hi, i have a problem of Index was outside the bounds of the array. i don't understand how to amend the existing solution in my case. anyone could help me? the message error is System.IndexOutOfRangeException {"Index was outside the bounds of the array. below is the code & the error at line 109 (strTextOut = arrMicrosensor(intNum).strCode)

 Public Function sensorWithinRange() As MicrosensorStruct()

            Dim arrMicrosensor() As MicrosensorStruct                               '
            Dim dblNearestStation As MicrosensorStruct                              '
            Dim intStationCounter As Integer                                        'Counter for stations
            Dim dblStationE As Double                                               'Easting coords of one station
            Dim dblStationN As Double                                               'Northing coords of one station
            Dim intNearestSensor As Integer                                         '
            Dim strNearestSensor() As String                                        '
            Dim intA, intB, IntMaxIndex As Integer                                  '
            Dim dblMaxValue As Double                                               '
            Dim sMax, sTemp As MicrosensorStruct                                    '
            Dim strTextOut As String                                                '

            Dim strArrColumns() As String                                           'Columns within 1 station record
            Dim chrArrDelim() As Char = " ,".ToCharArray()                          'File delimiter

            Dim sReader As IO.StreamReader
            Dim strRecord As String

            intStationCounter = -1
            intNearestSensor = 0
            dblStationE = CDbl(txtEasting.Text)
            dblStationN = CDbl(txtNorthing.Text)

            sReader = IO.File.OpenText(txtFilename.Text)
            strRecord = sReader.ReadLine()

            strRecord = sReader.ReadLine()

            Do While (Not sReader.EndOfStream)

                strRecord = sReader.ReadLine()
                intStationCounter = (intStationCounter + 1)

            Loop

            sReader.Close()

            Dim intNrStations As Integer                                            'Total number of station
            ReDim arrMicrosensor(intNrStations)

            sReader = IO.File.OpenText(txtFilename.Text)
            strRecord = sReader.ReadLine()
            dblNearestStation.dblRngeDist = Double.PositiveInfinity

            For intStationCounter = 0 To intNrStations - 1
                strRecord = sReader.ReadLine()
                strArrColumns = strRecord.Split(chrArrDelim)

                arrMicrosensor(intStationCounter).lngID = CLng(strArrColumns(0))
                arrMicrosensor(intStationCounter).strOUTCORP = strArrColumns(1)
                arrMicrosensor(intStationCounter).strCode = strArrColumns(2)
                arrMicrosensor(intStationCounter).dblNorthing = CDbl(strArrColumns(3))
                arrMicrosensor(intStationCounter).dblEasting = CDbl(strArrColumns(4))
                arrMicrosensor(intStationCounter).dblRngeDist = CalculateDistance(dblStationN, dblStationE, arrMicrosensor(intStationCounter).dblNorthing, arrMicrosensor(intStationCounter).dblEasting)

                If arrMicrosensor(intStationCounter).dblRngeDist < CDbl(txtRangeDist.Text) Then
                    intNearestSensor = intNearestSensor + 1

                    'string for text in listbox
                    lboNearestStation.Items.Add("STATION ID:" &amp;amp; arrMicrosensor(intStationCounter).lngID.ToString &amp;amp; " , " _
                                        &amp;amp; "REFERENCE CODE:" &amp;amp; arrMicrosensor(intStationCounter).strCode &amp;amp; " , NORTHING:" _
                                        &amp;amp; arrMicrosensor(intStationCounter).dblNorthing.ToString("F") &amp;amp; ", EASTING:" _
                                        &amp;amp; arrMicrosensor(intStationCounter).dblEasting.ToString("F") &amp;amp; ", at:" _
                                        &amp;amp; arrMicrosensor(intStationCounter).dblRngeDist.ToString("F") &amp;amp; "m")

                End If

            Next intStationCounter
            sReader.Close()

            ReDim strNearestSensor(intNearestSensor - 1)

            For intStationCounter = 0 To intNrStations - 1
                If arrMicrosensor(intStationCounter).dblRngeDist < CDbl(txtRangeDist.Text) Then
                    intNearestSensor = 0
                    strNearestSensor(intNearestSensor) = arrMicrosensor(intStationCounter).strCode
                End If

