TextFieldParser.ReadFields Method
Assembly: Microsoft.VisualBasic (in microsoft.visualbasic.dll)
For more detailed information, see the Visual Basic topic TextFieldParser.ReadFields Method.
In order to allow users to parse text files in multiple formats, the ReadFields method examines the values of TextFieldType, Delimiters, and FieldWidths, if they are specified, each time it is called. Users need to correctly configure the TextFieldType and FieldWidths or Delimiters properties, as appropriate. If TextFieldType is set to Delimited, and Delimiters is not set, or if TextFieldType is set to FixedWidth and FieldWidths, an exception is thrown.
If ReadFields encounters blank lines, they are skipped and the next non-blank line is returned.
The following table lists examples of tasks involving the ReadFields method.
| To | See |
|---|---|
| Read from a delimited file | How to: Read From a Comma-Delimited Text File in Visual Basic |
| Read from a fixed-width file |
This example uses the ReadFields method to read from the file ParserText.txt and write the fields to Testfile.txt.
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.ReadFields() For Each currentField As String In currentRow My.Computer.FileSystem.WriteAllText _ ("C://testfile.txt", currentField, True) Next Catch ex As Microsoft.VisualBasic.FileIO.MalformedLineException MsgBox("Line " & ex.Message & " is invalid. Skipping") End Try End While End Using
Windows 98, Windows Server 2000 SP4, Windows Millennium Edition, Windows Server 2003, Windows XP Media Center Edition, Windows XP Professional x64 Edition, Windows XP SP2, Windows XP Starter Edition
The Microsoft .NET Framework 3.0 is supported on Windows Vista, Microsoft Windows XP SP2, and Windows Server 2003 SP1.Reference
TextFieldParser ClassTextFieldParser Members
Microsoft.VisualBasic.FileIO Namespace
TextFieldParser.ReadFields
Other Resources
TextFieldParser.ReadFields MethodTextFieldParser Object
TextFieldParser.TextFieldType Property
TextFieldParser.FieldWidths Property
TextFieldParser.Delimiters Property
How to: Read From a Comma-Delimited Text File in Visual Basic
How to: Read From a Fixed-width Text File in Visual Basic
How to: Read From a Text File with Multiple Formats in Visual Basic
Parsing Text Files with the TextFieldParser Object
TextFieldParser.ReadLine Method