VBA Migration

Fully Qualified Enumerations

In VBA enumerations were considered to be global but in .NET they are not. This means that in .NET enumerations must be fully qualified with their full enumeration name.

Selection.Find.Wrap = Word.wdFindWrap.wdFindContinue 

Word uses loosely typed enumerations
Excel and other applications create typed enumerations which are easier to resolve.

In VBA enumeration constants could be replaced with their numerical value equivalent. This is not possible in VB.NET. Any numerical constants have to be replaced with the corresponding enumeration name. In VB.NET enumerations are classified as formal types and can therefore no longer be implicitly converted to different data types.

In VBA the only type of enumeration in Integer. In VB.NET because enumerations are actual types you must access them with the fully qualifier name of the enumeration.

No Default Properties

In VBA you could assume the default property.
In .NET you must be explicit
For example in Excel Range("B3") = "some text"
is shorthand for Range("B3").Value = "some text"
For example in Excel sMyVariable = ActiveCell
is shorthand for sMyVariable = ActiveCell.Value

For example in Word Cell(1,1).Range = "some text"
is shorthand for Cell(1,1).Range.Text = "some text"
For example in Word ActiveDocument.Sections(1).Footers(wdHeaderFooterPrimary).Range = ""
is shorthand for ActiveDocument.Sections(1).Footers(wdHeaderFooterPrimary).Range.Text = ""

This cannot be converted into a Range

CType(Application.Selection, Word.Range) 

You must refer to the Range of the Selection

CType(Application.Selection.Range, Word.Range) 

A new section will not be added.

With Application.ActiveDocument.Sections 
   .Add(.Last) 
End With 

You must refer to the Range of the Last section

With Application.ActiveDocument.Sections 
   .Add(.Last.Range) 
End With 

A new section will not be added.

objField.Code.ToString.IndexOf 

You must refer to the Text of the Code

objField.Code.Text.ToString.IndexOf 

Arrays

In VBA you can have Option Base 1
In C# (and VB.Net) this is not supported andall arrays must start at 0

Method Calls with Parentheses

Functions and subroutines require parentheses, but methods don't

Call MsgBox("My Message") 

In VBA when you use methods, spaces are required rather than parentheses

MsgBox "My Message" 

In C# parentheses are required when passing parameters to a method call

Named Ranges

You cannot use array syntax to access the named ranges

myWbk.Names.Item(rangeName) 
// the following will not work 
myWbk.Names[rangeName] 

Inconsistency - Automatic data type conversion

some data types change automatically, but others do not
The following line is fine is VBA as automatic type conversion happens automatically.

sMyVariable = txtTextBox.Text * txtAnotherTextBox.Text 

Although this is not true for all operators. The following line however will generate a compile error ?

sMyVariable = txtTextBox.Text + txtAnotherTextBox.Text 

Type conversion in this case will have to be explicit

sMyVariable = Val(txtTextBox.Text) + Val(txtAnotherTextBox.Text) 

Inconsistency - Value types without a Set keyword

Some variables have to be initialised with the Set keyword but not all of them.
The following line does not require Set

vVariable = ActiveCell 

but other variables do

Set vWsh = ActiveSheet 

Range.Value

The value of objRange.Value is Nothing when the cell is empty

Dim objRange As Excel.Range 
If objRange.Value Is Nothing Then 
   'the cell is empty
End If 

Before referring to any cell you should call the clsCell.TypeReturn function to check the contents of the cell

If clsCell.TypeReturn(objRange) = "Number" Then 
End If 

sText = (string)objCell.Value2  'this works when the cell contains text  
sText = (string)objCell.Value2.ToString()  'this works when the cell doesn't contain text 

what if the cell is empty ??

objRange.Value = arArray 

test for different size and make this bullet proof !!
what if cells are formatted as text / values etc

For Each does not work

You must use For Loop instead of For - Each for the following collections:
Workbook.Names Collection
Range.Cells Collection

The following code does not work

Dim objName As Excel.Name 
For Each objName In Workbooks.Names 
   objName = objNames.Item(inamescount) 

