VB.Net CSV檔案處理類

Imports System.Data.OleDbImports System.DataImports System.TextImports System.IO''' <summary>''' CSV檔案讀寫''' </summary>''' <remarks></remarks>Public NotInheritable Class Csv    Public Shared Encoding As Encoding = Encoding.GetEncoding("GB2312")    Private Shared ConnectionString As String = "Provider=Microsoft.Jet.OLEDB.4.0;Data Source={0};Extended Properties='Text;{1}'"    Public Shared Function OpenCsvFile(Optional ByVal Filter As String = "CSV (逗號分隔)(*.csv)|*.csv") As String        Dim Path As String = String.Empty        Using Open As New OpenFileDialog            Open.Multiselect = False            Open.Filter = Filter            Open.InitialDirectory = Application.StartupPath            If Open.ShowDialog = 1 Then Path = Open.FileName        End Using        Return Path    End Function#Region "Read"    ''' <summary>    ''' 讀取CSV檔案    ''' </summary>    ''' <param name="FilePath">CSV檔案路徑</param>    ''' <param name="HDR">是否有欄位標題</param>    ''' <returns>返回的DataTable</returns>    ''' <remarks></remarks>    Public Shared Function Read(ByVal FilePath As String, Optional ByVal HDR As Boolean = True) As DataTable        Dim con As New OleDbConnection(String.Format(ConnectionString, Path.GetDirectoryName(FilePath), IIf(HDR, String.Empty, "HDR=no;")))        Dim Name As String = Path.GetFileNameWithoutExtension(FilePath)        Dim dt As New DataTable(Name)        Using da As New OleDbDataAdapter(String.Format("select * from [{0}.csv]", Name), con)            Try                da.Fill(dt)            Catch ex As OleDbException                MsgBox(ex.Message)            End Try        End Using        con.Dispose()        Return dt    End Function    ''' <summary>    ''' 讀取CSV字串    ''' </summary>    ''' <param name="CsvString">Csv格式字串</param>    ''' <returns>返回的DataTable</returns>    ''' <remarks></remarks>    Public Shared Function StringRead(ByVal CsvString As String) As DataTable        Dim dt As New DataTable        On Error Resume Next        Dim str() As String = Split(CsvString, vbCrLf)        Dim cs() As String = Split(str(0), ","c)        For i = 0 To cs.Length - 1            dt.Columns.Add(cs(i), GetType(String))        Next        For i = 1 To str.Length - 1            Dim Cells() As String = Split(str(i), ","c)            If Cells.Length <> dt.Columns.Count Then                Continue For            Else                dt.Rows.Add(Split(str(i), ","c))            End If        Next        'dt.PrimaryKey = New DataColumn() {dt.Columns(0)}        Return dt    End Function    ''' <summary>    ''' 讀取CSV檔案    ''' </summary>    ''' <param name="FilePath">CSV檔案路徑</param>    ''' <returns>返回的DataTable</returns>    ''' <remarks></remarks>    Public Shared Function Read2(ByVal FilePath As String) As DataTable        Using sr As New StreamReader(FilePath, Encoding)            Return StringRead(sr.ReadToEnd)            sr.Close()        End Using    End Function#End Region#Region "Write"    ''' <summary>    ''' 儲存DataTable到CSV檔案    ''' </summary>    ''' <param name="Path">CSV檔案路徑</param>    ''' <param name="Table">要儲存的DataTable</param>    ''' <remarks></remarks>    Public Shared Sub Save(ByVal Path As String, ByVal Table As DataTable)        Using sw As New StreamWriter(Path, False, Encoding)            sw.Write(CsvString(Table)) : sw.Flush() : sw.Close()        End Using    End Sub    ''' <summary>    ''' 儲存DataRow數組到CSV檔案    ''' </summary>    ''' <param name="Path">CSV檔案路徑</param>    ''' <param name="Rows">要儲存的DataRow數組</param>    ''' <remarks></remarks>    Public Shared Sub Save(ByVal Path As String, ByVal Rows() As DataRow)        Using sw As New StreamWriter(Path, False, Encoding)            sw.Write(CsvString(Rows)) : sw.Flush() : sw.Close()        End Using    End Sub    ''' <summary>    ''' 儲存字串到CSV檔案    ''' </summary>    ''' <param name="Path">CSV檔案路徑</param>    ''' <param name="s">要儲存字串</param>    ''' <remarks></remarks>    Public Shared Sub Save(ByVal Path As String, ByVal s As String)        Using sw As New StreamWriter(Path, False, Encoding)            sw.Write(s) : sw.Flush() : sw.Close()        End Using    End Sub#End Region#Region "Utils"    Private Shared Function CsvString(ByVal Table As DataTable) As StringBuilder        Dim str As New StringBuilder        If Table.Columns.Count = 0 Then Return str        For Each c As DataColumn In Table.Columns            str.Append(CellString(c.ColumnName) & ",")        Next        str.Remove(str.Length - 1, 1).Append(vbCrLf)        For Each r As DataRow In Table.Rows            str.AppendLine(RowString(r))        Next        Return str    End Function    Private Shared Function CsvString(ByVal Rows() As DataRow) As StringBuilder        Dim str As New StringBuilder        For Each r As DataRow In Rows            str.AppendLine(RowString(r))        Next        Return str    End Function    Private Shared Function RowString(ByVal Row As DataRow) As String        Dim str As New StringBuilder        For Each s In Row.ItemArray            str.Append(CellString(s.ToString) & ",")        Next        Return str.Remove(str.Length - 1, 1).ToString    End Function    ''' <summary>    ''' CSV字串轉換    ''' </summary>    ''' <param name="s">要轉換的字串</param>    ''' <returns>返迴轉換後的字串</returns>    ''' <remarks></remarks>    Public Shared Function CellString(ByVal s As String) As String        If String.IsNullOrWhiteSpace(s) Then Return String.Empty        Dim str As New StringBuilder(s)        If IsAddChr34(s) Then            str.Replace(Chr(34), Chr(34) & Chr(34))            str.Insert(0, Chr(34))            str.Append(Chr(34))        End If        Return str.ToString    End Function    Private Shared Function IsAddChr34(ByVal s As String) As Boolean        Return s.IndexOf(Chr(10)) <> -1 OrElse s.IndexOf(Chr(13)) <> -1 _        OrElse s.IndexOf(Chr(34)) <> -1 OrElse s.IndexOf(Chr(44)) <> -1    End Function#End RegionEnd Class

http://knab.ws/blog/index.php?/archives/10-CSV-file-parser-and-writer-in-C-Part-2.html

http://blog.bossma.cn/csharp/a-fast-csv-reader-tool-user-csharp/