1. IENG 490 LAB FIND/FINDNEXT AND BYREF/BYVAL
RESEARCH ASSISTANT: ADEWALE ADESINA

2. Find functions Generally, each of the function is expressed as
.Find( What , After , LookIn , LookAt , SearchOrder , SearchDirection , MatchCase , MatchByte , SearchFormat )
Take note of the “dot” before “Find”, the meaning of this is that you will have to find something from somewhere.

3. That “Somewhere” is written before the “dot”.
Ofcourse “Somewhere” to find a string or any Excel data type must be a collection of strings or other data types which is or must be definate.
That is, it should have a specified boundaries (starting point and end point).
Obviously, find function anticipates to look (in, at), after, search (order or with direction or certain format), match data (by case or character, byte) from a range of string of data type.
Hence a range of data source must be specified with find function and a Range object represents the first cell where that information is found.

4. Hence a range of data source must be specified with find function and a Range object represents the first cell where that information is found.
The decleration is
Range.Find(Requiredfunction:=string/datatype,Optionalfunction:=excelValues)

5. The FindAll function simplifies the use of the Find method.
Function FindAll(What, Optional SearchWhat As Variant, _
        Optional LookIn, _
        Optional LookAt, _
        Optional SearchOrder, _
        Optional SearchDirection As XlSearchDirection = xlNext, _
        Optional MatchCase As Boolean = False, _
        Optional MatchByte, _
        Optional SearchFormat) As Range
The function returns a range consisting of all the cells that match the specified criteria. 
The table below presents the list of the required and optional functions

9. Sub Find( )
Dim SalaryWkSht As Worksheet
Dim LastRow As Long, i As Long, c As Long
Dim myCell As Range
Set SalaryWkSht = Sheets("Sheet1")
LastRow = SalaryWkSht.Range("A" & Rows.Count).End(xlUp).Row
c = 12000
Set myCell = SalaryWkSht.Range("B1:B" & LastRow).Find(What:=c, LookIn:=xlValues)
If Not myCell Is Nothing Then
MsgBox "Value found in cell " & myCell.Address
End If
Exit Sub
End Sub

12. Assumming the value to be found appears more than once in the cell, we need .FindNext function to find them within the cell.
Sub FindNext()
Dim c As Range
On Error Resume Next
With Worksheets(1).Range("B1:B500")
Set c = .Find(10000, LookIn:=xlValues)
If Not c Is Nothing Then
firstaddress = c.Address Do
MsgBox "Value found in cell " & c.Address
Set c = .FindNext(c)
Loop While Not c Is Nothing And c.Address <> firstaddress
End If
End With
End Sub

15. ByVal and ByRef Function
A previously declared argument can by passed over or copied to another argument(s) by using By Value (ByVal) or By Reference (ByRef) Subfunction.
ByRef passes a pointer to the variable, so any changes are reflected everywhere that variable is used.
ByVal means that you are passing a copy of a variable to your Subroutine. Changes are made to the copy but the original will not be altered.

16. This implies that , in the case of objects, they are always passed as references (pointers) but if you pass an object ByVal you pass a copy of the pointer to the object rather than the original pointer (note: not a copy of the object)
ByVal
Public Function functionByVal(ByVal x)
variant/datatype
functionByVal = variant/datatype
End Function
ByRef
Public Function functionByRef(ByRef x)
functionByRef = variant/datatype

17. Default argument
Public Function functionByDefault(x)
variant/datatype
functionByDefault= variant/datatype
End Function
It should be noted that whenever, the default argument is used, ByRef is preset by the Excel VBA.

18. Example: Datatype
Sub ieng490( ) Dim i As Long i = 1 Call Change_ByRef(i) ' i is changed by the Change_ByRef procedure and that change IS reflected here too because it was passed by reference MsgBox "i is now: " & i
End Sub Sub Change_ByRef(ByRef lInput As Long) lInput = 14 End Sub

21. Sub ieng490ByVal ( ) Dim i As Long i = 1 Call Change_ByVal(i) ' i is changed only within the Change_ByVal procedure because a COPY of it was passed MsgBox "i is still: " & i End Sub Sub Change_ByVal(ByVal lInput As Long) lInput = 21 End Sub

24. Example: Object Sub Object_ieng490ByRef ( ) Dim j As Range
Set j = Range("B1")
Call Change_object_ByRef(j)
' j is changed to a different cell by the Change_ByRef procedure and
' that change IS reflected here too because it was passed by reference
MsgBox "j is now: " & j.Address
End Sub
Sub Change_object_ByRef(ByRef jInput As Range)
' change the range variable to one row down
Set jInput = jInput.Offset(1)

27. Sub Object_ieng490ByVal ( ) Dim j As Range Set j = Range("B1")
Call Change_object_ByVal(j) ' r is changed to a different cell by the Change_ByVal procedure but ' that change IS NOT reflected here because it was passed by value. MsgBox "j is still: " & j.Address End Sub
Sub Change_object_ByVal(ByVal jInput As Range) ' change the range variable to one row down Set jInput = jInput.Offset(1) End Sub

30. Data ByRef
Sub MyHome ( )
Dim x As Double
x = 5.005
MsgBox AddUp(x)
End Sub
Function AddUp(ByRef x As Double) As Double
x = 10 + x
End Function

32. Example 2: Data ByVal
Sub MyHome( )
Dim x As Double
x = 5.005
MsgBox AddUp(x)
MsgBox x
End Sub
Function AddUp(ByVal x As Double) As Double
AddUp = 10 + x
End Function

35. CIRCLE RADIUS, AREA AND CIRCUMFERENCE Sub CalRadiusByRef()
Dim r As Double
r = 2.5
Radius = r
MsgBox "Radius of the circle is " & r
MsgBox "Area of the circle is " & Area(r)
MsgBox "Circumference of the circle is " & Circumference(r)
End Sub
Function Area(Radius As Double) As Double
Radius = Radius ^ 2
Area = WorksheetFunction.Pi * Radius
End Function
Function Circumference(Radius As Double) As Double
Circumference = 2 * WorksheetFunction.Pi * Radius
End Function 

38. To correct this, ByVal can be added the Function Area code as
You will notice that the value of the circumference of obtained by the ByRef function is wrong
The actual value for the circumference of a circle with radius of 2.5 is 15.7
This is as a result of ByRef function that changed the value of the original radius to the new value of radius used for the calculation of the area at this line
  Radius = Radius ^ 2
To correct this, ByVal can be added the Function Area code as
“Function Area(ByVal Radius As Double) As Double”

39. Sub CalRadius()
Dim r As Double
r = 2.5
MsgBox "Radius of the circle is " & r
MsgBox "Area of the circle is " & Area(r)
MsgBox "Circumference of the circle is " & Circumference(r)
End Sub
Function Area(ByVal Radius As Double) As Double
Radius = Radius ^ 2
Area = WorksheetFunction.Pi * Radius
End Function
Function Circumference(Radius As Double) As Double
Circumference = 2 * WorksheetFunction.Pi * Radius