Next objName 

Use must use a For Loop instead

Dim objName As Excel.Name 
Dim icount As Integer 
For icount = 1 To Workbooks.Names.Count 

Next icount 

The following code does not work

Dim objCell As Excel.Cell 
For Each objCell In Range.Cells 

Next objCell 

Use must use a For Loop instead

Dim objCell As Excel.Cell 
Dim icount As Integer 
For icount = 1 To Range.Cells.Count 
   objcell = CType(objSelection.Item(icellcount), Excel.Range) 

Next icount 

Application Object

In VBA there is an implicit reference to Application
Referring to the Application object:
In Add-ins - cls1Constants.gApplication.ActiveWorkbook
In document level - Globals.ActiveWorkbook

Globals.ThisAddin.Application ?

Globals.Sheet1.Rows.getItem(12,System.Type.Missing) ?

Workbooks

Worksheets

Cells & Ranges

Colours

RGB(10,20,30) = Microsoft.VisualBasic.RGB()
Word.wdColor = (Microsoft.Office.Interop.Word.wdColor)Microsoft.VisualBasic.RGB()
Word.wdColor = Ctype(Microsoft.VisualBasic.RGB(), Microsoft.Office.Interop.Word.wdColor)

Numbers

VBA.Abs

ABS - Returns the absolute value of a number.

'VBA Code
Abs(-40) 

'C# Equivalent
System.Math.Abs(-40) 

VBA.CInt

CINT - Returns a number converted to an integer data type.

'VBA Code
CInt(0.2) 

'C# Equivalent
System.Convert.ToInt32(0.2) 

VBA.Exp

EXP - Returns the base of natural logarithm raised to a power

'VBA Code


'C# Equivalent

VBA.Hex

HEX - Returns the number converted to a hexadecimal

'VBA Code
Hex(iValue) 

'C# Equivalent
iValue.ToString("X") 

VBA.Fix

FIX - Returns the integer portion of a number.

'VBA Code


'C# Equivalent

VBA.Int

INT - Returns the number rounded down to the nearest integer.

'VBA Code
Int(0.9) = 0 

'C# Equivalent
System.Math.Floor(0.9) 

VBA.IsNumeric

ISNUMERIC - Returns the value indicating if an expression contains a number.

'VBA Code
IsNumeric(sCharacter) 

C# Equivalent, single character 
System.Char.IsNumber(sCharacter.Chars(0)) = True; 

C# Equivalent, entire string 
int integerValue; 
string stringValue = "2030"; 
bool result = int.TryParse(stringValue, out integerValue); 
if (result == true) 
{ // this string contains a valid integer 
} 

VBA.Log

LOG - Returns the natural logarithm of a number

'VBA Code


'C# Equivalent

VBA.Mod

MOD - Returns the remainder after division

'VBA Code


'C# Equivalent

VBA.Round

ROUND - Returns a number rounded to a given number of decimal places.

'VBA Code
Round(0.149,2) 

'C# Equivalent
System.Math.Round(0.149,2, MidPointRounding.AwayFromZero) 

VBA.Rnd

RND - Returns a random number between 0 and 1

'VBA Code


'C# Equivalent

VBA.Sgn

SGN - Returns the sign of a number.

'VBA Code
Sgn(1) 

'C# Equivalent
System.Math.Sign(1) 

VBA.Sqr

SQR - Returns the square root of a number.

'VBA Code
Sqr(9) 

'C# Equivalent
System.Math.Sqrt(9) 

Integer Division

C# truncates, VB.Net rounds

Dim itotal As Integer = 20; 
Dim ivalue As Integer = 3 
Dim iresult As Integer = itotal / ivalue 

int itotal = 20; 
int ivalue = 3 
int iresult = itotal / ivalue; 

VBA.Date

The DATE function returns the current system date.

'VBA Code
VBA.Date 

'C# Equivalent

VBA.DateAdd

The DATEADD function returns the date to which a specified time interval has been added.

