本文整理匯總了VB.NET中System.Data.DataTableReader.GetChars方法的典型用法代碼示例。如果您正苦於以下問題：VB.NET DataTableReader.GetChars方法的具體用法？VB.NET DataTableReader.GetChars怎麽用？VB.NET DataTableReader.GetChars使用的例子？那麽, 這裏精選的方法代碼示例或許可以為您提供幫助。
在下文中一共展示了DataTableReader.GetChars方法的1個代碼示例，這些例子默認根據受歡迎程度排序。您可以為喜歡或者感覺有用的代碼點讚，您的評價將有助於係統推薦出更棒的VB.NET代碼示例。
示例1: Module1
' 導入命名空間
Imports System.Data
Imports System.IO
Module Module1
Private Sub TestGetChars( _
ByVal reader As DataTableReader, ByVal bufferSize As Integer)
' The filename is in column 0, and the contents are in column 1.
Const FILENAME_COLUMN As Integer = 0
Const DATA_COLUMN As Integer = 1
Dim buffer() As Char
Dim offset As Integer
Dim charsRead As Integer
Dim fileName As String
Dim currentBufferSize As Integer
While reader.Read
' Reinitialize the buffer size and the buffer itself.
currentBufferSize = bufferSize
ReDim buffer(bufferSize - 1)
' For each row, write the data to the specified file.
' First, verify that the FileName column isn't null.
If Not reader.IsDBNull(FILENAME_COLUMN) Then
' Get the file name, and create a file with
' the supplied name.
fileName = reader.GetString(FILENAME_COLUMN)
' Start at the beginning.
offset = 0
Using outputStream As New StreamWriter(fileName, False)
Try
' Loop through all the characters in the input field,
' incrementing the offset for the next time. If this
' pass through the loop reads characters, write them to
' the output stream.
Do
charsRead = Cint(reader.GetChars(DATA_COLUMN, offset, _
buffer, 0, bufferSize))
If charsRead > 0 Then
outputStream.Write(buffer, 0, charsRead)
offset += charsRead
End If
Loop While charsRead > 0
Catch ex As Exception
Console.WriteLine(fileName & ": " & ex.Message)
End Try
End Using
End If
End While
Console.WriteLine("Press Enter key to finish.")
Console.ReadLine()
End Sub
Sub Main()
Dim table As New DataTable
table.Columns.Add("FileName", GetType(System.String))
table.Columns.Add("Data", GetType(System.Char()))
table.Rows.Add("File1.txt", "0123456789ABCDEF".ToCharArray)
table.Rows.Add("File2.txt", "0123456789ABCDEF".ToCharArray)
Dim reader As New DataTableReader(table)
TestGetChars(reader, 7)
End Sub
End Module