Choosing the right data structures as we plan our program is especially important. Molding our data to be structured to our specific requirements makes our program more readable, maintainable, and efficient. What can we do beyond integer, string, and date?

In my last week’s Blog post I elaborated on data types and their use in VBA.

Beyond using the readily available native data types we’re all familiar with, such as Integer, Date, String and Boolean, we can define our own, user-defined data type.

What is a User-Defined Data Type?

Simply put, a user-defined data type is a group...

Why do we need to declare data types for our variables, what purpose does it serve? * Why do some programming languages not care about it too much and what data type are available for us in VBA?

What are data types?

A data type is a structure to store data with given attributes and constraints.

You are probably familiar with some popular data types defined for us in VBA, such as an Integer, String and Date.

An Integer in VBA, for example, is allocated with 2 bytes to store numbers in the range -32,768 to 32,767.

A Date in VBA is allocated with 8 bytes to store numbers representing date and...

A collection of variables of the same data type is a very efficient data structure and easy to work with. Did you know that you can also define your own custom collections? Here is how!

What is a collection?

A collection is a stack of objects of the same type, “chained” one after the other.

As you add an object to the collection, it assumes the next index in sequence – added as the next “link” in the “chain”.

The collection is an easy to use data structure. It requires no declaration of the anticipated size of the “chain” in advance....

Leveraging the nature of numbers storage in memory, we can exploit enumerators to construct complex Boolean expressions in near-English language. This post will change the way you handle multiple-choice questions.

Last week we introduced Enumerations and how they make our lives easier when handling numeric sets of constants.

Today we’ll take it further by exploiting the Enumeration data structure to handle combinations of values.

What is Combination of Values?

The typical use case we’re addressing here, is when we have to handle multiple-choice variables that can hold any...

Instead of remembering numeric codes – label them with meaningful words. This way your code will flow from your fingers just as you speak, and your program will be clear and readable. Let us understand enumerations.

What are Enumerations?

Simply put, enumeration is about naming sets of related constant numbers.

You probably already worked with enumerations. For example, the Application.Calculation property is numeric. It holds a number representing the calculation mode of Excel. Possible values for this property are:

Prompt the user for required input, using an easy to interact with input box in your Excel VBA program. All you need to know about the InputBox function is right here. Oh, do not forget to validate!

What is an InputBox and When to Use It

In last week’s Blog post I covered in great detail the Excel VBA MsgBox function. I will not repeat how user interaction is incredibly important, but as you now know how to present informative messages to your user, sometimes you also need some input from the user to feed your program.

As you probably know, you can employ VBA User Forms for highly...

Show informative, easy to interact with messages to your Excel VBA program users. All you need to know about the MsgBox function is right here. Read on...

User interaction is a big deal

Why?

Because this is where your program meets the psyche, mindset, values, thoughts and habits of the user. Can you guess what those are?

If the user doesn’t feel “at home” with your application, he would not want to use it. The American science fiction writer, Larry Niven, captured the importance of the user experience beautifully:

“That's the thing about people who think they hate...

In this Blog post I cover all ways and tips for using color codes in your Excel VBA program. Discover how to store colors as constants, identify the code of any color and apply colors to any Excel object.

Understanding Color Codes

Every color is identified by a unique number. For example, 255 represents Red. 16774980 represent a specific cyan.

You can also convert any decimal number to its Hexadecimal representation (or Hex for short). For example, that cyan color number equals FFF744 in Hex representation (use any decimal to hex converter you find on the web to see how it works).

You can...

In this advanced chapter of OOP with Excel VBA, we implement objects composition with a dynamic collection in Excel VBA using Class Modules. Not for the faint of heart…

In Part 1 on this exercise of implementing OOP in Excel VBA, we left off with a half-baked order object. It had some properties and a couple of methods, but its line-items were missing.

Today we’re going to round up our order object to include its line-items.

Thinking about the right structure and arrangement of the line-items within the order object, two main characteristics should guide our thinking:

1. An order...

Ever wanted a concise, clear with code examples guide to implement OOP in Excel VBA? It is your lucky day. Read on…

After we covered in detail what OOP is in last week’s Blog post, we’re ready to see how this works in Excel VBA.

Keep your eyes on the Object

The key concept to keep in mind as we implement objects in Excel VBA, is that we are creating our own custom objects, on top of the available objects at our disposal out of the box.

The image here shows a list of the available properties and methods of the Workbook object.

This list is the exposed interface of the...