'VBA Code
VBA.DateAdd 
Microsoft.VisualBasic.DateAndTime.DateAdd(Microsoft.VisualBasic.DateInterval.Date, _ 
                                          Number, _ 
                                          DateValue) 
Microsoft.VisualBasic.DateAndTime.DateAdd(Interval, _ 
                                          Number, _ 
                                          DateValue) 

'C# Equivalent

VBA.DateDiff

The DATEDIFF function returns the number of time intervals between two specific dates.

'VBA Code
VBA.DateDiff 
Microsoft.VisualBasic.DateAndTime.DateDiff(Microsoft.VisualBasic.DateInterval.Date, _ 
                                           Date1, _ 
                                           Date2, _ 
                                           FirstDayOfWeek, _ 
                                           FirstWeekOfYear) 
Microsoft.VisualBasic.DateAndTime.DateDiff(Interval, _ 
                                           Date1, _ 
                                           Date2, _ 
                                           FirstDayOfWeek, _ 
                                           FirstWeekOfYear) 

'C# Equivalent

VBA.DatePart

The DATEPART function returns the specified part of a given date.
This method can now take an enumerated constant as well as a string constant.

'VBA Code
VBA.DatePart 
Microsoft.VisualBasic.DateAndTime.DatePart(Microsoft.VisualBasic.DateInterval.Date, _ 
                                           Date, _ 
                                           FirstDayOfWeek, _ 
                                           FirstWeekOfYear) 
Microsoft.VisualBasic.DateAndTime.DatePart(Interval, _ 
                                           Date, _ 
                                           FirstDayOfWeek, _ 
                                           FirstWeekOfYear) 

'C# Equivalent

VBA.DateSerial

The DATESERIAL function returns the date given a year, month and day.

'VBA Code
VBA.Format(VBA.DateSerial(2010,12,1), "dd-mmm") 

'C# Equivalent
new System.DateTime(2010,12,1).ToString("dd-mmm") 

VBA.DateValue

The DATEVALUE function returns the date given a string representation of a date.

'VBA Code
VBA.Format(VBA.DateValue(2010,12,1), "dd-mmm") 

'C# Equivalent
System.Convert.ToDateTime(2010,12,1).ToString("dd-mmm") 

VBA.Day

The DAY function returns the day from a given date.

'VBA Code
VBA.Day 
Microsoft.VisualBasic.DateTime.Day 

'C# Equivalent
?? 

VBA.Format

The FORMAT function returns the text string of a number or date in a particular format.

'VBA Code
VBA.Format(VBA.Now(), "hh:mm:ss AMPM") = 10:40:17 AM 
VBA.Format("12345,"#,###.00") = 12,345.00 
VBA.Format("12345,"0.00") = 12345.00 

'C# Equivalent
System.DateTime.Now().ToString("hh:MM:ss tt") 
System.Convert.ToInt32("12345").ToString("#,###.00") 
System.Convert.ToInt32("12345").ToString("0.00") 

VBA.Hour

The HOUR function returns the hour from a given time.

'VBA Code
VBA.Hour 

'C# Equivalent
?? 

VBA.IsDate

The ISDATE function returns the value indicating if an expression is a date.

'VBA Code
If (VBA.IsDate("01/12/2014") = True) Then 

'C# Equivalent
System.DateTime temp; 
if (System.DateTime.TryParse("01/12/2014", out temp)) 

VBA.Now

The NOW function returns the current system date and time.

'VBA Code
VBA.Now 

'C# Equivalent
System.DateTime.Now 

VBA.Minute

The MINUTE function returns the minute from a given time.

'VBA Code
VBA.Minute(VBA.Time) 

'C# Equivalent
System.DateTime.Now.Minute.ToString 

VBA.Month

The MONTH function returns the month from a given date.

'VBA Code
VBA.Month 

'C# Equivalent
?? 

VBA.MonthName

The MONTHNAME function returns the month as a string.

'VBA Code
VBA.MonthName(3) 
Microsoft.VisualBasic.DateAndTime.MonthName(Month, Abbreviate) 

'C# Equivalent
System.Globalization.CultureInfo.CurrentCulture.DateTimeFormat.GetMonthName(3) 

VBA.Second

The SECOND function returns the second from a given time.