            Next

            Dim intNum As Integer

            intNum = CInt(txtNrSensor.Text)

            'For intNum = 0 To intNum - 1
            For intNum = 0 To intNum - 1
                For intA = arrMicrosensor.GetUpperBound(0) To 1 Step -1

                    sMax = arrMicrosensor(0)
                    dblMaxValue = sMax.dblRngeDist
                    IntMaxIndex = 0

                    For intB = 0 To intA
                        If arrMicrosensor(intB).dblRngeDist &amp;gt; dblMaxValue Then
                            dblMaxValue = arrMicrosensor(intB).dblRngeDist
                            IntMaxIndex = intB

                        End If
                    Next intB

                    sTemp = arrMicrosensor(intA)
                    arrMicrosensor(intA) = arrMicrosensor(IntMaxIndex)
                    arrMicrosensor(IntMaxIndex) = sTemp

                Next intA

                strTextOut = arrMicrosensor(intNum).strCode

            Next intNum

            Return arrMicrosensor
        End Function

Recommended Answers

All 7 Replies

This is a vb.net question. I have asked the mods to move it there...

Your error occurs because you are looping through "intNum" but the last loop can not find the number. Remove the -1 at the start of your loop, should be fine then.

For intNum = 0 To intNum

This also seems like a problem because you are setting a value to intNum whilst looping intNum. Makes no sense to me. You should have something like...

intNum2 = 10

For intNum = 1 To intNum2 

ok, tq but I still stuck
here is the whole code of the program. hope you're willing to check it.

0

'--frmNearestMicLocation-----------------------------------------------------------------------------------
'   Calculate the nearest distance for
'   microsensor locations
'
'Form variables declared
'
'Command Buttons
'   cmdBrowseFolder         Browse to select the working directory
'   cmdStart                Test code with default base or start processing multiple points
'   cmdExit                 End program
'   cmdStats                Display the form of frmDisplaySensorHisto
'Textboxes
'   txtEasting              Eastings of point
'   txtNorthing             Northings of point
'   txtFilename             Shows directory selected with default input filename
'   txtRangeDist            Range distance
'Listboxes
'   lboNearestStation       Show the list of nearest station
'Dialogs
'   dlgOpenFile             Dialog to browse for the microsensors information file
'Dates
'   txtStartingDate         Allows users to choose the starting date    
'   txtEndingDate           Allows users to choose the ending date 

Option Explicit On
Option Strict On

Public Class frmNearestMicLocation

    '====CONSTANTS=======================

    Const dtmEARLYDATE As DateTime = #1/1/1970#
    Const strDEFAULTFILE As String = "\ibuttons_locations.csv"
    Const strENDFILE As String = ".csv"
    Const dblTEST_E As Double = 312773
    Const dblTEST_N As Double = 8027373

    'Temperature/Humidity Structure
    Public Structure MicrosensorStatsStruct
        Dim dblTemp As Double                             'Temperature of the data
        Dim dblHumi As Double                             'Humidity of the data
        Dim dblMaxTemp, dblMinTemp As Double              'Max and min temperature set by users
        Dim dblMaxHumi, dblMinHumi As Double              'Max and min humidity set by users 
        Dim dblMean As Double                             'Mean of the value set by users
        Dim dteDate As Date                               'The date updates
        Dim dteStartingDate As Date                       'The starting data update
        Dim dteEndingDate As Date                         'The ending data update
    End Structure

    'Microsensors Structure
    Public Structure MicrosensorStruct
        Dim lngID As Long                                 'The ID's number of the station
        Dim strOUTCORP As String                          'The OUTCORP for each station
        Dim strCode As String                             'The code of the ID
        Dim dblNorthing As Double                         'Northing coordinate of the data
        Dim dblEasting As Double                          'Esting coordinate of the data
        Dim dblRngeDist As Double                         'Range of distance
        Dim dteStart As Date                              'Starting date 
        Dim dteEnd As Date                                'Ending date
    End Structure

    '------------------------------------
    ' Select file with coordinates of microsensor locations
    '
    ' INPUTS: VB defaults
    ' OUTPUT: none

    Private Sub cmdBrowseFolder_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles cmdBrowseFolder.Click
        If dlgFolderBrowser.ShowDialog() = DialogResult.OK Then
            txtFilename.Text = dlgFolderBrowser.SelectedPath & strDEFAULTFILE
        End If

