Angular 2 - Check if image url is valid or broken
JavascriptAngularJavascript Problem Overview
I am fetching a large number of image URLs from an API and display them in a angular 2 web application. Some of the URLs are broken and i want to replace them with a default picture that is stored locally on my webserver. Does anyone have a suggestion how to test the urls and in the case of status code 404 replace the broken image?
Thanks!
Javascript Solutions
Solution 1 - Javascript
Listen to the error
event of the image element:
<img [src]="someUrl" (error)="updateUrl($event)">
where updateUrl(event) { ... }
assigns a new value to this.someUrl
.
If you want to check in code only you can use the method explained in https://stackoverflow.com/questions/14651348/checking-if-image-does-exists-using-javascript
@Directive({
selector: 'img[default]',
host: {
'(error)':'updateUrl()',
'[src]':'src'
}
})
class DefaultImage {
@Input() src:string;
@Input() default:string;
updateUrl() {
this.src = this.default;
}
}
Solution 2 - Javascript
You can use onError
event this way to handle invalid url
or broken url
.
<img [src]="invalidPath" onError="this.src='images/angular.png'"/>
This way you can directly assign img path to src with onError event
Solution 3 - Javascript
My example on angular 4
<img [src]="img" (error)="img.src = errorImg" #img>
- Where img - path to image;
- error - error emmit
- errorImg - path to default img
- #img - link to img object
Solution 4 - Javascript
I use a base64 loading spinner:
<img [src]="photoContainer.photo.url | secure" onError="this.src='data:image/svg+xml;base64,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'">
Solution 5 - Javascript
I found a very simple solution that worked for me. This doesn't check for 404's however I had objects that possibly had and .image attribute. I know this isn't the answer to his question but hopefully it helps some one out there.
<img class="list-thumb-img" [attr.src]="item.image?.url ? item.image.url : 'assets/img/140-100.png'">
Solution 6 - Javascript
A perfect Angular 8 directive:
import {AfterViewInit, Directive, ElementRef, Input} from '@angular/core';
@Directive({
selector: '[appImage]'
})
export class ImageDirective implements AfterViewInit {
@Input() src;
constructor(private imageRef: ElementRef) {
}
ngAfterViewInit(): void {
const img = new Image();
img.onload = () => {
this.setImage(this.src);
};
img.onerror = () => {
// Set a placeholder image
this.setImage('assets/placeholder.png');
};
img.src = this.src;
}
private setImage(src: string) {
this.imageRef.nativeElement.setAttribute('src', src);
}
}
Now, HTML will be:
<img [src]="'/some/valid-image.png'" appImage>
Solution 7 - Javascript
If you want to change an image that is not loading or the source is broken... Angular 8, just have to change the src of this target for a default asset:
-
Component HTML
><... [src]="person.pictureUrl" (error)="pictNotLoading($event)" >
-
Component TS
>pictNotLoading(event) { event.target.src = 'assets/nopicture.png'; }
Solution 8 - Javascript
this is my solution for fallback on multi images. we basically detach the ChangeDetector once we resolve the image so we can reduce CPU on vm check cycles once image is resolved.
import {Component, ChangeDetectionStrategy, ChangeDetectorRef} from 'angular2/core';
import {AppStore} from "angular2-redux-util/dist/index";
@Component({
selector: 'logoCompany',
changeDetection: ChangeDetectionStrategy.Default,
template: `
<div style="padding-top: 7px" >
<span style="color: gainsboro; font-family: Roboto">{{getBusinessInfo('companyName')}}</span>
<!--<img style="width: 35px" class="img-circle" src="http://galaxy.example.me/Resources/Resellers/{{getBusinessInfo('businessId')}}/{{getBusinessInfo('fileName')}}" />-->
<img style="width: 35px" class="img-circle" [src]="getImageUrl()" (load)="onImageLoaded()" (error)="onImageError()" />
</div>
`
})
export class LogoCompany {
constructor(private cdr:ChangeDetectorRef) {
}
private imageRetries:number = 0;
private unsub;
private detach() {
this.cdr.detach();
}
private getImageUrl() {
var url = '';
switch (this.imageRetries){
case 0: {
url = 'http://galaxy.example.me/Resources/Resellers/' + this.getBusinessInfo('businessId') + '/Logo.jpg'
break;
}
case 1: {
url = 'http://galaxy.example.me/Resources/Resellers/' + this.getBusinessInfo('businessId') + '/Logo.png'
break;
}
default: {
url = 'assets/person.png'
break;
}
}
return url;
}
private onImageLoaded() {
this.detach();
}
private onImageError() {
this.imageRetries++;
}
private getBusinessInfo(field):string {
return '12345';
}
}
Solution 9 - Javascript
The event of error happen only if the url is not correct, if the url is correct but the file is not exists you can use in this code
javascript check if file exists on server:
(Note that the 404 is a number and not a string)
function doesFileExist(urlToFile) {
var xhr = new XMLHttpRequest();
xhr.open('HEAD', urlToFile, false);
xhr.send();
if (xhr.status == 404) {
return false;
} else {
return true;
}}
Solution 10 - Javascript
You can simply use a ternary operator for this use case. I am assuming that you are getting the responses from a remote server
<img src="{{ res.image ? res.image : onErrorFunction() }}"
If you don't want to have the image from server write the path in single quotes ''.
Here if the link is broken then it will go to onErrorFunction if it isn't broken the res.image will be loaded.