c# - Activity 函数应返回 IEnumerable<IListBlobItem>

Question

我有一个事件函数，它应该返回 IEnumerable<IListBlobItem>如下:

[FunctionName("process_file_GetBlobList")]
public static IEnumerable<IListBlobItem> GetBlobList([ActivityTrigger] string name, ILogger log)
{
    string storageConnectionString = @"connstring";
    CloudStorageAccount storageAccount = CloudStorageAccount.Parse(storageConnectionString);
    CloudBlobClient blobClient = storageAccount.CreateCloudBlobClient();
    CloudBlobContainer container = blobClient.GetContainerReference("container");
    IEnumerable<IListBlobItem> blobs = new IListBlobItem[0];

    foreach (IListBlobItem blobItem in container.ListBlobs())
    {
        if (blobItem is CloudBlobDirectory)
        {
            CloudBlobDirectory directory = (CloudBlobDirectory)blobItem;
            blobs = directory.ListBlobs(true);
        }
    }

    return blobs;
}

在我的 Orchestrator 中，我按如下方式调用此事件函数:

 IEnumerable<IListBlobItem> blobs = await context.CallActivityAsync<IEnumerable<IListBlobItem>>("process_file_GetBlobList", null);

通过调试，我没有收到错误消息，但在运行时我收到此消息:

failed: Could not create an instance of type Microsoft.Azure.Storage.Blob.IListBlobItem. Type is an interface or abstract class and cannot be instantiated. Path '[0].StreamWriteSizeInBytes'

有任何想法吗，我如何通过 CallActivityAsync 调用我的事件函数？

Answer 1

将其更改为列表并查看，

  List<ListBlobItem> blobs = await context.CallActivityAsync<List<ListBlobItem>>("process_file_GetBlobList", null);

但是，您可以通过将 blob 更改为 var 类型来修复上述错误。