TextFieldParser Class
Provides methods and properties for parsing structured text files.
Assembly: Microsoft.VisualBasic (in Microsoft.VisualBasic.dll)
For more detailed information, see the Visual Basic topic TextFieldParser Object.
The TextFieldParser object provides methods and properties for parsing structured text files. Parsing a text file with the TextFieldParser is similar to iterating over a text file, while the ReadFields method to extract fields of text is similar to splitting the strings.
The TextFieldParser can parse two types of files: delimited or fixed-width. Some properties, such as Delimiters and HasFieldsEnclosedInQuotes are meaningful only when working with delimited files, while the FieldWidths property is meaningful only when working with fixed-width files.
The following table lists examples of tasks involving the Microsoft.VisualBasic.FileIO.TextFieldParser object.
To | See |
|---|---|
Read from a delimited text file | How to: Read From Comma-Delimited Text Files in Visual Basic |
Read from a fixed-width text file | |
Read from a text file with multiple formats | How to: Read From Text Files with Multiple Formats in Visual Basic |
This example parses through a tab-delimited text file, Bigfile.
Using MyReader As New Microsoft.VisualBasic.FileIO.TextFieldParser _ ("c:\logs\bigfile") MyReader.TextFieldType = Microsoft.VisualBasic.FileIO.FieldType.Delimited MyReader.Delimiters = New String() {vbTab} Dim currentRow As String() 'Loop through all of the fields in the file. 'If any lines are corrupt, report an error and continue parsing. While Not MyReader.EndOfData Try currentRow = MyReader.ReadFields() ' Include code here to handle the row. Catch ex As Microsoft.VisualBasic.FileIO.MalformedLineException MsgBox("Line " & ex.Message & _ " is invalid. Skipping") End Try End While End Using
This example depends on the existence of a function, processFields, which processes the fields as they are read.
Windows 7, Windows Vista, Windows XP SP2, Windows XP Media Center Edition, Windows XP Professional x64 Edition, Windows XP Starter Edition, Windows Server 2008 R2, Windows Server 2008, Windows Server 2003, Windows Server 2000 SP4, Windows Millennium Edition, Windows 98
The .NET Framework and .NET Compact Framework do not support all versions of every platform. For a list of the supported versions, see .NET Framework System Requirements.