.net - 为什么TextFieldParser.ReadField从字段中间删除连续的换行符？

Question

我正在使用VB.NET的TextFieldParser(Microsoft.VisualBasic.FileIO.TextFieldParser)读取分隔的文件。但是，当我尝试在该字段中包含连续换行符的字段中读取时，连续换行符会变成一条新换行。我希望保留连续的换行符，但是不确定如何保存。

这是我正在读取的一个示例文件，其中仅包含一个字段。引号是文件内容的一部分，并且包含三个换行符(包括第二行之后的两个连续换行符):

"This is line 1
This is line 2

This is line 4, which follows two consecutive newlines."

这是我用来解析和读取文件的代码:

Dim reader as New Microsoft.VisualBasic.FileIO.TextFieldParser(myFile, System.Text.Encoding.Default)
reader.TextFieldType = FileIO.FieldType.Delimited
reader.SetDelimiters(",")

Dim fields As String() = reader.ReadFields
Dim line As String = fields(0)

这是“line”变量的内容。请注意，现在只有两条换行符:

This is line 1
This is line 2
This is line 4, which follows two consecutive newlines.

我该怎么做才能保留连续的换行符？

Answer 1

首先，根据MSDN http://msdn.microsoft.com/en-us/library/microsoft.visualbasic.fileio.textfieldparser.readfields.aspx空行将被忽略:

If ReadFields encounters blank lines, they are skipped and the next non-blank line is returned.

我相信您需要做的是使用ReadLine http://msdn.microsoft.com/en-us/library/microsoft.visualbasic.fileio.textfieldparser.readline.aspx，然后遍历结果。

Using MyReader As New Microsoft.VisualBasic.FileIO.TextFieldParser("C:\ParserText.txt")
    MyReader.TextFieldType = Microsoft.VisualBasic.FileIO.FieldType.Delimited
    MyReader.Delimiters = New String() {","}
    Dim currentRow As String
    While Not MyReader.EndOfData
        Try
            currentRow = MyReader.ReadLine()
            'Manipulate line...
        Catch ex As Microsoft.VisualBasic.FileIO.MalformedLineException
            MsgBox("Line " & ex.Message & " is invalid.  Skipping")
        End Try
    End While
End Using