batch-delete-azure-blob-folder.cs

// dotnet add package Azure.Storage.Blobs
// dotnet add package Azure.Storage.Blobs.Batch
using Azure.Storage.Blobs;
using Azure.Storage.Blobs.Models;
using Azure.Storage.Blobs.Specialized;


// Get a connection string to our Azure Storage account.
const string connectionString = "";
const string containerName = "";
const string prefix = "";

// < 256
const int MAX_BATCH = 250;


// Get a reference to a container named "sample-container" and then create it
BlobServiceClient service = new BlobServiceClient(connectionString);
BlobContainerClient containerClinet = service.GetBlobContainerClient(containerName);
BlobBatchClient batch = service.GetBlobBatchClient();
var blobItems = containerClinet.GetBlobsAsync(prefix: prefix);

var counter = 0;
var list = new List<string>();
Console.WriteLine("batch delete!");
await foreach (var blobItem in blobItems)
{
    list.Add(blobItem.Name);
    Console.WriteLine(blobItem.Name.Substring(prefix.Length));
    if (list.Count >= MAX_BATCH)
    {
        var task = list;
        list = new List<string>();
        await BatchDelete(task);
    };
}
await BatchDelete(list);

async Task BatchDelete(List<string> items)
{
    Console.WriteLine("task start");
    await batch.DeleteBlobsAsync(items.Select(i => new Uri(containerClinet.Uri + "/" + i)));
    counter += items.Count;
    Console.WriteLine($"${items.Count} tasks done, total ${counter}");
}