1. 锁定Blob前必须检查Blob是否被另一个进程锁定。 在此之前，必须为Blob服务配置输入和输出文本框控件以进行Blob名称输入。

private async Task IsBlobLocked(CloudBlobContainer container, string blobName)
{
    CloudBlockBlob blockBlob = container.GetBlockBlobReference(blobName);
    try
    {
        AccessCondition accessCondition = new AccessCondition();
        accessCondition.LeaseId = null;
        await blockBlob.FetchAttributesAsync();
        return false;
    }
    catch (StorageException ex)
    {
        if (ex.RequestInformation.HttpStatusCode == 404)
            return false;
        if (ex.RequestInformation.ExtendedErrorInformation.ErrorCode == "LeaseIdMissing")
            return false;
        if (ex.RequestInformation.ExtendedErrorInformation.ErrorCode == "BlobAlreadyLeased")
            return true;
        throw ex;
    }
}

2. 使用以下代码段锁定Blob并获取租约ID。

private async Task LockBlob(CloudBlobContainer container, string blobName)
{
    CloudBlockBlob blockBlob = container.GetBlockBlobReference(blobName);
    AccessCondition accessCondition = new AccessCondition();
    accessCondition.LeaseId = null;
    string leaseId = await blockBlob.AcquireLeaseAsync(TimeSpan.FromSeconds(30), null, accessCondition, null);
    return leaseId;
}

3. 释放Blob的租约。

private async Task ReleaseBlob(CloudBlobContainer container, string blobName, string leaseId)
{
    CloudBlockBlob blockBlob = container.GetBlockBlobReference(blobName);
    AccessCondition accessCondition = new AccessCondition();
    accessCondition.LeaseId = leaseId;
    await blockBlob.ReleaseLeaseAsync(accessCondition);
}