Question

I have a .csv file which has data but not the column headers. I can able to create new .csv file with oldcsv file’s content. But I need to add column headers in first row and from second row the existing data should appear.

Here is the code I have written:

 Dim ioFile As New System.IO.StreamReader("C:\sample.csv")      
 Dim ioLine As String      Dim ioLines As String      
 ioLine = ioFile.ReadLine     
 ioLines = ioLine     
 While Not ioLine = ""         
    ioLine = ioFile.ReadLine         
    ioLines = ioLines & vbCrLf & ioLine      
 End While     
 Dim ioWriter As New System.IO.StreamWriter("C:\new.csv")     
 ioWriter.WriteLine(ioLines)     
 ioFile.Close()     
 ioWriter.Close() 

Now i need to add column headers in new.csv as “ID”,”Name”,”Number”,”Amount”

Answer 1

You can set up the Reader and Writer to read and write within the loop and avoid creating a oiLines construct.

Dim reader as New StreamReader(inputFileName)
Dim writer as New StreamWriter(outputFileName)
Dim line as String

'Do you have a definition of what has to be added here?
writer.WriteLine(headerLine)

While (Nothing <> (line = reader.ReadLine()))
  writer.WriteLine(line)
End While

reader.Dispose()
writer.Dispose()

Check the code, as I wrote it blind. I am more C#, but the idea is sound. You just need to supply the inputFileName, outputFileName and headerLine. This also allows putting this in a method, where it is reuseable. 🙂