首先，如果你只是想给下一行的引用赋一个不同的列表，不要创建一个New的客户列表。这样做有点愚蠢。可以这样做：

Dim customers As List(Of Customer) = dataAccess.GetCustomers()

然后，对于循环，你需要一个简单的“For”循环，而不是for each。不要忘记在列表结束前停止：

For i As Integer = 500 To Customers.Count -1 
    'do something with Customers(i) here
Next i

如果您使用的是Visual Studio 2008，也可以这样编写：

For each item As Customer in  Customers.Skip(500)
   'Do something with "item" here
Next

请尝试以下操作

For Each current In customers
    ' Do something here 
    Console.WriteLine(current.Name)
Next

类似这样的东西：-

Dim customers as New List(Of Customer)

Customers=dataAcess.GetCustomers()

For Each customer AS Customer in  Customers
   '' // do something with the customer object
Next

编辑

听起来你想从N个项目中选择500个，或者下500个。你可以使用LINQ扩展方法.Take和/或.Skip来实现这一点。然后使用ToList创建你的列表。例如：-

Dim customers as List(Of Customer)
customers = dataAccess.GetCustomers().Skip(500).Take(500).ToList()

如果你只想通过客户进行枚举，那么你可以省去ToList（）。

“这将从500开始，一直进行到结束......”

for start as integer = 500 to Customers.Count

'process customer....
customer = Customers(start)

Next

要迭代整个列表：

for each cust as Customer in Customers

Next

需要注意的是.... VB不区分大小写，您的示例代码似乎使用了小写和大写客户

Dim start as Integer
Dim customers as New List(Of Customers)

Customers = dataAcess.GetCustomers()

For i as Integer = start to Customers.count Step 500
    Debug.Print Customers(i).someProperty
    Do something here
Next i

我认为您需要使用客户索引和500s中的步骤。这将只处理客户（开始）、客户（开始+500）、客户（开始+1000）等，而不是所有客户。这是您的意图吗？

我不太清楚你想干什么，但也许你可以试试这个：

Dim count As Integer = 0
Const MAX_CUSTOMERS As Integer = 500
Dim customers As List(Of Customers) = dataAcess.GetCustomers()

For Each c As Customer In customers
    'do stuff here'
    c.Name = "Billy"
    count+=1

    If count = MAX_CUSTOMERS Then Exit For
Next

这并不优雅，但它是有意义的，它会工作。

显然，这里并不缺少各种各样的对象。我不认识您的“DataAcess”对象类型，但是如果您可以将该表作为Recordset（即SQL表）拉入，那么请尝试这样做。（完成后不要忘记返回记录集）

Option Explicit

Dim Customers As Recordset
Set Customers=currentdb.openrecordset("???")

While Customers.EOF=False
   'do stuff here using the recordset object
   'i.e. Customers.Fields("Name")="Billy"
   Customers.MoveNext
Wend

您可以尝试：

For i As Integer = 500 To (customers.Count -1)
        ''do something
    Next

或者

For i As Integer = 0 To (customers.Count - 1) step 500
        ''do something
    Next