'VBA Code
VBA.Second 

'C# Equivalent

VBA.Time

The TIME function returns the current system time.

'VBA Code
VBA.Time 

'C# Equivalent
?? 

VBA.TimeSerial

The TIMESERIAL function returns the time for a specific hour, minute and second.

'VBA Code
VBA.TimeSerial 

'C# Equivalent

VBA.TimeValue

The TIMEVALUE function returns the

'VBA Code
VBA.TimeValue 

'C# Equivalent
?? 

VBA.Weekday

The WEEKDAY function returns the

'VBA Code
VBA.Weekday("01/12/2010") = 4 
Microsoft.VisualBasic.DateAndTime.WeekdayName("01/12/2014") 

'C# Equivalent
System.Convert.ToInt32(System.Convert.ToDateTime("01/12/2014").DayOfWeek).ToString(); 

VBA.WeekdayName

The WEEKDAYNAME function returns the day of the week as a string.

'VBA Code
VBA.WeekdayName(2) = Tuesday 
Microsoft.VisualBasic.DateAndTime.WeekdayName(2) 

'C# Equivalent
System.Globalization.CultureInfo.CurrentCulture.DateTimeFormat.DayNames(2).ToString(); 

VBA.Year

The YEAR function returns the year from a given time.

'VBA Code
VBA.Year 

'C# Equivalent
System.DateTime.Year 

Implicit Date Operations

When working with Dates in Excel it is important to know the differences between VBA and .NET
In VBA you can use dates and times as "real" dates and times

#1/4/2007# 

or you can use them as date serial numbers

36282.5 

Explicit Date Operations

In .NET you will have to convert these dates explicitly.
There are two different ways of doing these conversions

Dim dbMyDate As Double 
dbDate = Now().ToOADate 
dbDate = System.DateTime.ToOADate(Now()) 

It is a similar story for dates that are supplied as strings
You should use the Parse method to convert a string to a date

Dim dbMyDate As Double 
dbMyDate = System.DateTime.Parse("01 Jan 2008") 

In VBA dates are stored internally as a serial value ( the number of days since Dec 30 1899)
in VBA times are stored as fractions.
In VBA dates are stored as a floating-point number and are represented as Doubles.

In VB.NET dates and times are stored completely differently.
In .NET a date maps to a System.DateTime

Converting VBA Doubles into .NET DateTimes

To convert between a VBA Double data type and a .NET DateTime data type you can use the following:
You should use the DateTime's ToOADate and FromOADate methods.

Dim myDate As DateTime 
myDate = Date.FromOaDate(Globals.Sheet1.Range("A1").Value2 

Dates and DateTime

Range["A1"].Value = "08/11/04" 

This value could be interpreted as any of the following dates depending on the locale of the current thread
     ● August 11, 2004
     ● November 8, 2004
     ● November 4, 2008

The workaround is to never pass dates as literal strings into Excel.
Always construct a date using the System.DateTime object and pass it to Excel using the DateTime.ToOADate method
The ToOADate method converts a DateTime to an OLE Automation date which is the date format used by Excel.

System.DateTime odate = new System.DateTime(2014,4,11); 
range1.Value = odate.ToOADate(); 

Excel calculates the number of days elapsed since 31 December 1899
.NET calculates the number of days elapsed since 1 January 1900
To convert an Excel date in 1900 that is earlier than 1 March 1900 into a DateTime object you must add one day

Excel cannot represent days before 1 January 1900 or (I January 1904) so when converting a DateTime into an Excel date, you have to pass a string rather than a number representing the date.

Strings & Characters

VBA.Asc

ASC - Returns the ANSI number for the first character in a text string.

