TOP Excel VBA Interview Questions and Answers
What is the difference between ByVal and ByRef and which is default?
ByRef: If you pass an argument by reference when calling a procedure the procedure access to the actual variable in memory. As a result the variable’s value can be changed by the procedure.
ByVal: If you pass an argument by value when calling a procedure the variable’s value can be changed with in the procedure only outside the actual value of the variable is retained.
ByRef is default: Passing by reference is the default in VBA. If you do not explicitly specify to pass an argument by value VBA will pass it by reference.
What is the meaning of Option Explicit and Option Base?
Option Explicit makes the declaration of Variables Mandatory while Option Base used at module level to declare the default lower bound for array subscripts. For eg. Option Base 1 will make the array lower bound as 1 instead of 0.
What are various data type and their size?
i) The Boolean data type has only two states, True and False. These types of variables are stored as 16-bit (2 Byte) numbers, and are usually used for flags.
ii) The Byte data type is an 8-bit variable which can store value from 0 to 255.
iii) The Double data type is a 64-bit floating point number used when high accuracy is needed.
iv) The Integer data type is a 16-bit number which can range from -32768 to 32767. Integers should be used when you are working with values that can not contain fractional numbers. In case, you’re working over 32767 rows use Long as data type.
v) The Long data type is a 32-bit number which can range from -2,147,483,648 to 2,147,483,647.
vi) The Single data type is a 32-bit number ranging from -3.402823e38 to -1.401298e-45 for negative values and from 1.401298e-45 to 3.402823e38 for positive values. When you need fractional numbers within this range, this is the data type to use.
vii) The String data type is usually used as a variable-length type of variable. A variable-length string can contain up to approximately 2 billion characters. Each character has a value ranging from 0 to 255 based on the ASCII character set.
Difference between ActiveWorkbook and ThisWorkbook.
ThisWorkbook refers to the workbook where code is being written while ActiveWorkbook refers to the workbook which is in active state with active window. In case of only one workbook open, ActiveWorkbook is same as ThisWorkbook.
Code to find a Last used Row in a column or Last used column of a Row.
Last Row in a column can be find using End(xlUp) and Last Column in a row can be find using End(xlToLeft). For e.g. Range(“A1048576”).End(xlUp).Row gives last used row of Column A.
Difference between ActiveX and Form Controls.
i) Forms controls can be used on worksheets and chart sheets. Forms controls can also be placed within embedded charts in Classic Excel (though not in Excel 2007). ActiveX controls can only be used on worksheets. ActiveX controls do not work in MacExcel.
ii) The Forms controls aren’t very complicated, and they have been part of Excel for longer (they were used in Excel 5/95’s dialog sheets) than the Controls Toolbox (Excel 97), so it stands to reason that they’d be more seamlessly integrated. Being newer, the ActiveX controls have richer formatting possibilities. Both can link to cells and ranges in the worksheet.
What is the difference b/w Functions and Subroutines?
i) Subroutines never return a value but functions does return values.
ii) A function could not change the values of actual arguments whereas a subroutine could change them.
How to debug a VBA code?
Using Breakpoints(F9), Step-by-step execution (F8), Debug.Print & Immediate Window and Watch window.
Draw basic Excel Object Model.
Application –> Workbooks –> Worksheets –> Range / Chart
What are properties, methods, events and objects?
For details click here –> http://msdn.microsoft.com/en-us/library/ms172576%28VS.80%29.aspx
All the controls in the ToolBox except the Pointer are objects in Visual Basic. These objects have associated properties, methods and events.
A property is a named attribute of a programming object. Properties define the characteristics of an object such as Size, Color etc. or sometimes the way in which it behaves.
A method is an action that can be performed on objects. For example, a cat is an object. Its properties might include long white hair, blue eyes, 3 pounds weight etc. A complete definition of cat must only encompass on its looks, but should also include a complete itemization of its activities. Therefore, a cat’s methods might be move, jump, play, breath etc.
Visual Basic programs are built around events. Events are various things that can happen in a program. Let us consider a TextBox control and a few of its associated events to understand the concept of event driven programming. The TextBox control supports various events such as Change, Click, MouseMove and many more that will be listed in the Properties dropdown list in the code window for the TextBox control. We will look into a few of them as given below.
* The code entered in the Change event fires when there is a change in the contents of the TextBox
* The Click event fires when the TextBox control is clicked.
* The MouseMove event fires when the mouse is moved over the TextBox
How to hide a worksheet so that a user cannot unhide it?
Use Sheet’s visible property and set it to xlSheetVeryHidden . For eg. Sheets(1).Visible = xlSheetVeryHidden will super hide the first worksheet of the workbook.
Union is used for _____________ ?
To unite the different ranges depending on the logic. It is similar to set union, here range works as set. For eg. Set nrange = Union(rng1,rng2)
Which are the 2 macro languages and which do you use ?
XLM (used in Excel 97 or before) and VBA(used for 2000 and after). Obviously, VBA is in use these days.
Can you lock cells such that only specific users can modify them?
There is a option “Allow users to edit ranges” can be used for this purpose.
How can you add a drop-down list to a cell so the user can choose a value from the list?
Using ‘Data Validation’.
How can you increase the number of rows in a worksheet?
No one can’t. They’re fixed as 65536(2^16) in Excel 2003 or before and 1048576(2^20) in Excel 2007 & Excel 2010.
How can you increase the number of columns in a worksheet?
No one can’t. They’re fixed as 256(2^8) in Excel 2003 or before and 16384(2^14) in Excel 2007 & Excel 2010.
How will you distribute a workbook such that it can’t be copied using macro or anything?
We can create a workbook which cannot be modified but can not create a workbook which can’t be copied.(It depends on system security, it has nothing to do with Excel or VBA)
Your colleague created a dashboard and when you enter a value, it appears with two decimal places. For example, when you enter 265 it shows up as 2.65. What’s wrong?
By chance Excel’s fixed-decimal mode was turned on. To return to normal,
Excel 2003 –>
Click Tools and then Options to display the Options dialog box.
Then click the Edit tab and remove the check mark from the “Fixed decimal ” option.
Excel 2007 –>
Click Office button on Top-Left corner and click ‘Excel Options’.
Go to Advanced and Uncheck ‘Automatically insert a decimal point’ option.
Excel 2010 –>
Click File button on Top-Left corner and click ‘Excel Options’.
Go to Advanced and Uncheck ‘Automatically insert a decimal point’ option.
Of course, this feature can be useful when entering some types of data, but most of the time, you’ll want to keep the fixed-decimal mode turned off.