我能在VB.NET中实现IEnumerable函数的收益率返回吗？

Question

Possible Duplicate:
Yield In VB.NET

在C#中，当编写返回IEnumerble<>的函数时，可以使用yield return返回枚举的单个项，使用yield break;表示没有剩余项。做同样事情的VB.NET语法是什么？

来自NerdDinner代码的示例：

public IEnumerable<RuleViolation> GetRuleViolations() {

   if (String.IsNullOrEmpty(Title))
       yield return new RuleViolation("Title required","Title");

   if (String.IsNullOrEmpty(Description))
       yield return new RuleViolation("Description required","Description");

   if (String.IsNullOrEmpty(HostedBy))
       yield return new RuleViolation("HostedBy required", "HostedBy");

   if (String.IsNullOrEmpty(Address))
       yield return new RuleViolation("Address required", "Address");

   if (String.IsNullOrEmpty(Country))
       yield return new RuleViolation("Country required", "Country");

   if (String.IsNullOrEmpty(ContactPhone))
       yield return new RuleViolation("Phone# required", "ContactPhone");

   if (!PhoneValidator.IsValidNumber(ContactPhone, Country))
       yield return new RuleViolation("Phone# does not match country", "ContactPhone");

   yield break;
}

这个convert C# to VB.NET tool给出了一个“YieldStatement is unsupported”错误。

Answer 1

新的Async CTP包括对VB.NET中Yield的支持。

有关用法的信息，请参见Iterators in Visual Basic。