TextFieldParser.PeekChars(Int32) Method

public:
 System::String ^ PeekChars(int numberOfChars);

public string? PeekChars(int numberOfChars);

public string PeekChars(int numberOfChars);

member this.PeekChars : int -> string

Public Function PeekChars (numberOfChars As Integer) As String

Parameters

Returns

A string that contains the specified number of characters read.

Exceptions

Examples

This example uses PeekChars to find the end of the data and stop parsing the file at that point.

Using MyReader As New Microsoft.VisualBasic.FileIO.TextFieldParser("C:\ParserText.txt")
 MyReader.TextFieldType = Microsoft.VisualBasic.FileIO.FieldType.Delimited
 MyReader.Delimiters = New String() {","}
 MyReader.CommentTokens = New String() {"'"}
 Dim currentRow As String()
 While (MyReader.PeekChars(1) IsNot "")
 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

Remarks

The numberOfChars value must be less than the total number of characters in the line. If it is not, the string returned by PeekChars will be truncated to the length of the line.

Blank lines are ignored.

End-of-line characters are not returned.

The PeekChars method performs no parsing; an end-of- line character within a delimited field is interpreted as the actual end of the line.

The following table lists examples of tasks involving the PeekChars method.

See also

• OpenTextFieldParser(String)
• Objects (Visual Basic)
• Parsing Text Files with the TextFieldParser Object
• Reading from Files in Visual Basic