How to auto fill a textbox from a comobobox using a textfile - vb.net

Question

I 'm currently creating a form in VB that uses a text file to gather information for a combo box then automatic use the next word in the text file that's comma delimited to automatically populate a textbox.
But the current code I wrote show the list for the combo box but always auto fills the textbox with the second word on the second line and will not change the textbox after i select another option from the combo box can someone help?
Sorry if this isn't very clear.
My Text file is in this format:
Robert,5 BellView Road
Martin,6 BellView Road
Ect....
My code is as follows:
Dim LineString As String
Dim FieldString As String()
Try
Dim ContactInfoStreamReader As StreamReader = New StreamReader("C:\temp\test1.txt")
Do Until ContactInfoStreamReader.Peek = -1
LineString = ContactInfoStreamReader.ReadLine()
FieldString = LineString.Split(CChar(","))
LineString = FieldString(0)
ComboBox1.Items.Add(LineString)
Loop
RichTextBox2.Text = FieldString(1)
ContactInfoStreamReader.Close()
Catch ex As Exception
MsgBox("""Customers Name & Address.txt"" file was not found")
End Try

Answer 1

Ok, I know you have provided code, however this is how I would do it.
First of all we make a Person Class and create a Person List to store each Person
After that we read / load the text file into a string array and then we use Linq to split the text files line where the comma is and have it sort the name and address into two keys one being NAME and the other being ADDRESS. Once that is done we loop through each of the items and create a new Person with the values value.NAME and Value.Address for the persons name and address as well as add the person's name into a comboboxand finally we add a ComboBox Event that changes the Textbox's text to the selected ComboBox's Index that matches the List of People that was created to store each Person
Public Class Form1
Dim People As New List(Of Person)
Private Sub ComboBox1_SelectedValueChanged(sender As Object, e As EventArgs) Handles ComboBox1.SelectedValueChanged
Try
TextBox1.Text = People(ComboBox1.SelectedIndex).address
Catch
''this will prevent errors if there is a name with no address
TextBox1.Text = ""
End Try
End Sub
Private Sub Form1_Load(sender As Object, e As EventArgs) Handles MyBase.Load
''This is the location I used, feel free to change it here.
Dim location As String = Environment.GetFolderPath(Environment.SpecialFolder.Desktop)
Dim fileName As String = "test1.txt"
Dim path As String = System.IO.Path.Combine(location, fileName)
Dim query = From line In System.IO.File.ReadAllLines(path)
Let val = line.Split(",")
Select New With {Key .NAME = val(0), Key .ADDRESS = val(1)}
For Each value In query
Dim p = New Person(value.NAME, value.ADDRESS)
People.Add(p)
ComboBox1.Items.Add(value.NAME)
Next
''ADD OTHER COMBOBOX ITEMS HERE IF NEED BE, SO EVERYTHING IS IN ORDER
ComboBox1.Items.Add("ANDREW")
End Sub
End Class
Class Person
Public Property name() As String
Public Property address() As String
Public Sub New(name As String, address As String)
Me.name = name
Me.address = address
End Sub
End Class
EDIT:This is how I formatted the text file.Robert,5 BellView Road
Martin,6 BellView Road