 'react-router';
import ContactStore from '../stores/ContactStore'
import ContactActions from '../actions/ContactActions';

class Contact extends React.Component {
  constructor(props) {
    super(props);
    this.state = ContactStore.getState();
    this.onChange = this.onChange.bind(this); 
 }

componentDidMount() {
  ContactStore.listen(this.onChange);
  ContactActions.getContact(this.props.params.id);
}

componentWillUnmount() {
  ContactStore.unlisten(this.onChange);
}

componentDidUpdate(prevProps) {
  if (prevProps.params.id !== this.props.params.id) {
    ContactActions.getContact(this.props.params.id);
  }
}

onChange(state) {
  this.setState(state);
}

render() {
  return (
    <div className='container'>
      <div className='list-group'>
        <div className='list-group-item animated fadeIn'>
          <h4>{this.state.contact.displayname}</h4>
          <img src={this.state.imageUrl} />
        </div>
      </div>
    </div>
  );
}
}

export default Contact;

回答1:

Since there is no perfect answer, I am posting the snippet I use. I am using reusable Image component that fallbacks to fallbackSrc.

Since the fallback image could fail again and trigger infinite loop of re-rendering, I added errored state.

import React, { Component } from 'react';
import PropTypes from 'prop-types';

class Image extends Component {
  constructor(props) {
    super(props);

    this.state = {
      src: props.src,
      errored: false,
    };
  }

  onError = () => {
    if (!this.state.errored) {
      this.setState({
        src: this.props.fallbackSrc,
        errored: true,
      });
    }
  }

  render() {
    const { src } = this.state;
    const {
      src: _1,
      fallbackSrc: _2,
      ...props
    } = this.props;

    return (
      <img
        src={src}
        onError={this.onError}
        {...props}
      />
    );
  }
}

Image.propTypes = {
  src: PropTypes.string,
  fallbackSrc: PropTypes.string,
};

回答2:

This works best for me

<img src={record.picture} onError={(e)=>{e.target.onerror = null; e.target.src="image_path_here"}}/>

回答3:

You can use uncontrolled component:

<img src={this.state.img} ref={img => this.img = img} onError={
    () => this.img.src = 'img/default.img'
}>

回答4:

You need just define onError handler than change the state which will trigger component render method and eventually component will re-render with placeholder.

Please, don't use jQuery and React together!

import React from 'react';
import {Link} from 'react-router';
import ContactStore from '../stores/ContactStore'
import ContactActions from '../actions/ContactActions';

class Contact extends React.Component {
  constructor(props) {
    super(props);
    this.state = ContactStore.getState();
    this.onChange = this.onChange.bind(this); 
 }

componentDidMount() {
  ContactStore.listen(this.onChange);
  ContactActions.getContact(this.props.params.id);
}

componentWillUnmount() {
  ContactStore.unlisten(this.onChange);
}

componentDidUpdate(prevProps) {
  if (prevProps.params.id !== this.props.params.id) {
    ContactActions.getContact(this.props.params.id);
  }
}

onChange(state) {
  this.setState(state);
}

onError() {
  this.setState({
    imageUrl: "img/default.png"
  })
}

render() {
  return (
    <div className='container'>
      <div className='list-group'>
        <div className='list-group-item animated fadeIn'>
          <h4>{this.state.contact.displayname}</h4>
          <img onError={this.onError.bind(this)} src={this.state.imageUrl} />
        </div>
      </div>
    </div>
  );
}

export default Contact;

回答5:

Arthur's answer will result in infinite callbacks if fallback image also fails.

To avoid that, first set a state in the constructor for imageLoadError as true :

constructor(props) {
    super(props);
    this.state = {
      imageLoadError: true,
    };
}

and then check for this state value in onError function to avoid infinite callbacks,

the code will look like this :-

<img
    src={"https://if_this_url_fails_go_to_onError"}
    onError={e => { 
        if(this.state.imageLoadError) { 
            this.setState({
                imageLoadError: false
            });
            e.target.src = 'fallbackImage.png';
        }
    }}
/>

回答6:

Ran into a similar problem and the best solution i could find was Georgii Oleinikov's answer. (Doesn't require making new imageLoadError state as suggested by Nitesh Ranjan in his answer)

onError={(e)=>{ if (e.target.src !== "image_path_here"){
                    e.target.onerror = null;
                     e.target.src="image_path_here";}
                }
           }

e.target.onerror = null is not needed (and doesn't really help) because the if condition is enough to prevent the infinite loop(if backup image fails to load as well).

