Reads a single line from an open sequential file and assigns it to a String variable.

Public Function LineInput(ByVal FileNumber As Integer) As String

Parameters

FileNumber

Required. Any valid file number.

Exceptions/Errors

Remarks

Data read with LineInput is usually written to a file with Print.

Security Note   When reading from files, do not make decisions about the contents of a file based on the file name extension. For example, a file named Form1.vb may not be a Visual Basic .NET source file.

The LineInput function reads from a file one character at a time until it encounters a carriage return (Chr(13)) or carriage return–linefeed (Chr(13) + Chr(10)) sequence. Carriage return–linefeed sequences are skipped rather than appended to the character string.

Security Note   Reading from a file with the LineInput function requires Read assess from the FileIOPermissionAccess enumeration. For more information, see FileIOPermissionAccess Enumeration.

Example

This example uses the LineInput function to read a line from a sequential file and assign it to a variable. This example assumes that TESTFILE is a text file with a few lines of sample data.

Dim TextLine As String
FileOpen(1, "TESTFILE", OpenMode.Input)   ' Open file.
While Not EOF(1)   ' Loop until end of file.
   TextLine = LineInput(1)   ' Read line into variable.
   Debug.WriteLine(TextLine)   ' Print to the console.
End While
FileClose(1)   ' Close file.

Requirements

Namespace: Microsoft.VisualBasic

Module: FileSystem

Assembly: Microsoft Visual Basic .NET Runtime (in Microsoft.VisualBasic.dll)

See Also

Chr, ChrW Functions | Input Function | EndOfStreamException Class | IOException Class