IndexOutOfRangeException in pinging application

I am having an exception when running the function PingTest() in terms of the array I'm using. I'm not entirely sure how this is happening. Here is all the code.

Code:

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    Dim pingTo As String = "www.google.com"
    Dim amountOfTests As Integer = 10
    Dim testIterations(amountOfTests - 1) As Integer

    Public Function AverageOfTests() As Boolean
        Dim average As Double
        For count As Integer = 0 To amountOfTests
            average = average + testIterations(count)
            count += 1
        Next
        txtResults.Text += average

        Return True
    End Function

    Public Function PingTest() As Boolean
        For count As Integer = testIterations(count) To amountOfTests
            count += 1
            Dim ping As New System.Net.NetworkInformation.Ping
            Dim ms = ping.Send(pingTo).RoundtripTime()
            txtResults.Text += System.Environment.NewLine
            txtResults.Text += "pinged (" & pingTo & ") at " & ms & "."
            testIterations(count) = CInt(ms)

        Next
        AverageOfTests()
        Return True
    End Function

    Private Sub btnStart_Click(sender As Object, e As EventArgs) Handles btnStart.Click
        txtResults.Clear()
        PingTest()
    End Sub

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Try this:

Code:

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For count As Integer = 0 To amountOfTests - 1

---

Typically, you do not modify the indexing variable (count) within the For-Next block.
Remove

Code:

---

count += 1

---

from the For-Next blocks or change to one of the Do loop constructs.

Quote:

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Originally Posted by TnTinMN

Typically, you do not modify the indexing variable (count) within the For-Next block.
Remove

Code:

---

count += 1

---

from the For-Next blocks or change to one of the Do loop constructs.

---

Didn't spot that...

I get an error under the AverageOfTests() function

Error:
System.IndexOutOfRangeException

The error occurs on the line
average = average + testIterations(count)

New code:

Code:

---

    Dim pingTo As String = "www.google.com"
    Dim amountOfTests As Integer = 10
    Dim testIterations(amountOfTests - 1) As Integer

    Public Function AverageOfTests() As Boolean
        Dim average As Double
        For count As Integer = 0 To amountOfTests
            average = average + testIterations(count)
            count += 1
        Next
        txtResults.Text += average

        Return True
    End Function

    Public Function PingTest() As Boolean
        For count As Integer = 0 To amountOfTests - 1
            count += 1
            Dim ping As New System.Net.NetworkInformation.Ping
            Dim ms = ping.Send(pingTo).RoundtripTime()
            txtResults.Text += System.Environment.NewLine
            txtResults.Text += "pinged (" & pingTo & ") at " & ms & "."
            testIterations(count) = CInt(ms)

        Next
        AverageOfTests()
        Return True
    End Function

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Also for this, I need a value to increment to stop it at some point. What would be the correct way to do that?

Quote:

---

Originally Posted by TnTinMN

Typically, you do not modify the indexing variable (count) within the For-Next block.
Remove

Code:

---

count += 1

---

from the For-Next blocks or change to one of the Do loop constructs.

---

change:

Code:

---

For count As Integer = 0 To amountOfTests - 1
    average = average + testIterations(count)
Next

---

in your AverageOfTests function

and remove:

Code:

---

count += 1

---

from your PingTest code

I removed the count += 1. Why do I have to? Does it automagically increment by 1?

Quote:

---

Originally Posted by .paul.

change:

Code:

---

For count As Integer = 0 To amountOfTests - 1
    average = average + testIterations(count)
Next

---

in your AverageOfTests function

and remove:

Code:

---

count += 1

---

from your PingTest code

---

Also

Code:

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        Dim response As String = InputBox("Enter an IP address or website.")
        If Len(response) > 0 Then
            If response.Contains("http://") Then
                MsgBox("Please enter a valid website address.")
                pingTo = "www.google.com"
               
            Else
                response.Replace("http://", Nothing)
                response.Replace("https://", Nothing)
               
            End If
        Else
        End If

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Also, the contains ("https://") executes even though the string doesn't contain it.

EDIT I FIXED MY LOGICAL ERROR.

Code:

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for x as integer = 1 to 5
    msgbox(x.ToString)
next

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5 msgboxes will pop up one after another... 1,2,3,4,5
The for next block increments itself.

OH, thanks for explaining that bit.

Quote:

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Originally Posted by .paul.

Code:

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for x as integer = 1 to 5
    msgbox(x.ToString)
next

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5 msgboxes will pop up one after another... 1,2,3,4,5
The for next block increments itself.

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