主题：求幅度时提示的错误。

在分析“排名进退幅度”时，提示如图的错误，如何解决呢？谢谢！

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点击浏览该文件:成绩管理平台.zip

If e.DataRow.IsNull("科目")=False Then
    Select Case e.DataCol.name
        Case "届别","考试期数","年级","班别","科目"
            Dim dr As DataRow=e.DataRow
            Dim dt_StudentScore As DataTable=DataTables("StudentScore")
            Dim dt_pmsj As DataTable=DataTables("排名升降")
            Dim gjf As String=dt_pmsj.Compute("Max(" & dr("科目") & ")","[届别]='" & e.DataRow("届别") & "' And [考试期数] ='" & dr("考试期数") & "' And [年级]='" & dr("年级") & "' And [班别]='" & dr("班别") & "'")
            Dim djf As String=dt_pmsj.Compute("Min(" & dr("科目") & ")","[届别]='" & e.DataRow("届别") & "' And [考试期数] ='" & dr("考试期数") & "' And [年级]='" & dr("年级") & "' And [班别]='" & dr("班别") & "'")
            If gjf > "" AndAlso djf > "" Then
                e.DataRow("高幅度")=gjf.SubString(1,gjf.IndexOf("(")-1)
                e.DataRow("低幅度")=djf.SubString(1,djf.IndexOf("(")-1)
            End If
    End Select
End If

此主题相关图片如下：幅度.jpg

If e.DataRow.IsNull("科目")=False Then
    Select Case e.DataCol.name
        Case "届别","考试期数","年级","班别","科目"
            Dim dr As DataRow=e.DataRow
            Dim dt_StudentScore As DataTable=DataTables("StudentScore")
            Dim dt_pmsj As DataTable=DataTables("排名升降")
            Dim filter As String = "[届别]='" & e.DataRow("届别") & "' And [考试期数] ='" & dr("考试期数") & "' And [年级]='" & dr("年级") & "' And [班别]='" & dr("班别") & "' and " & dr("科目") & " like '↑%'"
            Dim dmax As DataRow = dt_pmsj.Find(filter, dr("科目") & " desc")
            Dim dmin As DataRow = dt_pmsj.Find(filter, dr("科目"))
           
            If dmax IsNot Nothing Then
                e.DataRow("高幅度")=dmax(dr("科目")).SubString(1,dmax(dr("科目")).IndexOf("(")-1)
                e.DataRow("低幅度")=dmin(dr("科目")).SubString(1,dmin(dr("科目")).IndexOf("(")-1)
                e.DataRow("高幅分")=dt_StudentScore.Compute("Max(" & dr("科目") & ")","[届别]='" & e.DataRow("届别") & "' And [考试期数]='" & e.DataRow("考试期数") & "' And [年级]='" & dr("年级") & "' And [班别]='" & dr("班别") & "' and 姓名 = '" & dmax("姓名") & "'")
                e.DataRow("低幅分")=dt_StudentScore.Compute("Min(" & dr("科目") & ")","[届别]='" & e.DataRow("届别") & "' And [考试期数]='" & e.DataRow("考试期数") & "' And [年级]='" & dr("年级") & "' And [班别]='" & dr("班别") & "' and 姓名 = '" & dmin("姓名") & "'")
                e.DataRow("高姓名") = dmax("姓名")
                e.DataRow("低姓名") = dmin("姓名")
            End If
    End Select
End If

谢谢！

但是此处的Dim filter As String = "[届别]='" & e.DataRow("届别") & "' And [考试期数] ='" & dr("考试期数") & "' And [年级]='" & dr("年级") & "' And [班别]='" & dr("班别") & "' and " & dr("科目") & " like '↑%'"有问题，比如一个是↑9，另一个是↑30.它获取的是↑9的值，即9，跟在“排名升降”中的显示的意思不一致。应该是要比较↑后面的数值大小，谢谢！

字符的比较就是这样的。要么不要在科目中放其它字符，增加一列放“↑”，科目改成整型

那能把字符型的数值转换成整型的数值吗？谢谢！

那就要排名升降表中作比较是不要字符了，直接用整型数值了

回复8楼，排序的时候没有办法转换类型