如何使用 angular return 服务功能数据到组件？

Question

我有一个具有 s3 存储桶上传功能的服务，我可以将图像上传到 s3。但我无法 return 从服务层到组件的信息。

你能帮我解决这个问题吗？

Service.ts:

async uploadFile(file, path): Promise<any> {
    const contentType = file.type;
    const bucket = new S3(
      {
        accessKeyId: 'My Access Key',
        secretAccessKey: 'My Secret Key',
        region: 'eu-west-1'
      }
    );
    const params = {
      Bucket: 'sangram-adaptive',
      Key: path + '/' + file.name,
      Body: file
    };
    
    await bucket.upload(params, function (err, data) {
      if (err) {
        console.log('Error', err);
        return err;
      }

      if (data) {
        console.log('Successfully uploaded', data); // i am getting result after upload
        this.fileData = data;
        return this.fileData; 
      }
    });
  }

Component.ts

async upload() {
    const file = this.selectedFiles.item(0);
    let data = await this.s3FileuploadService.uploadFile(file, 'tenant_files/' + Constants.TENANT + '/blogs');
    console.log(data); // Here it's showing undefined
  }

Answer 1

bucket.uploadreturn函数是哪个类型的？

你不应该这样称呼它：

await bucket.upload(...)

如果它return是一个承诺？

Answer 2

考虑将 uploadFile 修改为 return Promise，如下所示：

uploadFile(file, path): Promise<any> {
  const contentType = file.type;
  const bucket = new S3(
    {
      accessKeyId: 'My Access Key',
      secretAccessKey: 'My Secret Key',
      region: 'eu-west-1'
    }
  );
  const params = {
    Bucket: 'sangram-adaptive',
    Key: path + '/' + file.name,
    Body: file
  };

  return new Promise((resolve, reject) => {
    bucket.upload(params, (err, data) => err ? reject(err) : resolve(data))    
  })
}

如何使用 angular return 服务功能数据到组件？

how to return service function data to component using angular?

javascript

amazon-s3

typescript

aws-sdk

angular