Angular 2-이미지 URL이 유효하거나 손상되었는지 확인

Angular 2-이미지 URL이 유효하거나 손상되었는지 확인

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API에서 많은 수의 이미지 URL을 가져 와서 Angular 2 웹 애플리케이션에 표시합니다. 일부 URL이 손상되어 웹 서버에 로컬로 저장된 기본 사진으로 바꾸고 싶습니다. 누구든지 URL을 테스트하고 상태 코드 404의 경우 깨진 이미지를 교체하는 방법에 대한 제안이 있습니까?

감사!

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error이미지 요소 의 이벤트를 수신합니다 .

<img [src]="someUrl" (error)="updateUrl($event)">

여기서 updateUrl(event) { ... }새 값을 this.someUrl.

플 런커 예

코드 만 체크인하려면 자바 스크립트를 사용하여 이미지가 있는지 확인 하기에서 설명한 방법을 사용할 수 있습니다.

@Directive({
  selector: 'img[default]',
  host: {
    '(error)':'updateUrl()',
    '[src]':'src'
   }
})
class DefaultImage {
  @Input() src:string;
  @Input() default:string;

  updateUrl() {
    this.src = this.default;
  }
}

Directive Plunker 예제

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onError이 방법으로 이벤트 를 사용 하여 invalid url또는 broken url.

• https://plnkr.co/edit/fD8zxd?p=preview

<img [src]="invalidPath" onError="this.src='images/angular.png'"/> 

이렇게하면 onError 이벤트를 사용하여 src에 img 경로를 직접 할당 할 수 있습니다.

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각도 4에 대한 나의 예

<img [src]="img" (error)="img.src = errorImg" #img>

1. 어디서 img-이미지 경로;
2. 오류-오류 방출
3. errorImg-기본 img 경로
4. #img-img 객체에 대한 링크

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나는 나를 위해 일한 매우 간단한 해결책을 찾았습니다. 이것은 404를 확인하지 않지만 .image 속성이있을 수있는 객체가 있습니다. 나는 이것이 그의 질문에 대한 답이 아니라는 것을 알고 있지만, 그것이 도움이되기를 바랍니다.

<img class="list-thumb-img" [attr.src]="item.image?.url ? item.image.url : 'assets/img/140-100.png'">

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base64 로딩 스피너를 사용합니다.

<img [src]="photoContainer.photo.url | secure" onError="this.src='data:image/svg+xml;base64,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'">

---

이것은 다중 이미지에 대한 대체 솔루션입니다. 이미지가 해결되면 기본적으로 ChangeDetector를 분리하여 이미지가 해결되면 VM 검사주기에서 CPU를 줄일 수 있습니다.

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';
    }





}

참고 URL : https://stackoverflow.com/questions/36429903/angular-2-check-if-image-url-is-valid-or-broken