javascript - @angular/火 AngularFireStorage getDownloadUrl()

Question

我正在尝试使用新的@angular/fire 5.1.0使用 AngularFireStorage 查看上传到 firebase 的图像。我曾经能够在 angularfire2 中使用 task.downloadURL()

“如果我错了请纠正我，但现在我必须使用 afStorage.getDownloadURL()请您协助我正确设置 imageUrl。

import { AngularFireStorage, AngularFireStorageReference, AngularFireUploadTask } from '@angular/fire/storage'
....
        downloadURL: Observable<string>; 
        imageUrl: string;
....

async onGetFromGallery(){
  try{ ....
    const imageData = await this.camera.getPicture(options);
    const image = 'data:image/jpeg;base64,' + imageData;
    const id = Math.random().toString(36).substring(2);
    const user = this.authenticatorService.getUser();
    this.ref = this.afStorage.ref(user.uid + '/images/categories/'+id);
    this.task = this.ref.putString(image, 'data_url');

    //--- Previously:angularfire2:
    // this.downloadURL = this.ref.getDownloadURL();
    // this.downloadURL.subscribe(url=> this.imageUrl=url);
    //--- now replaced by this.ref.getDownloadURL()...

    //My Attempt - unable to getDownloadUrl?
    this.task
    .snapshotChanges().toPromise().then(_ =>
       {
        this.ref.getDownloadURL().toPromise().then(res => {
          console.log('URL: ', res);
          this.imageUrl = res;
        });
      })

  } catch(e) {
    console.error(e);
    this.errorMessage = JSON.stringify(e);
  }
}

查看摘录:

<img [src]="imageUrl"  style="width:100%;">

package.json 摘录:

"@angular/compiler-cli": "5.2.11",
"@angular/fire": "^5.1.0",
"firebase": "^5.5.9",
"cordova-android": "~7.0.0",

谢谢。

Answer 1

代码中还有其他一些小的结构更改，而不仅仅是重命名方法。

查看 the example code in the official AngularFire2 docs在标题为“监控上传百分比”的部分下。具体来说，它们包括的示例上传功能:

uploadFile(event) {
    const file = event.target.files[0];
    const filePath = 'name-your-file-path-here';
    const fileRef = this.storage.ref(filePath);
    const task = this.storage.upload(filePath, file);

    // observe percentage changes
    this.uploadPercent = task.percentageChanges();

    // get notified when the download URL is available
    task.snapshotChanges().pipe(
        finalize(() => this.downloadURL = fileRef.getDownloadURL() )
     )
    .subscribe()
}

更具体地说，该功能的这一部分，即监听器......

// get notified when the download URL is available
task.snapshotChanges().pipe(
    finalize(() => this.imageUrl = fileRef.getDownloadURL() )
 )
.subscribe()

它会在上传完成并使用 URL 填充 this.downloadURL 变量时触发。您已经定义了 fileRef，在您的代码中它只是 ref，因此以下应该可以工作，但未经测试:

    // get notified when the download URL is available
    task.snapshotChanges().pipe(
        finalize(() => this.downloadURL = ref.getDownloadURL() )
     )
    .subscribe()