谢谢 Naga_Orochi 的指教.
终于和变量对上号了
Sub X6309X94AE5X00009_OnLButtonDown(ByVal Item, ByVal Flags, ByVal x, ByVal y)
Dim TagBool_1
Set TagBool_1 = HMIRuntime.Tags("TagBool_1")
TagBool_1.Read
Select Case TagBool_1.Value
Case 1
TagBool_1.Value =0
Case 0
TagBool_1.Value =1
Case Else
End Select
TagBool_1.Write
End Sub