Lua String Tutorial – Complete Guide

Have you ever wondered how games create sophisticated dialogues, generate unique codes, or manipulate text-based data? If so, you’re about to uncover the secrets of handling text and strings in the world of games and coding! Welcome to our deep dive into one of the most crucial aspects of programming and game development – the amazing world of Lua strings.

What are Lua Strings?

Strings in Lua are series of characters or a sequence of bytes representing text or other data. This all-important data type forms the very basis of games and programming.

The Game-Changing Role of Lua Strings

From storing player names to generating in-game messages, Lua strings pave the way for interactive and personalized gaming experiences. They are critical to enhancing game mechanics and creating engaging scenarios for players to navigate.

Why Learn Lua Strings?

Understanding and mastering Lua strings brings you one step closer to becoming a pro game developer, as they are not only used in game development, but are also widely used in web applications, software testing, and data analysis. The better you are with Lua strings, the more power you have to control and modify your game or application.

CTA Small Image

Basic Manipulations with Lua Strings

Let’s kick things off with some basic manipulations that you can perform with Lua strings. We will look at string creation, finding string length, and string concatenation.

Creating and Displaying a String

Creating a string in Lua is simple. All you need to do is assign a sequence of characters to a variable.

local myString = "Hello, Zenva Academy!"

Finding String Length

To get the length of a string, you use the hash sign ‘#’.

local myString = "Hello, Zenva Academy!"

String Concatenation

In Lua, you can join two or more strings into one using the ‘ ..’ operator.

local string1 = "Hello, "
local string2 = "Zenva Academy!"
local finalString = string1 .. string2

String Formatting

Lua’s string.format() function allows you to do some pretty neat stuff, like produce a string with embedded values.

local playerName = "Zenva"
local playerScore = 5000
local scoreString = string.format("%s has a score of %d", playerName, playerScore)

This is a brief overview of how to manipulate Lua strings. In the next section, we will dive into the more advanced operations.

Advanced Lua String Operations

Let’s delve into some more advanced operations on Lua strings, such as substring extraction, string pattern matching, and ASCII value conversion.

Extracting Substrings

In Lua, you can extract a substring from a parent string using the string.sub() function. The function parameters define the start and end indices of the substring.

local myString = "Hello, Zenva Academy!"
local substring = string.sub(myString, 8, 13)
print(substring) -- outputs "Zenva"

String Pattern Matching

Pattern matching is a powerful tool in Lua. Instead of using complex regular expressions, Lua uses simpler patterns for string manipulation.

local myString = "Hello, Zenva Academy! Welcome to Lua Strings."
local match = string.match(myString, "Zenva Academy")
print(match) -- outputs "Zenva Academy"

Replacing Strings

To replace part of a string in Lua, you use the gsub() function. Here is an example.

local myString = "Hello, Zenva Academy!"
local newString = string.gsub(myString, "Zenva", "Gamdev")
print(newString) -- outputs "Hello, Gamedev Academy!"

ASCII Value Conversion

The functions string.byte() and string.char() allows you to work with the ASCII values of characters.

local myString = "Z"
print(string.byte(myString)) -- outputs ASCII value of "Z"
print(string.char(90)) -- outputs "Z"

By now, you should be comfortable with the basics and some advanced operations of Lua strings. All these manipulations give you more control over text handling, which will inevitably uplift the standard of your game or application.

Case Conversion and String Replication

There will be times in game development when you need to change the case of your strings or replicate a string multiple times. Lua offers concise solutions to these needs.

Lowercase and Uppercase Conversion

To convert a string to lowercase or uppercase, you can use the string.lower() and string.upper() functions respectively.

local myString = "Hello, Zenva Academy!"
print(string.lower(myString)) -- outputs "hello, zenva academy!"
print(string.upper(myString)) -- outputs "HELLO, ZENVA ACADEMY!"

String Replication

To repeat a string multiple times, Lua provides the string.rep() function. For example:

local myString = "Zenva"
print(string.rep(myString, 3)) -- outputs "ZenvaZenvaZenva"

String Insertion

Enhancing our abilities with string manipulation, we can insert a string into another at a specified position using Lua’s table and string functions in tandem.

function insertString(parent, insert, position)
    local t = {parent:sub(1, position - 1), insert, parent:sub(position)}
    return table.concat(t)
local myString = "Hello, Zenva Academy!"
print(insertString(myString, "Gamedev ", 8)) -- outputs "Hello, Gamedev Zenva Academy!"

Trimming Whitespace

Another practical thing we sometimes need to do is trim white spaces at the beginning or end of a string. For this operation, we’ll have to use Lua’s pattern matching capabilities.

function trimString(s)
   return s:gsub("^%s+", ""):gsub("%s+$", "")
local myString = "   Hello, Zenva Academy!   "
print(trimString(myString)) -- outputs "Hello, Zenva Academy!"

These are some of the more advanced manipulations you can perform with strings in Lua. Together with the basics covered earlier in this guide, they will form a solid foundation as you explore the rest of the game development landscape with Lua.

Where to Go Next

Well done, you’ve made solid progress with your journey into strings in Lua and game development! Grasping the fundamentals and mastering the different ways to manipulate strings is a stepping stone to creating enthralling games and powerful applications.

But don’t stop here. Level up your game development skills with our Roblox Game Development Mini-Degree. This comprehensive collection of courses covers everything from Roblox basics to scripting and creating popular game types such as melee battle games and first-person shooter games. Armed with the knowledge from these courses, learners can prepare themselves for a promising career in game development.

In addition to the Mini-Degree, Zenva Academy offers a wider range of Roblox courses for those looking to broaden their skills in the Roblox universe. Dive in, challenge yourself and remember, with Zenva, you can go from beginner to professional in no time. Happy coding!


In this adventurous journey into Lua strings, we’ve unlocked the power of text manipulation, explored the essential role of strings in the world of game development, and taken a peek into the programming toolkit that makes immersive and interactive gaming experiences possible. With these newly-acquired skills, you’re ready to create, innovate and transform your gaming ideas into reality.

But as we always emphasize, learning is a continuous process. To further enhance your game development prowess, don’t miss our Roblox Game Development Mini-Degree. Dive in, experiment, and keep advancing on your path to becoming a top-notch game developer with us at Zenva!

Did you come across any errors in this tutorial? Please let us know by completing this form and we’ll look into it!

Python Blog Image

FINAL DAYS: Unlock coding courses in Unity, Godot, Unreal, Python and more.