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如何获得总数或总结我的数据库访问权限

[英]How can I get the total or sum up my database access

我有这段代码可以过滤并显示数据库到datagridview

例如

score | scoretotal
25    | 30
20    | 40
25    | 25

现在,我如何才能获得测验的总数和“ scoretotal”的总数,或者我应该说,如何仅从datagridview显示的内容中获得总数?

Private Sub datagrid()
    Dim conn As New OleDbConnection
    Dim cmd As New OleDbCommand
    Dim da As New OleDbDataAdapter
    Dim dt As New DataTable
    Dim sSQL As String = String.Empty
    Try
        conn = New OleDbConnection(Get_Constring)
        conn.Open()
        cmd.Connection = conn
        cmd.CommandType = CommandType.Text
        sSQL = "SELECT  score as score, total as total FROM prelimquiz"
        sSQL = sSQL & " where username like '%" & Administrator.lblusername.Text & "%' and studentid like '%" & Me.Label25.Text & "%'"
        cmd.CommandText = sSQL
        da.SelectCommand = cmd
        da.Fill(dt)
        Me.DataGridView1.DataSource = dt
        If dt.Rows.Count = 0 Then
        End If
    Catch ex As Exception
        MsgBox(ErrorToString)
    Finally
        conn.Close()
    End Try
End Sub

任何意见和建议将不胜感激

通过linq:

 Dim dtAsEnum = dt.AsEnumerable
 Dim ScoreResult = dtAsEnum.Sum(Function(row) row.Field(Of Integer)("score"))
 Dim TotalResult = dtAsEnum.Sum(Function(row) row.Field(Of Integer)("total"))

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