'VBA Code
Dim sngValue As Single 
sngValue = VBA.Asc("A")    '=65  

'C# Equivalent
Single sngValue; 
char tempCharacter = "A"c; 
char[] getCharacters = tempCharacter; 
char convertCharacter = System.Text.ASCIIEncoding.ASCII.GetBytes(getCharacters)[0]; 
sngValue = System.Convert.ToSingle(convertCharacter); 

'VBA Code
Dim sngValue As Single 
sngValue = VBA.Asc("Asometext")  '=65  

'C# Equivalent
string tempString = "Asometext"; 
Single sngValue; 
char[] getCharacters = tempString.ToCharArray(); 
char convertCharacter = (char)System.Text.ASCIIEncoding.ASCII.GetBytes(getCharacters)[0]; 
sngValue = System.Convert.ToSingle(convertCharacter); 

VBA.Chr

CHR - Returns the character with the corresponding ANSI number.

'VBA Code
VBA.Chr(65) = "A" 

'C# Equivalent
System.Convert.ToChar(65) = "A" 

VBA.InStr

INSTR - Returns the position of a substring within a larger string.
In VBA, Instr() returns 1 when the find item is at the start of the string and is also case sensitive
In VSTO, sText.IndexOf() returns 0 when the find item is at the start of the string and is also case sensitive

'VBA Code
If VBA.Instr(sVariable, "find this") > 0 Then 

'C# Equivalent
if sVariable.IndexOf("find this") > -1 { } 

'VBA Code
If VBA.Instr(1,sVariable,"find this") > 0 Then 

'C# Equivalent
if sVariable.IndexOf("find this",0) > -1 { } 

'VBA Code
If VBA.Instr(----) > 0 Then 

'C# Equivalent
If (sText.IndexOf(-----) > -1) Then 

For more details, please refer to the Strings & Characters > Finding

VBA.InStrRev

INSTRREV - Returns the position of a substring within a larger string, from the end.

'VBA Code
VBA.InstrRev(sVariable, "find this", Len(sVariable) ) 

'C# Equivalent
sVariable.Reverse.IndexOf("find this", 0) - check this !!! 

'VBA Code
Do While VBA.InstrRev(---) 
Loop 

'C# Equivalent
while sText.IndexOf(---) > -1 
{ 
} 

VBA.LCase

LCASE - Returns the text string with all characters converted to lowercase.

'VBA Code
VBA.LCase(sVariable) 
VBA.LCase("LOWERCASE") 

'C# Equivalent
sVariable.ToLower 
String.Copy("LOWERCASE").ToLower() 

VBA.Left

LEFT - Returns a number of characters from the left of a string.

'VBA Code = C# Equivalent
VBA.Left(sVariable,4) = sVariable.Substring(0,4) 

'VBA Code - First 4 characters
VBA.Left(sVariable,4) 

'C# Equivalent
sVariable.Substring(0,4) 

'VBA Code - Remove the last character
Dim sText As String = "some text" 
VBA.Left(sText, Len(sText) - 1) 

'C# Equivalent
sText.Substring(0,sText.Length - 1) = "some tex" 

VBA.Len

LEN - Returns the number of characters in a string.

'VBA Code
VBA.Len(sVariable) 

'C# Equivalent
sVariable.Length 

'VBA Code
VBA.Len("my string") 

'C# Equivalent
sVariable = "my string" 
sVariable.Length 

VBA.Mid

MID - Returns the text string which is a substring of a larger string.

'VBA Code = C# Equivalent
VBA.Mid(sVariable,Len(sVariable),1) = sVariable.Substring(sVariable.Length - 1,1) 
VBA.Mid(sVariable,Len(sVariable),1) = sVariable.Substring(sVariable.Length - 1) 
VBA.Mid(sVariable,Len(sVariable)) = sVariable.Substring(sVariable.Length - 1) 

VBA.Mid(sVariable,Len(sVariable),1) = sVariable.Substring(sVariable.Length - 1,1) 
VBA.Mid(sVariable,Len(sVariable) - 1,1) = sVariable.Substring(sVariable.Length - 2,1) 
VBA.Mid(sVariable,Len(sVariable) - 2,1) = sVariable.Substring(sVariable.Length - 3,1) 

'VBA Code - return the first character
VBA.Mid(sVariable,1,1) 

'C# Equivalent
sVariable.Substring(0,1) 

'VBA Code - return the second character
VBA.Mid(sVariable,2,1) 

'C# Equivalent
sVariable.Substring(1,1) 

VBA.Right

RIGHT - Returns the number of characters from the right of a text string.

