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Returns the current line as a string and advances the cursor to the next line.
public:
System::String ^ ReadLine();
public string? ReadLine();
public string ReadLine();
member this.ReadLine : unit -> string
Public Function ReadLine () As String
The current line from the file or stream.
This example reads through the file ParserText.txt
and writes it 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.ReadLine()
My.Computer.FileSystem.WriteAllText(
"C://testfile.txt", currentRow, True)
Catch ex As Microsoft.VisualBasic.FileIO.MalformedLineException
MsgBox("Line " & ex.Message & " is invalid. Skipping")
End Try
End While
End Using
If Testfile.txt
does not exist, it is created by the WriteAllText
method.
This example writes the fields as a single string; to have each line display on its own line in the destination file, a VbCrLf
character should be appended at the end of each line.
The ReadLine
method performs no parsing; an end-of-line character within a delimited field is interpreted as the actual end of the line.
Nothing
is returned if the end of the file is reached.
Product | Versions |
---|---|
.NET | Core 3.0, Core 3.1, 5, 6, 7, 8, 9, 10 |
.NET Framework | 2.0, 3.0, 3.5, 4.0, 4.5, 4.5.1, 4.5.2, 4.6, 4.6.1, 4.6.2, 4.7, 4.7.1, 4.7.2, 4.8, 4.8.1 |
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