    End Sub

    '------------------------------------
    ' Set up form with initial values
    '
    ' INPUTS: VB defaults
    ' OUTPUT: none

    Private Sub frmNearestMicStation_Load(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles MyBase.Load
        Dim dblTEST_E As Double               '  
        Dim dblTEST_N As Double               '

        'set up form
        txtEasting.Text = CStr(dblTEST_E)
        txtNorthing.Text = CStr(dblTEST_N)

        txtEasting.Text = "312773"
        txtNorthing.Text = "8027373"
        dlgOpenFile.FileName = ""

    End Sub

    '------------------------------------
    'Start processing when cmdStart button is clicked
    '
    ' INPUTS: VB defaults
    ' OUTPUT: none

    Private Sub cmdStart_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles cmdStart.Click

        Dim arrMicrosensor() As MicrosensorStruct
        Dim arrMicrosensorData() As MicrosensorStatsStruct
        Dim intNum As Integer
        Dim strNearestSensor As String
        Dim strENDFILE As String
        Dim strFileName As String
        Dim arrTempHumi(,) As Double
        Dim intIndex As Integer
        Dim strSeriesName As String = CStr(1)

        If txtNrSensor.Text = "" Then
            MessageBox.Show("Fill in the number of sensors!")

        ElseIf txtNorthing.Text = "" Then
            MessageBox.Show("You haven't filled the Northing coordinate!")

        ElseIf txtEasting.Text = "" Then
            MessageBox.Show("You haven't filled the Easting coordinate!")

        ElseIf txtRangeDist.Text = "" Then
            MessageBox.Show("You haven't filled the range of distance!")

        Else
            arrMicrosensor = sensorWithinRange()

        intNum = CInt(txtNrSensor.Text)
        For intNum = 0 To intNum - 1

                strNearestSensor = dlgFolderBrowser.SelectedPath & "\" & arrMicrosensor(intNum).strCode &
                    strENDFILE
            strFileName = strNearestSensor & strENDFILE

                arrMicrosensorData = getSensorRecords(strNearestSensor)

                intIndex = frmDisplaySensorHisto.chrtMicroData.Series.IndexOf(strSeriesName)

            'Add missing series, if it is missing
            If intIndex < 0 Then
                frmDisplaySensorHisto.chrtMicroData.Series.Add(strSeriesName)
                intIndex = frmDisplaySensorHisto.chrtMicroData.Series.IndexOf(strSeriesName)

                'Add data
                For intI = 0 To arrMicrosensorData.GetUpperBound(0)
                        frmDisplaySensorHisto.chrtMicroData.Series.Item(intIndex).Points.AddXY(arrMicrosensorData(intI).dteDate, arrMicrosensorData(intI).dblTemp)

                Next intI

            End If

            'Call the calculate statistics
            CalculateStatistics(strFileName, arrTempHumi, arrMicrosensorData)

            'Display result in combo box
            frmDisplaySensorHisto.cboSelectSensor.Items.Add(arrMicrosensor(intNum).strCode)

            'List box text
            frmDisplaySensorHisto.lboSensorID.Items.Add("STATION ID: " & arrMicrosensor(intNum).lngID.ToString & " , " & "REFERENCE CODE: " & arrMicrosensor(intNum).strCode & " , NORTHING: " & arrMicrosensor(intNum).dblNorthing.ToString("F") & " , EASTING: " & arrMicrosensor(intNum).dblEasting.ToString("F") & " , at: " & arrMicrosensor(intNum).dblRngeDist.ToString("F") & "m")
            frmDisplaySensorHisto.Show()

        Next intNum
        End If

    End Sub

    '---CalculateDistance---------------------
    'Calculates the distance between a base and a point with projected coordinates
    'INPUTS: 
    '   dblBaseN, dblBaseE (double)         Base coordinates
    '   dblLocationN, dblLocationE (double) Point coordinates
    'OUTPUT: (double), distance between the two points, -9999.9999 is the default   
    Public Function CalculateDistance(ByVal dblBaseN As Double, ByVal dblBaseE As Double, _
                                          ByVal dblLocationN As Double, ByVal dblLocationE As Double) As Double
        Dim dblDist As Double               'straight-line distance between points
        Dim dblDeltaE, dblDeltaN As Double  'differences in easting and northing

        dblDeltaE = dblBaseE - dblLocationE
        dblDeltaN = dblBaseN - dblLocationN

        dblDist = Math.Sqrt(dblDeltaE ^ 2 + Math.Pow(dblDeltaN, 2))