'VBA Code = C# Equivalent
VBA.Right(sVariable,1) = sVariable.Substring(sVariable.Length - 1) 
VBA.Right(sVariable,2) = sVariable.Substring(sVariable.Length - 2) 

VBA.Right(sVariable,Len(sVariable),1) = sVariable.Substring(sVariable.Length - 1,1) 
VBA.Right(sVariable,Len(sVariable),1) = sVariable.Substring(sVariable.Length - 1) 

VBA.Right(sVariable,Len(sVariable) - 1) = sVariable.Substring(sVariable.Length - 2) 
VBA.Right(sVariable,Len(sVariable) - 5) = sVariable.Substring(sVariable.Length - 6) 

'VBA Code - Check the last 4 characters
If (VBA.Right(sVariable,4) = "Text") Then 

'C# Equivalent
if (sVariable.EndsWith("Text") = True) 

'VBA Code - Return the last character
Dim sText As String = "some text" 
VBA.Right(sText,1) 

'C# Equivalent
sText.Substring(sText.Length - 1) = "t" 

VBA.Space

SPACE - Returns the specified number of spaces.

'VBA Code
Select Case sCountry & Space(20 - Len(sCountry)) 
   Case "England             " : Call Something 
   Case "Germany             " : Call Something 
   Case "France              " : Call Something 
End Select 

'C# Equivalent
switch (sCountry.PadRight(20)) 
{ 
   case "England             " : Call Something 
   case "Germany             " : Call Something 
   case "France              " : Call Something 
} 

'VBA Code
sValue = Space(5) & "name" 

'C# Equivalent
sValue = String.Empty.PadLeft(5) + "name" 

VBA.Split

SPLIT - Returns the array containing a specified number of substrings.

'VBA Code
Dim sStringConCat As String 
Dim sValues As Variant 
sStringConcat = "one,two,three,four" 
sValues = VBA.Split(sStringConCat, ",") 

'C# Equivalent
string sStringConCat; 
string[] sValues; 
sStringConcat = "one,two,three,four"; 
sValues = sStringConcat.Split(","); 
sValues = sStringConcat.Split(sDeimiter.ToCharArray()); 

VBA.Replace

REPLACE - Returns the text string with a number of characters replaced

'VBA Code
Dim sValue As String 
sValue = "this is the old text" 
VBA.Replace(sValue,"old text","new text") = "this is the new text" 

'C# Equivalent
string sValue 
sValue = "this is the old text"; 
sValue.Replace("old text","new text") = this is the new text" 

VBA.UCase

UCASE - Returns the text string with all the characters converted to uppercase.

'VBA Code
VBA.UCase(sVariable) 

'C# Equivalent
sVariable.ToUpper(); 

VBA.Val

VAL - Returns the numbers contained in a string as a numeric value of the appropriate data type.

'VBA Code
VBA.Val(sVariable) 

'C# Equivalent
System.Int32.TryParse(sVariable, out iValue); 

No Fixed Length Strings

In VBA if you assign text that is longer than a fixed length string it is just truncated (?)
IN VB.Net fixed length strings are not supported.

Functions for Bytes / Double Bytes

All the string functions for handling bytes and double bytes in VBA have been removed in VB.NET
In VB.Net all strings are unicode, so converting strings to double-byte character sets is no longer necessary.

Files & Directories

In VB.Net you can read and write from a text stream using the StreamReader or StreamWriter objects.
There are also BinaryReader and BinaryWriter objects for binary data.
The StreamReader and StreamWriter objects work either with a filename string or a FileStream object.
The FileStream class provides random access to a disk file and allows you to specify whether you want to create or open a file.

Scripting.Dictionary

The closest equivalent to this in .NET is a System.Collections.Serialized.StringDictionary ??
Keys.CopyTo ??

Windows Forms

VBA Forms cannot be copied or imported into Visual Studio
Forms in VBA are based on the MSForms type library.
Forms in VBA have been replaced with Windows Forms
In most cases Userforms will need to be recreated as Windows Forms.

