存在VB.Net Linq数据表

我想使用Linq而不是下面的函数：

Friend Function IsCollectionInTable2(ByVal apps As DataTable, ByVal collectionId As String) As Boolean
    For Each row As DataRow In apps.Rows
        If row("CollectionId").ToString = collectionId Then Return True
    Next
    Return False
End Function

我能做的最好的事情如下：

Friend Function IsCollectionInTable(ByVal apps As DataTable, ByVal collectionId As String) As Boolean
    Return (From row In apps.AsEnumerable()
             Where (row.Field(Of String)("CollectionId") = collectionId)
             Select row.Field(Of String)("CollectionId")).Count > 0
End Function

我想在上述函数中使用Exists或Any。性能可能是个问题，

怎么办（对不起，我的VB很差）

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我找到了一个似乎有效的解决方案：

Return (From row In apps.AsEnumerable()
        Where row.Field(Of String)("CollectionId") = collectionId).Any()

我希望这与以下速度一样快：

For Each row As DataRow In apps.Rows
If row("CollectionId").ToString = collectionId Then Return True
Next
Return False

---

比我的示例更好，但它仍然必须读取所有行。我想使用Exists或Any，以便它能尽快返回。

For Each row As DataRow In apps.Rows
If row("CollectionId").ToString = collectionId Then Return True
Next
Return False