主题：交叉查询分组统计

做个按钮执行代码

Dim dtb As New DataTableBuilder("统计")
dtb.AddDef("等级", Gettype(String), 32)
For Each v As String In DataTables("学生成绩").GetValues("班级")
    dtb.AddDef(v, Gettype(Double))
Next
dtb.Build()
Dim dt As Table = Tables("统计")
Dim dtsource As DataTable =  DataTables("学生成绩")
Dim ary1() As String = {"550分以上", "500-550"}
Dim ary2() As String = {750, 550}
Dim ary3() As String = {550, 500}
For i As Integer = 0 To ary1.length - 1
    Dim nr As Row = dt.AddNew
    nr("等级") = ary1(i)
    For j As Integer = 1 To dt.Cols.count-1
        nr(dt.Cols(j).name) = dtsource.Compute("count(班级)", "班级 = '" & dt.Cols(j).name & "' And 总分 > " & ary3(i) & " And 总分 <= " & ary2(i) & "")
    Next
Next
MainTable = dt

这样写

Dim ary2() As String = {750, 550, 500}
Dim ary3() As String = {550, 500, 0}