vb.net - CRUDOperations.vb 中的这行代码有什么作用？

Question

以下是 Microsoft Dynamics CRM 2011 SDK 中 CRUDOperations.vb 文件中的一些代码：

  ' Retrieve the account containing several of its attributes.
  Dim cols As New ColumnSet(New String() { "name", "address1_postalcode", "lastusedincampaign" })
  Dim retrievedAccount As Account = CType(_service.Retrieve("account", _accountId, cols), Account)
  Console.Write("retrieved, ")
  ' Update the postal code attribute.
  retrievedAccount.Address1_PostalCode = "98052"
  ' The address 2 postal code was set accidentally, so set it to null.
  retrievedAccount.Address2_PostalCode = Nothing

现在，如果我理解正确，以下行：

      Dim retrievedAccount As Account = CType(_service.Retrieve("account", _accountId, cols), Account)

好像真的什么都没做？

Answer 1

1. 它调用_service.Retrieve("account", _accountId, cols)
2. 它将返回值转换为 type Account。
3. 它将返回值存储在变量中retrievedAccount。

然后后面的几行修改了被引用的账户的属性retrievedAccount。