Question

我有一张excel表，我用这样的代码阅读

Public Async Function ReadRecordAsync() As Task(Of SellingList)
        Try
            Dim Sellings As New SellingList
            Await Conn.OpenAsync()
            Cmd = New OleDbCommand()
            Cmd.Connection = Conn
            Cmd.CommandText = "Select * from [Sheet1$]"
            Dim Reader = Await Cmd.ExecuteReaderAsync()
            While Reader.Read()
                If CheckEmptyReader(Reader) Then
                    MsgBox("First Empty Cell Index = " & Reader.Depth)
                    Exit While
                End If
                Dim x As New BuyableObject
                If Not Reader.IsDBNull(0) Then
                    x.Name = Reader.GetString(0)
                End If
                If Not Reader.IsDBNull(1) Then
                    x.SoldCount = GetIntegerValue(Reader(1).ToString)
                End If
                If Not Reader.IsDBNull(2) Then
                    x.SellingPrice = GetSingleValue(Reader(2).ToString)
                End If
                If Not Reader.IsDBNull(3) Then
                    x.OriginalPrice = GetSingleValue(Reader(3).ToString)
                End If
                x.UpdateCounts()
                If x.Name IsNot Nothing Then
                    Sellings.Add(x)
                End If
            End While
            Reader.Close()
            Conn.Close()
            Return Sellings
        Catch ex As Exception
            MsgBox(ex.ToString)
            Return New SellingList
        End Try
    End Function

我想在

获取当前行索引

MsgBox("First Empty Cell Index = " & Reader.Depth)

但它不起作用，总是返回0 并检查空读者：

Public Function CheckEmptyReader(reader As DbDataReader) As Boolean
        If IsDBNull(reader(0)) AndAlso IsDBNull(reader(1)) AndAlso IsDBNull(reader(2)) AndAlso IsDBNull(reader(3)) Then
            Return True
        Else
            Return False
        End If
    End Function

那么如何使用阅读器获取当前行索引？

Answer 1

我通过添加一个简单的计数器找到了一个简单的解决方案

Dim counter As Integer = 1 'start index
While Reader.Read()
   If CheckEmptyReader(Reader) Then
      MsgBox("First Empty Row Index = " & counter)
      Exit While
   End If
   'some code
   counter += 1
End While

在ADO.net中读取DbDataReader时如何获取当前行索引

1 个答案: