如果您想使用restapi来实现这一点，我们可以使用以下代码。我和 Postman 一起测试。

private const string AppendUrl = "https://{datalakeName}.azuredatalakestore.net/webhdfs/v1/{filepath}?append=true&op=APPEND&api-version=2016-11-01"
var token = "eyJ0eX.....";
using (var client = new HttpClient())
{
     client.DefaultRequestHeaders.Authorization = new AuthenticationHeaderValue("Bearer", token);
     var result = client.GetAsync(url).Result;
     var data = result.Content.ReadAsStringAsync().Result;
}

我们还可以使用azure microsoft.azure.management.datalake.store来实现这一点。如何获得应用程序id和secretkey你可以参考官方文件。获取访问datalake的权限的更详细步骤您可以参考另一个so线程。

var applicationId = "application Id";
var secretKey = "secretKey";
var tenantId = "tenant id";
var adlsAccountName = "datalake account name";
var creds = ApplicationTokenProvider.LoginSilentAsync(tenantId, applicationId, secretKey).Result;
var adlsFileSystemClient = new DataLakeStoreFileSystemManagementClient(creds,clientTimeoutInMinutes:60);
var stream = File.OpenRead(@"C:\tom\testtext.txt");
var test = adlsFileSystemClient.FileSystem.AppendWithHttpMessagesAsync(adlsAccountName, "test/abc.txt", stream).Result;

Package ：

<?xml version="1.0" encoding="utf-8"?>
<packages>
  <package id="Microsoft.Azure.Management.DataLake.Store" version="2.3.0-preview" targetFramework="net452" />
  <package id="Microsoft.Azure.Management.DataLake.StoreUploader" version="1.0.0-preview" targetFramework="net452" />
  <package id="Microsoft.IdentityModel.Clients.ActiveDirectory" version="3.13.8" targetFramework="net452" />
  <package id="Microsoft.Rest.ClientRuntime" version="2.3.9" targetFramework="net452" />
  <package id="Microsoft.Rest.ClientRuntime.Azure" version="3.3.9" targetFramework="net452" />
  <package id="Microsoft.Rest.ClientRuntime.Azure.Authentication" version="2.2.0-preview" targetFramework="net452" />
  <package id="Newtonsoft.Json" version="9.0.2-beta1" targetFramework="net452" />
</packages>