I try to generate 10 random integers and store it in an array(9). Then I split the array into half by converting it into string. My code can compile but it sometimes work and most time cannot work. I don't know what is the problem....

Public Class Form1

    Private Sub Button1_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button1.Click

        Dim rand As New Random
        Dim array(9) As String
        Dim X As String
        Dim Y As String
        Dim i As Integer

        For i = 0 To 9
            array(i) = rand.Next
            i = i + 1

        Dim HiOrder As String = array(0).Substring(0, 5)
        Dim LoOrder As String = array(0).Substring(5, 5)

        X = 1.3 + (HiOrder * ((2.4 - 1.3) / ((10 ^ 5) - 1)))
        Y = 3.4 + (LoOrder * ((4.7 - 3.4) / ((10 ^ 5) - 1)))

        ListBox1.Items.Add("X = " & X)
        ListBox1.Items.Add("Y = " & Y)

    End Sub

    Private Sub Form1_Load(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles MyBase.Load
    End Sub

End Class

Can help me with this??? I can't seem to get it to run every time....

Edited 6 Years Ago by __avd: Added [code] tags. For easy readability, always wrap programming code within posts in [code] (code blocks)


will create a random number between 0 and Int32.MaxValue

so if the random number is smaller than 9999 then "array(0).Substring(0, 5)" will fail
to make sure it dont fail do


First time might be u r getting array(0) is 10 digits and when click again the button, arrya(0) holding 9 digits. So when your are trying to use substring(5,5), length is not correct thats what throwing the exception.

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