        Return (dblDist)
    End Function

    '---CalculateBearing----------------------
    'Calculates the bearing between a base and a point with projected coordinates
    'INPUTS: 
    '   dblBaseN, dblBaseE (double)         Base coordinates
    '   dblLocationN, dblLocationE (double) Point coordinates
    'OUTPUT: (double), bearing of the line connecting the base with the point, -9999.9999 is the default   
    Public Function CalculateBearing(ByVal dblBaseN As Double, ByVal dblBaseE As Double, _
                                          ByVal dblLocationN As Double, ByVal dblLocationE As Double) As Double

        Dim dblDeltaE, dblDeltaN As Double  'differences in easting and northing
        Dim dblAngle As Double              'bearing uncorrected for quadrant
        Dim dblBearing As Double            'bearing from base to station

        'differences between base & station
        dblAngle = 0.0
        dblDeltaE = dblBaseE - dblLocationE
        dblDeltaN = dblBaseN - dblLocationN

        'avoid division by zero
        If dblDeltaN = 0 Then
            If (dblDeltaE < 0) Then
                dblBearing = 90 'directly east
            Else
                dblBearing = 270 'directly west
            End If

        Else
            dblAngle = Math.Atan(Math.Abs(dblDeltaE) / Math.Abs(dblDeltaN))
            dblAngle = dblAngle * 180.0 / Math.PI   'convert to degrees

            'adjust for quadrant
            If (dblDeltaE <= 0 And dblDeltaN < 0) Then 'Quadrant I
                dblBearing = dblAngle
            ElseIf (dblDeltaE <= 0 And dblDeltaN > 0) Then 'Quadrant II
                dblBearing = 180 - dblAngle
            ElseIf (dblDeltaE > 0 And dblDeltaN > 0) Then  'Quadrant III
                dblBearing = 180 + dblAngle
            Else 'Quadrant IV
                dblBearing = 360 - dblAngle
            End If
        End If

        Return (dblBearing)
    End Function

    '--- SensorWithinRange --------------------------------
    'Get the record from files and display it on the listbox
    'INPUTS:
    '       VB Defaults     
    'OUTPUT:
    '       2-D Arrays

    Public Function sensorWithinRange() As MicrosensorStruct()

        Dim arrMicrosensor() As MicrosensorStruct                               '
        Dim dblNearestStation As MicrosensorStruct                              '
        Dim intStationCounter As Integer                                        'Counter for stations
        Dim dblStationE As Double                                               'Easting coords of one station
        Dim dblStationN As Double                                               'Northing coords of one station
        Dim intNearestSensor As Integer                                         '
        Dim strNearestSensor() As String                                        '
        Dim intA, intB, IntMaxIndex As Integer                                  '
        Dim dblMaxValue As Double                                               '
        Dim sMax, sTemp As MicrosensorStruct                                    '
        Dim strTextOut As String                                                '

        Dim strArrColumns() As String                                           'Columns within 1 station record
        Dim chrArrDelim() As Char = " ,".ToCharArray()                          'File delimiter

        Dim sReader As IO.StreamReader
        Dim strRecord As String

        intStationCounter = -1
        intNearestSensor = 0
        dblStationE = CDbl(txtEasting.Text)
        dblStationN = CDbl(txtNorthing.Text)

        sReader = IO.File.OpenText(txtFilename.Text)
        strRecord = sReader.ReadLine()

        strRecord = sReader.ReadLine()

        Do While (Not sReader.EndOfStream)

            strRecord = sReader.ReadLine()
            intStationCounter = (intStationCounter + 1)

        Loop

        sReader.Close()

        Dim intNrStations As Integer                                            'Total number of station
        ReDim arrMicrosensor(intNrStations)

        sReader = IO.File.OpenText(txtFilename.Text)
        strRecord = sReader.ReadLine()
        dblNearestStation.dblRngeDist = Double.PositiveInfinity

