c# - 任务异步困惑

Question

我被要求将 WCF 服务调用从同步转换为异步，但该调用似乎仍在同步运行。我做错了什么？

这是我的服务契约(Contract)

[ServiceContract]
public interface ICredentialReplication
{
    /// <summary>
    /// Updates the store database with credential data
    /// </summary>
    /// <param name="credentials">the credential data to update</param>
    [OperationContract]
    Task ReplicateDataAsync(CredentialDataList credentials);

这是我的实现

/// <summary>
    /// Copy the credential data to the stores
    /// </summary>
    /// <param name="credentials">The credential data to copy</param>
    public async Task ReplicateDataAsync(CredentialDataList credentials)
    {
        var task = Task.Factory.StartNew(() => UpdateData(credentials));
        await task;  
    }

我已经在客户端中设置了“生成异步操作”标志来生成代理类，并使用以下代码调用服务(服务调用位于最后)

 foreach (var store in storedic)
            {
                // call the replication service for that store                    
                CredentialDataList credentialData = new CredentialDataList();
                List<CredentialData> credentialList = new List<CredentialData>();

                foreach (var payroll in store)
                {
                    CredentialData cred = this.ExtractCredentialData(data, pinData, payroll);
                    credentialList.Add(cred);                       
                }

                credentialData.CredentialList = credentialList.ToArray();
                credentialData.PermissionList = permDataList;
                credentialData.PermissionTypeList = permTypeDataList;   

                // then call the service
                this._client.ReplicateData(credentialData);     
            }               

我原以为在调试器中单步执行此循环应该立即返回，但它会等待服务调用完成后再返回。我错过了什么吗？

Answer 1

您似乎正在使用客户端 API 的同步版本，而不是异步版本:

this._client.ReplicateData(credentialData); 

而不是使用 async over sync anti-pattern ，我建议改用 API 的同步版本。

使用 WCF 来 generate a task based operation您可以等待:

var replicatedData =  await _client.ReplicateDataAsync();