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

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.

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.

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)

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

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

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

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.

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

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.

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  

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  

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)  

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  

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

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

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   

To correct this, ByVal can be added the Function Area code as You will notice that the value of the circumference of 39.2669 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”  

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