How can calculate the number of columns in a textfile and show in a textbox, in vb.net?-CodePudding

I have a textfile (data.txt) with 3 columns, each column with one variable (x1, x2 and x3). I would like to calculate a number of columns and show in a specific textbox (like textbox1). For example. My data.txt:

x1 x2 x3
10 15 20
20 10 10

TextBox1 needs to show: 3

CodePudding user response：

You use delimiter like present in the file. I use Space here

Sub test1()
    
    Dim FileNum As Integer
    Dim DataLine As String
    
    FileNum = FreeFile()
    
    Filename = "C:\test.txt"
    Open Filename For Input As #FileNum
    
    Lines = Split(Input$(LOF(FileNum), #FileNum), vbNewLine)
    
    colnum = Split(Lines(1), " ")
    
    MsgBox "No of Columns in the file is " & UBound(colnum)   1
    
    End Sub

CodePudding user response：

Text files don't have columns. What you have is a file where each line separates elements by a space and each row is separated by a CR/LF (carraige return/line feed) To work with the text file put

Imports System.IO

at the top of the code file.

I am guessing that you will want to do more with the file than just determin the number of "columns" so, we will read the entire file. File.ReadAllLines() returns an array of lines in the file.

We take the first line in the file (index 0) and split it by a space. The lowere case c followint " " tells the compiler that you mean a Char not a String. Then we take the Length of the resulting array to find the number of columns.

Private Sub Button1_Click(sender As Object, e As EventArgs) Handles Button1.Click
    Dim lines = File.ReadAllLines("C:\Users\******\Desktop\Code\OPdata.txt")
    Dim NoOfColumns = lines(0).Split(" "c).Length
    TextBox1.Text = NoOfColumns.ToString
    'Some other things you can do
    Dim dt As New DataTable
    Dim columns = lines(0).Split(" "c)
    dt.Columns.Add(columns(0), GetType(Integer))
    dt.Columns.Add(columns(1), GetType(Integer))
    dt.Columns.Add(columns(2), GetType(Integer))
    For index = 1 To lines.Length - 1
        Dim values = lines(index).Split(" "c)
        dt.Rows.Add({values(0), values(1), values(2)})
    Next
    DataGridView1.DataSource = dt
End Sub