主题：[求助]成绩转换等级排除空值（缺考）代码

以下是把“成绩”（分数）根据一定的比例转换为 “等级”  的代码，由于各科成绩可能有“空”（缺考，可能每科都不同）的，怎样把“缺考”对象（科目）的等级填入“缺考”两字，并排除在等级计算对象之外，求补充代码

Dim ksmc As String = e.Form.Controls("ComboBox01").text
DataTables("学生成绩库").LoadFilter = "[考试名称] = '" & ksmc & "'"
DataTables("学生成绩库").Load()

Dim vals() As Double = {0.2,0.5,0.9}
Dim nms() As String = {"政治","语文","数学","英语"}
Dim cnt As Integer = DataTables("学生成绩库").DataRows.count
For Each nm As String In nms
Dim drs As List (of DataRow) = DataTables("学生成绩库").Select("", nm & " Desc")
Dim dn As String = nm & "等级"
For i As Integer = 0 To drs.count - 1
Dim v As Double = i /cnt
If v > vals(2) Then
drs(i)(dn) = "D"
ElseIf v > vals(1) Then
drs(i)(dn) = "C"
ElseIf v > vals(0) Then
drs(i)(dn) = "B"
Else
drs(i)(dn) = "A"
End If
Next
Next

可以了，谢谢！但是：

Dim cnt As Integer = DataTables("学生成绩库").DataRows.count

Dim v As Double = i /cnt

这里的 cnt  包括了 0分和缺考对象 

我想把这两种（0分和缺考对象）排除掉，剩下有分数的对象再按比例分等级，怎办？谢谢！

Dim vals() As Double = {0.2,0.5,0.9}

 For i As Integer = 0 To drs.count - 1
        Dim v As Double = i /cnt

If v > vals(2) Then
            drs(i)(dn) = "D"

下载信息  [文件大小：   下载次数： ]

点击浏览该文件:管理项目17.rar

如政治科：

13个 60分     7个A  6个B

12个 44分     4个B  8个C

12个 20分      5个C 7个D

谢谢