String manipulation

[Jimmy_B]

Hey guys/girls,

I am still working on my practice exam for tomorrow and have another question.

If I have a text file that I am reading with streamreader and it contains various entries, some are names and some are grades. The names are in the text file in the following format: Alice MacLeod

What I want to know is how I could read that line and output it to a listbox in the following format: MacLeod, A

Any help would be appreciated.

This is what I have, but I can't seem to figure out how to get the last name. I have declared some variables that are not used yet, just ignore them.

Sub GetInfo()
Dim sr As IO.StreamReader
Dim name, fName, lName As String
Dim x, y, nameLength, space As Double
Dim numOfGrades As Double
sr = IO.File.OpenText("Lab5studentgrades.txt")
Do While sr.Peek <> -1
name = sr.ReadLine
nameLength = CDbl(name.Length)
lName = name.Substring(name.IndexOf(" "), nameLength - 1)
fName = name.Substring(0, 1)
lstOutput1.Items.Add("Name: " & lName & ", " & fName)
Loop
End Sub

[Kimmy4]

You can use the split function. Just say
Dim array as string()
array = name.split(" ")
and then firstname = array(0) and lastname = array(1)

Hope this helps

[stimbo]

As Kimmy said,

or to keep with your original method, although I changed the Streamreader and name length should be an Integer I think:

        Dim name, fName, lName As String
        Dim x, y, space As Double
        Dim numOfGrades As Double = 0
        Dim nameLength As Integer
        Dim break As Integer = 0


        Dim sr As New IO.StreamReader("names.txt")
        Do While sr.Peek <> -1
            name = sr.ReadLine
            nameLength = name.Length
            fName = name.Substring(0, 1)
            break = CInt(name.IndexOf(" ") + 1)
            lName = name.Substring(break, nameLength - break)
            Me.ListBox1.Items.Add("Name: " & lName & ", " & fName)
        Loop

        sr.Close()
        sr.Dispose()

[benmartin101]

try:

Dim sr As New System.IO.StreamReader("filename")
Dim str As String = sr.ReadLine()
Dim strAry() As String = str.Split(" ")
Dim dataYouWant As String = strAry(1) & ", " & strAry(0).SubString(0,1) 'this should output "MacLeod, A"

You'll have to figure out the loops to go thru the whole file

[Jimmy_B]

I got it working, thanks for the help!

[Jimmy_B]

Is it possible to make a loop stop when sr.peek reads a line containing "-1" ?

[stimbo]

Like this:

'Code
name = sr.ReadLine
If name = "-1" Then Exit Do
'Code

[Jimmy_B]

Like this:

'Code
name = sr.ReadLine
If name = "-1" Then Exit Do
'Code

hmm..that is what I thought, but for some reason I can't get it to work.

[Atheist]

Whats your code?

[calvin-c]

1) try it without the quotes. You might be running into a conversion issue. (you can also try explicit conversion)
2) I have better luck with checking for < 0 than = -1. (although it should work the same in this case)

[stimbo]

He's not referring to the end of stream (at least I don't think so...)

sr.peek reads a line containing "-1"

I take it he means the value of a string being "-1", hence the use of quotes.

I could be wrong though but his response seemed to indicate the answer was fine, it just wont work. It does for me though.

[Jimmy_B]

He's not referring to the end of stream (at least I don't think so...)

sr.peek reads a line containing "-1"

I take it he means the value of a string being "-1", hence the use of quotes.

I could be wrong though but his response seemed to indicate the answer was fine, it just wont work. It does for me though.

Yeah it is a string of "-1" that I am trying to read. I am going to work on it a bit more and see what I can do.