So:

onError={(e)=>{ if (e.target.src !== "image_path_here"){
                 e.target.src="image_path_here";}
               }
         }

EDIT: The other way around is to set a flag outside the return brackets and check for the flag in the if statement. Code should look something like this:

render(){
 let errorflag=true;
 return(
            <img alt='' src={imageUrl} 
                    onError={(e)=>{ if (errorflag){ errorflag=false; e.target.src=url; } }} />
            );
} 

回答7:

I took @Skay's answer and created a reusable Image component. Posting in case it helps anyone:

import React, { PropTypes } from 'react';

const Image = ({src, fallbackSrc, ...other}) => {
    let element;
    const changeSrc = newSrc => {
        element.src = newSrc;
    };
    return (
        <img src={src} 
             onError={() => changeSrc(fallbackSrc)} 
             ref={el => element=el} 
             {...other} />
    );
};

Image.propTypes = {
    src: PropTypes.string,
    fallbackSrc: PropTypes.string
};
export default Image;

回答8:

import OriginalImage from '../../originalImg.png'
import ReplacementImage from '../../replaceImg.png'

<img
 src= OriginalImage
 alt="example"
 onError={(e) => {
    e.target.src = ReplacementImage //replacement image imported above
    e.target.style = 'padding: 8px; margin: 16px' // inline styles in html format
 }}
/>

this is what I'm currently using.

回答9:

@DepH's answer is nice, but it does produce and infinite loop if your error source also doesn't load. This helped me avoid the callback loop:

onError={(e)=>{ if (e.target.src !== "image_path_here") 
    { e.target.onerror = null; e.target.src="image_path_here"; } }}

回答10:

For those like me who also wanted to change the styles of the element and/or change the img source, just do something like this:

<img
  src={'original src url goes here'}
  alt="example"
  onError={(e) => {
     e.target.src = '/example/noimage.png' // some replacement image
     e.target.style = 'padding: 8px; margin: 16px' // inline styles in html format
  }}
/>

Hope it helps!

回答11:

Here's an answer using hooks:

import React, { useState } from 'react'

/**
 * Returns an object that can 
 * be spread onto an img tag
 * @param {String} img
 * @param {String} fallback
 * @returns {Object} { src: String, onError: Func }
*/
function useFallbackImg(img, fallback) {
  const [src, setImg] = useState(img)

  function onError(e) {
    console.log('Missing img', img, e)
    // React bails out of hook renders if the state
    // is the same as the previous state, otherwise
    // fallback erroring out would cause an infinite loop
    setImg(fallback)
  }

  return { src, onError }
}

/**
 * Usage <Image src='someUrl' fallback='fallbackUrl' alt='something' />
 */
function Image({src, fallback, ...rest}) {

  const imgProps = useFallbackImg(src, fallback)

  return <img {...imgProps} {...rest} />
}

And if you are want to handle the src prop changing, you can pass a key prop of the src. https://reactjs.org/blog/2018/06/07/you-probably-dont-need-derived-state.html#recommendation-fully-uncontrolled-component-with-a-key

<Image key='someUrl' src='someUrl' fallback='fallbackUrl' alt='...' />

The only extreme contrived edge case where using a key like this might fail is with sibling components. I think only one sibling node will render if they have the same key. To get around this you could probably wrap the Image in a <> Fragment.

<><Image key={srcProp} ... /></>
<><Image key={srcProp} ... /></>

回答12:

That's how I did it.

 class Pix extends React.Component{

          constructor(props){
            super(props);
           this.state={link: this.props.link};
           this.onError=this.onError.bind(this);
          }


          onError(){
              console.log("error: could not find picture");
              this.setState(function(){ return {link: "missing.png"}; });
             };

          render(){
          return <img onError={this.onError} src={this.state.link}/>;
          } 
    }

回答13:

You can use object if that's ok with your requirement. Something like below will work perfectly fine

<object data={expected_image} type="image/jpg">
  <img src={DEFAULT} alt="404" />
</object>

Check this answer for more details https://stackoverflow.com/a/29111371/1334182

回答14:

I wrote like this.

import React, { useState } from 'react';
import NoImageSVG from './noImage.svg';

const ImgWithFallback: React.FunctionComponent<{ src: string; alt: string; className: string }> = ({
  src,
  alt,
  className,
}) => {
  const [isUndefined, updateIsUndefined] = useState(false);

  const onError = () => {
    updateIsUndefined(true);
  };

  if (isUndefined) {
    return (
      <div className={className}>
        <NoImageSVG width='5rem' height='5rem' />
      </div>
    );
  }

  return <img src={src} alt={alt} className={className} onError={onError} />;
};

export default React.memo(ImgWithFallback, () => true);

回答15:

If anyone is using image src with require then onError doesn't work as -

<img src={require(`./../../assets/images/${props.imgName}.png`)} className="card-img" alt={props.name} />

then require throws an error, where I tried multiple ways and came to try and catch block solution as -

  let imgSrc;
  try {
    imgSrc = require(`./../../assets/images/${props.imgName}.png`);  
  } catch {
    imgSrc = require(`./../../assets/images/default.png`);
  }

and use as

<img src={imgSrc} className="card-img" alt={props.name} />

回答16:

this works for me .

{<img className="images"
    src={`/images/${student.src ? student.src : "noimage.png" }`} alt=  
{student.firstname} />} 

student is the name of my array and noimage the image, when there is no image is display.