        For intStationCounter = 0 To intNrStations - 1
            strRecord = sReader.ReadLine()
            strArrColumns = strRecord.Split(chrArrDelim)

            arrMicrosensor(intStationCounter).lngID = CLng(strArrColumns(0))
            arrMicrosensor(intStationCounter).strOUTCORP = strArrColumns(1)
            arrMicrosensor(intStationCounter).strCode = strArrColumns(2)
            arrMicrosensor(intStationCounter).dblNorthing = CDbl(strArrColumns(3))
            arrMicrosensor(intStationCounter).dblEasting = CDbl(strArrColumns(4))
            arrMicrosensor(intStationCounter).dblRngeDist = CalculateDistance(dblStationN, dblStationE, arrMicrosensor(intStationCounter).dblNorthing, arrMicrosensor(intStationCounter).dblEasting)

            If arrMicrosensor(intStationCounter).dblRngeDist < CDbl(txtRangeDist.Text) Then
                intNearestSensor = intNearestSensor + 1

                'string for text in listbox
                lboNearestStation.Items.Add("STATION ID:" & arrMicrosensor(intStationCounter).lngID.ToString & " , " _
                                    & "REFERENCE CODE:" & arrMicrosensor(intStationCounter).strCode & " , NORTHING:" _
                                    & arrMicrosensor(intStationCounter).dblNorthing.ToString("F") & ", EASTING:" _
                                    & arrMicrosensor(intStationCounter).dblEasting.ToString("F") & ", at:" _
                                    & arrMicrosensor(intStationCounter).dblRngeDist.ToString("F") & "m")

            End If

        Next intStationCounter
        sReader.Close()

        ReDim strNearestSensor(intNearestSensor - 1)

        For intStationCounter = 0 To intNrStations - 1
            If arrMicrosensor(intStationCounter).dblRngeDist < CDbl(txtRangeDist.Text) Then
                intNearestSensor = 0
                strNearestSensor(intNearestSensor) = arrMicrosensor(intStationCounter).strCode
            End If

        Next

        Dim intNum As Integer

        intNum = CInt(txtNrSensor.Text)

        For intNum = 0 To intNum - 1
            For intA = arrMicrosensor.GetUpperBound(0) To 1 Step -1

                sMax = arrMicrosensor(0)
                dblMaxValue = sMax.dblRngeDist
                IntMaxIndex = 0

                For intB = 0 To intA
                    If arrMicrosensor(intB).dblRngeDist > dblMaxValue Then
                        dblMaxValue = arrMicrosensor(intB).dblRngeDist
                        IntMaxIndex = intB

                    End If
                Next intB

                sTemp = arrMicrosensor(intA)
                arrMicrosensor(intA) = arrMicrosensor(IntMaxIndex)
                arrMicrosensor(IntMaxIndex) = sTemp

            Next intA

            strTextOut = arrMicrosensor(intNum).strCode

        Next intNum

        Return arrMicrosensor
    End Function

    '---GetSensorRecords-----------------------------------------
    ' will show us the nearby station of selected point
    'INPUTS: 
    '       VB defaults
    'OUTPUT: 
    '       The list of nearby station

    Public Function getSensorRecords(ByVal strFileName As String) As MicrosensorStatsStruct()

        Dim arrMicrosensorData() As MicrosensorStatsStruct      '
        Dim intNrStations As Integer                            '
        Dim intCounter As Integer                               '
        Dim strTextOut As String                                '
        Dim strRecords As String                                '
        Dim dblSensorTemp As Double                             '
        Dim dblSensorHumi As Double                             '
        Dim sReader As IO.StreamReader                          '
        Dim dtmDte As Date                                      '

        Dim strArrColumns() As String                           '
        Dim chrArrDelim() As Char = ", ".ToCharArray()          '

        'Get the array size
        ReDim arrMicrosensorData(intNrStations - 1)

        Try
            'Open stream
            sReader = IO.File.OpenText(strFileName)

            'Find the total lines number in the file
            intNrStations = 0

            Do Until sReader.EndOfStream
                strRecords = sReader.ReadLine()

                If strRecords <> "" Then
                    intNrStations = intNrStations + 1
                End If

