Trade Reconciliation Macro - arrays

Question

I'm trying to write a macro that will reconcile two trade reports by putting a yellow fill on trades listed on Sheet1 that are missing from Sheet2 and vice versa. I am a beginner to VBA and have been learning as I go along. Basically the approach that I have taken has been to iterate through each row on Sheet1, creating an array for each of the main fields being compared (TradeDate, Ticker, and Quantity). These arrays contain the row numbers of every match with that field in Sheet1 that is found in Sheet2. Once the arrays are created, I would like to compare the arrays and check if the same row number is contained in each. If so, the program should move on to the next trade. If not, that row should be marked with a yellow fill on Sheet1. I keep getting run-time errors for type mismatch, any input as to why?
Sub Reconciliation()
Sheets("Sheet1").Select
Dim LastRow As Long
Dim LastRow2 As Long
Dim rowCounter As Long
Dim isZero As Long
LastRow = ActiveSheet.UsedRange.Rows.Count
With Sheets("Sheet2").Select
LastRow2 = ActiveSheet.UsedRange.Rows.Count
End With
isZero = 1
'Loops through every row on Sheet 1
For rowCounter = 2 To LastRow
Dim DateValue As String
DateValue = ActiveSheet.Cells(8, rowCounter)
'Search Sheet2 for TradeDate and add matched rows to DateArray
Dim DateArray() As Long
ReDim DateArray(0 To LastRow2)
Sheets("Sheet2").Select
If Application.WorksheetFunction.CountIf(Range("E2:E" & LastRow2), DateValue) > 0 Then
isZero = isZero * 0
Else
DateArray(0) = Application.Match(DateValue, Range("E2:E" & LastRow2), 0)
Dim i As Integer
Dim x As Integer
x = 1
For i = 1 To LastRow2
If Application.Match(DateValue, Range("E" & DateArray(x - 1) & ":E" & LastRow2), 0) = "IsError" Then
Exit For
Else
DateArray(x) = Application.Match(DateValue, Range("E" & DateArray(x - 1) & ":E" & LastRow2), 0)
x = x + 1
End If
Next i
End If
Dim tickerValue As String
tickerValue = ActiveSheet.Cells(4, rowCounter)
Dim TickerArray() As Long
ReDim TickerArray(0 To LastRow2)
Sheets("Sheet2").Select
If Application.Match(tickerValue, Range("D2:D" & LastRow2), 0) = "IsError" Then
isZero = isZero * 0
Else
TickerArray(0) = Application.Match(tickerValue, Range("D2:D" & LastRow2), 0)
Dim i1 As Integer
Dim x1 As Integer
x = 2
For i1 = 1 To LastRow2
If Application.Match(tickerValue, Range("D" & TickerArray(x1 - 1) & ":D" & LastRow2), 0) = "IsError" Then
Exit For
Else
ReDim Preserve TickerArray(0 To x1)
TickerArray(x1) = Application.Match(tickerValue, Range("D" & TickerArray(x1 - 1) & ":D" & LastRow2), 0)
x1 = x1 + 1
End If
Next i1
End If
Dim quantityValue As Long
quantityValue = ActiveSheet.Cells(3, rowCounter)
Dim QuantityArray() As Long
ReDim QuantityArray(0 To LastRow2)
Sheets("Sheet2").Select
If Application.Match(quantityValue, Range("E2:E" & LastRow2), 0) = "N/A" Then
isZero = isZero * 0
Else
QuantityArray(0) = Application.Match(quantityValue, Range("E2:E" & LastRow2), 0)
Dim i2 As Integer
Dim x2 As Integer
x2 = 2
For i2 = 1 To LastRow2
If Application.Match(quantityValue, Range("E" & QuantityArray(x2 - 1) & ":E" & LastRow2), 0) = "IsError" Then
Exit For
Else
ReDim Preserve QuantityArray(0 To x2)
QuantityArray(x2) = Application.Match(quantityValue, Range("E" & QuantityArray(x2 - 1) & ":E" & LastRow2), 0)
x2 = x2 + 1
End If
Next i2
End If
Next rowCounter
End Sub

Answer 1

So there's quite a few problems with your code. Some of it is style, some of it is syntax.
First every place that you have a:
Application.Match(...)
It needs to have WorksheetFunction in between Application and Match so it reads:
Application.WorksheetFunction.Match(...)
Second try to avoid dimensioning variables inside your loops. There's no need for it, and if you want to reset your variables after each loop then add something like a var = 0 at the end.
Move DateValue and DateArray out of the For Loop. Dim DateArray once after LastRow(2) since that's the only time you do and LastRow(2) never changes.
The same goes for TickerArray, tickerValue, QuantityArray, and quantityValue.
Third avoid variables with numbers in them, i.e. LastRow2. This is when you need to use either a more descriptive variable name or an Array. Instead of LastRow2 use
Dim LastRow(1 to 2) as Long
LastRow(1) = Sheet1.UsedRange.Rows.count
LastRow(2) = Sheet2.UsedRange.Rows.count
Fourth why are you using
isZero = isZero*0
instead of
isZero = 0
Fifth, don't use the select() method so much. Its slow and clunky compared to just referencing the sheet you want directly
i.e. instead of doing this
LastRow = ActiveSheet.UsedRange.Rows.count
With Sheets("Sheet2").Select
LastRow2 = ActiveSheet.UsedRange.Rows.count
End With
do this instead
LastRow(1) = Sheet1.UsedRange.Rows.count
LastRow(2) = Sheet2.UsedRange.Rows.count
Sixth you don't need three separate x and i variables, you can dim them once outside of the highest For loop and reuse them for your lower For loops in the If-Else statements.