Instance vs Actual Object

In .NET forms are treated as classes and there is no ambiguity between instances and the actual class itself.
In VBA the correct way to display a userform is to first create an instance and then refer to that instance.

Dim myUserform As New Userform1 
Load myUserform 
myUserform.Show 

However in VBA it is possible to have the following line

Load Userform1 
Userform1.Show 

In this case the default instance would be used.
Here there is a mix up between the userform object (or instance) and the actual class itself

In .NET we have a New constructor method and a Dispose method for any cleanup

VBA userform - Form_Unload ??

Application.DoEvents

System.Windows.Forms.Application.DoEvents 

Modal vs Modeless

VBA userforms are modal by default.
In .NET windows forms are modeless by default

This is the preferred method

Dim myUserform As New Userform1 
Userform1.Show 

The following would also work but not as common

Dim myUserform As Userform1 = New Userform1 
Userform1.Show 

Show vs ShowDialog

.Show - displays a modeless form
.ShowDialog - displays a modal form

Userform_Terminate

Events

VBA userforms have 23 different events
Windows Forms have 83 different events

Validating event associated with all controls ?
"LostFocus" ??

ToolTips

In the section "Common Controls" there is Tooltip control.
There is no ToolTipText property associated with any of the controls.
Drag this control to your form and it will show up below the form.
This control can then be used to associated a tooltip with another control.

Keystrokes

It is possible to monitor the user's keystrokes while working in a windows form.
Set the Form's Keypreview property to True

Form_KeyUp
Form_KeyDown
Form_Keypress

Different Controls

Several controls have had their names changes and also some properties and methods have changed.

Different Properties

Controls that cannot be added to VSTO Excel workbooks or VSTO Word documents

A number of windows form controls cannot be added to your workbook or document

Locale / Culture

Visual Studio 2008 and Earlier

When programming against Excel using managed code you could get certain methods and properties behaving differently depending on the locale of the current thread.
This problem only occurs in COM Add-ins, Automation add-ins and Automation executables.
This problem did not occur in document level solutions or add-ins built using VSTO.
If you want to define a formula for a Range and you are in the french locale you must use localised french formula names.

Range["A1"].Formula = "SOMME(3;4)"; 

Excel expects localized strings for date formats, number formats and formula names.

You could get around this issue by accessing these properties using reflection.
Reflection enables you to specify an English locale and write code that will work regardless.

Excel.Range range1 = sheet.Range["A1"]; 
typeof(Excel.Range).InvokeMember("Formula", 
                System.Reflection.BindingFlags.Public | 
                System.Reflection.BindingFlags.Instance | 
                System.Reflection.BindingFlags.SetProperty, 
                null, range1, 
                new object[]{"=SUM(10,20)"}, 
                System.Globalization.CultureInfo.GetCultureInfo(1033)); 

VSTO Solutions

VSTO solutions solve this locale problem by using a transparent proxy that sits between Excel and VSTO.
This proxy forces a US English locale which matches the behaviour in VBA.
A new attribute was added to the AssemblyInfo.cs file to resolve this issue.
The default value for this attribute is true.
This transparent proxy can:
     ● slow the code slightly
     ● cause objects to look slightly different in the debugger
This proxy was removed in .NET 4.0
You can bypass this proxy by setting the assenbly level attribute ExcelLocale1033 to false in AssemblyInfo.cs

[assembly: ExcelLocale1033(false)] 

Or alternatively if you only want to bypass for a particular method you can use:
Microsoft.Office.Tools.Excel.ExcelLocale1033Proxy.UnWrap method
This method returns the raw PIA object which exposes you to the locale issue.

Handle Culture Issues

CultureInfo baseCulture = System.Threading.Thread.CurrentThread.CurrentCulture; 
Thread.CurrentThread.CurrentCulture = new CultureInfo(xlapp.LanguageSettings.LanguageID(Office.MsoAppLanguageID.msoLanguageIDUI)); 
// do something 
System.Threading.Thread.CurrentThread.CurrentCulture = baseCulture;