            Loop

            intNrStations = intNrStations - 1
            sReader.Close()

            ReDim arrMicrosensorData(intNrStations - 1)

            'Save the values into the array
            sReader = IO.File.OpenText(strFileName)
            strRecords = sReader.ReadLine()

            For intNrStations = 0 To intNrStations - 1

                strRecords = sReader.ReadLine()
                'arrMicrosensorData = GetValuesFromString(strRecords)

                strArrColumns = strRecords.Split(chrArrDelim)

                dtmDte = CDate(strArrColumns(0))
                arrMicrosensorData(intCounter).dteDate = dtmDte

                dblSensorTemp = CDbl(strArrColumns(1))
                arrMicrosensorData(intCounter).dblTemp = dblSensorTemp

                dblSensorHumi = CDbl(strArrColumns(2))
                arrMicrosensorData(intCounter).dblHumi = dblSensorHumi

                strTextOut = "Date Time: " & arrMicrosensorData(intCounter).dteDate.ToString & " Temperature: " & CStr(arrMicrosensorData(intCounter).dblTemp).ToString & ("°C") & " , Humidity: " & ("%")
                lboMicrosensorData.Items.Add(strTextOut)

            Next intNrStations

            sReader.Close()

        Catch noFileErr As IO.FileNotFoundException
            MessageBox.Show("Check your file!")

        Catch ioErr As IO.IOException
            MessageBox.Show("File not found!")

        Catch exNull As ArgumentException
            MessageBox.Show("Invalid argument!")
            arrMicrosensorData = Nothing

        End Try

        Return arrMicrosensorData

    End Function

    'Converts a comma-delimited String of Sensor data
    'into MeteodataStruct type
    'INPUT: strRecord (String(,)) - Sensor records
    'OUTPUT: (MeteodataStruct()) - Sensor records
    '=====================================================================================

    Public Function GetValuesFromString(ByVal strRecord As String, ByRef Microsensordata As MicrosensorStatsStruct) As MicrosensorStatsStruct
        Dim chrArrDelim() As Char = ",".ToCharArray()   'delimiter
        Dim strArrColumns() As String                   'columns within record

        'add error traps
        Microsensordata.dteDate = Nothing
        Microsensordata.dblTemp = -9999999
        Microsensordata.dblHumi = -9999999

        Try
            'split record
            strArrColumns = strRecord.Split(chrArrDelim)

            'convert types and save
            Microsensordata.dteDate = GetDateFromString(strArrColumns(0))
            Microsensordata.dblTemp = CDbl(strArrColumns(1))
            Microsensordata.dblHumi = CDbl(strArrColumns(2))

        Catch errInput As InvalidCastException
            MessageBox.Show("Check the input!")
        End Try

        Return Microsensordata

    End Function

    'Converts a string (in format dd/mm/yyyy)
    'into a date object. 
    'If format is invalid, returns Nothing
    'REF: E-K Gulland 1 May 2012
    'INPUT: strDate (String) - date as text dd/mm/yyyy
    'OUTPUT: (DateTime) - date object
    '===========================================================================

    Private Function GetDateFromString(ByVal strDate As String) As DateTime
        Dim dteDate As DateTime = Nothing                 '
        Dim chrArrDelim() As Char = "/".ToCharArray()     'delimiter
        Dim strArrColumns() As String                     'columns within record
        Dim intDay, intMonth, intYear As Integer          'components of date

        Try
            strArrColumns = strDate.Split(chrArrDelim)

            intDay = CInt(strArrColumns(0))
            intMonth = CInt(strArrColumns(1))
            intYear = CInt(strArrColumns(2))

            dteDate = New DateTime(intYear, intMonth, intDay)

        Catch castErr As InvalidCastException
            dteDate = Nothing 'invalid date format

        Catch indexErr As IndexOutOfRangeException
            dteDate = Nothing 'missing component or didn't use "/"

        Catch dateErr As ArgumentOutOfRangeException
            dteDate = Nothing 'day, month or year invalid

        End Try

        Return dteDate

    End Function

    'Title:  Subroutine CalculateStatistics
    'Calculates the Min and Max values for a selected statistics for a selected sensor
    'INPUTS 
    '   lngSensorID     ID of the selected sensor
    '   Statistics      The desired statistics
    'OUTPUT 
    '   Min and Max values
    '====================================================================================

