主题：退出项目前判断，任何一个表的任意一行都不能为空，否则不能退出项目

 你对空行的定义是什么？

For Each t As Table In Tables
    For Each r As Row In t.rows
        Dim isNull As Boolean = True
        For Each c As Col In t.cols
            If r.IsNull(c.name) = False Then
                isNull = False
                Exit For
            End If
        Next
        If isNull Then
            msgbox(t.name & " " & r.index)

            e.Cancel = True
            Return
        End If
    Next
Next

Syscmd.Project.Exit()
vars("canClose") = True
basemainform.Close

关闭项目之前事件的代码是

If vars("canClose") = False Then
    e.Cancel = True
End If

改成

vars("canClose") = True
Syscmd.Project.Exit()