主题：MainTable = Tables("合同") 不激活MainTableChanging

1、你条件本身就有问题。如果能使用 Tables("合同") ，那么肯定不满足 DataTables.Contains(e.NewTableName)=False

2、你可以在事件加入msgbox(123)看是否触发

3、只有表格切换的时候才会触发事件，如果你现在就在合同表，肯定不触发。

全局代码

Property MainTable As String

Get

Return foxtable.MainTable.name

End Get

Set  (ByVal value As String)

If Tables.contains(value) Then
    foxtable.MainTable = Tables(value)
Else
    msgbox("不存在表[" & value & "]")
End If
End Set
End Property

调用代码

MainTable = "表C"

mark，全局代码

Public Class myTableCollection
Public Sub new
End Sub

Default Public readonly Property Item(tname As String) As Table
Get
If Foxtable.Tables.Contains(tname) Then
    Return Foxtable.Tables(tname)
Else
    msgbox("测试,不存在表【" & tname & "】")
    Return Nothing
End If
End Get
End Property

End Class

Public mytables = new myTableCollection

readonly Property Tables As myTableCollection
Get
Return mytables
End Get
End Property

测试电脑代码

msgbox(Tables.Gettype.name)
msgbox(Tables("表B").name)
MainTable = Tables("表B")
MainTable = Tables("表abc")

完整点改成这样，基本就没问题了。

Public Class myTableCollection

Public Sub new
End Sub

Public Function GetEnumerator() As System.Collections.Generic.IEnumerator(Of Table)
Return foxtable.Tables.GetEnumerator
End Function

readonly Property Tables As myTableCollection
Get
Return mytables
End Get
End Property

请认认真真看7楼代码，以及调用代码。

Public Class myTableCollection

Public Sub new
End Sub

Public Function GetEnumerator() As System.Collections.Generic.IEnumerator(Of Table)
Return foxtable.Tables.GetEnumerator
End Function

readonly Property Tables As myTableCollection
Get
Return mytables
End Get
End Property

-----------------------

msgbox(Tables.Gettype.name)
msgbox(Tables("表B").name)
MainTable = Tables("表B")
MainTable = Tables("表abc")