    Public Function CalculateStatistics(ByVal strFileName As String, ByRef arrTempHumi(,) As Double, ByRef arrMicrosensorData() As MicrosensorStatsStruct) As Double(,)
        Dim dblMinTemp As Double                      '
        Dim dblMaxTemp As Double                      '   
        Dim dblMinHumi As Double                      '
        Dim dblMaxHumi As Double                      '
        Dim dteStartingDate As Date                   '
        Dim dteEndingDate As Date                     '
        Dim strTextOut As String                      '

        ReDim arrTempHumi(0, 3)

        'initialize
        dblMaxTemp = Double.NegativeInfinity
        dblMinTemp = Double.PositiveInfinity
        dblMaxHumi = Double.NegativeInfinity
        dblMinHumi = Double.PositiveInfinity
        dteStartingDate = dtpStartingDate.Value
        dteEndingDate = dtpEndingDate.Value

        Try
            If arrMicrosensorData IsNot Nothing Then

                For intI = 0 To arrMicrosensorData.GetUpperBound(0)
                    If ((arrMicrosensorData(intI).dteDate >= dteStartingDate) And (arrMicrosensorData(intI).dteDate <= dteEndingDate)) Then

                        If arrMicrosensorData(intI).dblTemp > dblMaxTemp Then
                            dblMaxTemp = arrMicrosensorData(intI).dblTemp
                        End If

                        If arrMicrosensorData(intI).dblTemp < dblMinTemp Then
                            dblMinTemp = arrMicrosensorData(intI).dblTemp
                        End If
                        If arrMicrosensorData(intI).dblHumi > dblMaxHumi Then
                            dblMaxHumi = arrMicrosensorData(intI).dblHumi
                        End If
                        If arrMicrosensorData(intI).dblHumi > dblMinHumi Then
                            dblMinHumi = arrMicrosensorData(intI).dblHumi
                        End If
                    End If

                Next intI
            End If

        Catch exNull As NullReferenceException
            MessageBox.Show("Bad file Format")
        End Try

        arrTempHumi(0, 0) = dblMaxTemp
        arrTempHumi(0, 1) = dblMinTemp
        arrTempHumi(0, 2) = dblMaxHumi
        arrTempHumi(0, 3) = dblMinHumi

        strTextOut = "MaxTemp: " & arrTempHumi(0, 0).ToString & "(°C)" & "," & "MinTemp: " & arrTempHumi(0, 1).ToString & "(°C)" & "," & "MaxHumi: " & arrTempHumi(0, 2).ToString & "," & "MinHumi" & arrTempHumi(0, 3).ToString

        frmDisplaySensorHisto.lboStats.Items.Add(strTextOut)

        Return arrTempHumi

    End Function

    Private Sub cmdExit_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles cmdExit.Click
        Me.Close()
    End Sub
End Class

As I suspected, you gave a value to intNum and then tried to loop through the value wich is constant/static...

Try thye following...

intNum = CInt(txtNrSensor.Text) ''Lets say 17 is returned...

Dim intLoop As Integer ''We'll be using THIS to loop through all sensors...
    For intLoop = 1 To intNum ''Loop from 1, 0 will be a non-existing sensor. Remove -1, we want to loop through every sensor from 1 to last sensor, not second last...

    ''All your code and inner loops here as you have it...
Next intLoop ''Will loop 17 times, no error...

owh, ok i'll try again.
TQ so much

Lines 40 and 41 of your OP.

Dim intNrStations As Integer 'Total number of station
ReDim arrMicrosensor(intNrStations)

The array "arrMicrosensor" has a length of 1 after these statements execute as "intNrStations" will have an initial value of zero. "ReDim arrMicrosensor(intNrStations)" is equivalent to: ReDim arrMicrosensor(0 To 0); therefore, any array index reference greater than zero will cause an out of bounds error.

Also remember that in Vb.Net arrays use zero based indexing.

Thanx TinMn, did not even go further than original error on line 190.

yat, have a look at the above, might throw errors as well....

Be a part of the DaniWeb community

We're a friendly, industry-focused community of developers, IT pros, digital marketers, and technology enthusiasts meeting, networking, learning, and sharing knowledge.