[RESOLVED] Still stuck !

[Paul the Rookie]

Posted the other day.......
There is prbably a better way to read form a text file using stream reader and compare to the text in a text box.... this is what I have..... It produces an out of bounds error but I still cant see why !

Private Sub Button1_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button1.Click
intOccur = 0
Dim intSeekStart As Integer = 0
Dim intStrLen As Integer = TextBox1.Text.Length
If TextBox1.Text <> "" Then
If OpenFileDialog1.ShowDialog() = DialogResult.OK Then
Dim fsStream As New FileStream(OpenFileDialog1.FileName, FileMode.Open, FileAccess.Read)
Dim srReader As New StreamReader(fsStream)
Do
Dim chrCheckString(TextBox1.Text.Length - 1) As Char
srReader.Read(chrCheckString, intSeekStart, intStrLen)
Dim strCompare As New String(chrCheckString)
If strCompare.ToUpper = TextBox1.Text.ToUpper Then
intOccur += 1
Label1.Text = "Occurences = " & CStr(intOccur)
chrCheckString = Nothing
End If
intSeekStart += 1
Loop While (intSeekStart <= (srReader.BaseStream.Length - intSeekStart))
srReader.Close()
End If
End If
End Sub

[Atheist]

Where does the OutOfBounds exception occur?

[.paul.]

its something like:

Do while srReader.peek <> -1

[Paul the Rookie]

But I need to read x No. of characters into the array and compare them to a known string !

[.paul.]

if you want to post an example of the file you're parsing, i'll try it for you

[Atheist]

Shouldnt the loop condition be this?

Loop While (intSeekStart <= (srReader.BaseStream.Length - intStrLen))

[Paul the Rookie]

What i dont understand is that chrCheckstring contains the correct value and the indexes are all 4 which should be ok... but the loop throws the out of bounds exception after only one iteration ??

[Atheist]

What i dont understand is that chrCheckstring contains the correct value and the indexes are all 4 which should be ok... but the loop throws the out of bounds exception after only one iteration ??

What line?

[Paul the Rookie]

srReader.Read(chrCheckString, intSeekStart, intStrLen)
this line causes the error but the 2 values are both 4

[Atheist]

The second argument of the Read method specifies on what index in the char array that you will start writing too. You should keep it to 0 at all times.
On the second iteration, what it will try to do is to write X number of chars to an array that can hold X number of chars, but start writing at index 1. It will obviously go out of bounds.
For each call to the Read method, the StreamReader advances in the stream, so your intSeekStart variable really isnt needed.