Sub OnClick(Byval Item)                 

Dim MSFGridFree,listFree,TimeInterval,comboxS,DaySelectSTA,HourST,HourED,DaySelectEDA,optasc,SelHourA

Dim STARTime,ENDtime'开始时间和结束时间变量

Set MSFGridFree = ScreenItems("MSFGridHour")

Set listFree=ScreenItems("ListParaF")

Set TimeInterval = ScreenItems("SelHourF")

Set comboxS = ScreenItems("DataTypeHour")

Set DaySelectSTA = ScreenItems("DaySelectSF")

Set HourST = ScreenItems("StartHourF")

Set DaySelectEDA = ScreenItems("DaySelectEF")

Set HourED = ScreenItems("EndHourF")

Set optasc = ScreenItems("AscOPThour")

    On Error Resume Next

    MSFGridFree.Clear

    Select Case Trim(comboxS.text)

        Case "平均值"

            FieldName = "PAVG"

        Case "最大值"

            FieldName = "PMAX"

        Case "最小值"

            FieldName = "PMIN"

        Case "采样值"

            FieldName = "PSAM"

    End Select

STARTime = DaySelectSTA.Value & " " & HourST.Text & ":00:00"'查询的开始时间

ENDtime = DaySelectEDA.Value & " " & HourED.Text & ":00:00"'查询的结束时间

If DateDiff("h",Now,ENDtime) > 0 Then

MsgBox "结束时间不能大于当前时间！",65,"提示"

Exit Sub

End If

If DateDiff("h",STARTime,ENDtime) <= 0 Then

MsgBox "结束时间不能小于开始时间！",65,"提示"

Exit Sub

End If

'STARTime = DateAdd("d",-1,STARTime)

'ENDtime = DateAdd("h",-1,ENDtime)'查询的结束时间减去一小时

'STARTime = Year(STARTime) & "-" & Month(STARTime) & "-" & Day(STARTime) & " " & Hour(STARTime) & ":" & Minute(STARTime) & ":" & Second(STARTime)

'ENDtime = Year(ENDtime) & "-" & Month(ENDtime) & "-" & Day(ENDtime) & " " & Hour(ENDtime) & ":" & Minute(ENDtime) & ":" & Second(ENDtime)

hmiruntime.Trace DateDiff("h",STARTime,ENDtime) & "y与开始"

HMIRuntime.Trace DateDiff("h",Now,ENDtime) & "y与现在"

HMIRuntime.Trace STARTime & vbCrLf & ENDtime & vbCrLf

这个是原来报表的语句，我现在想改成只显示一个电量的累计值，而在查询区间内每小时显示电量的差值，最后应如何修改呢？并且将差值显示在柱状图中，请各位大神帮忙看看