Unity Basic Course: What is C# Data Type?

Hello! In this post, we will take an in-depth look at one of the fundamental concepts of the programming language C# used in Unity: ‘Data Types’. Data types are a crucial factor in programming as they determine how data is stored and processed. Choosing the right data type can significantly enhance the efficiency, performance, and stability of your code.

1. Importance of Data Types

Data types define the kinds of values that can be stored in a variable. For example, different data types must be used when defining a variable to store numbers and one to store strings. C# provides various data types, each with different memory usage and types of data that can be stored.

2. Basic Data Types in C#

2.1 Integer Types

Integer types are data types that can represent whole numbers without decimals. C# offers several types of integers:

  • int: Can store values from -2,147,483,648 to 2,147,483,647. It is the most commonly used integer type.
  • short: Can store values from -32,768 to 32,767. It is used when you want to save memory.
  • long: Can store values from -9,223,372,036,854,775,808 to 9,223,372,036,854,775,807. It is used when dealing with very large integers.
  • byte: Can store values from 0 to 255 and uses 1 byte (8 bits) of memory. It is mainly used for processing binary data or small values.

Here’s how to declare integer variables:


int myInteger = 10;
short myShort = 30000;
long myLong = 9223372036854775807;
byte myByte = 255;

2.2 Floating Point Types

Floating point types can represent values that have decimal points. In C#, the following two are generally used:

  • float: A 32-bit floating-point type that can store values from approximately ±1.5 x 10-45 to ±3.4 x 1038. It uses less memory and provides approximately 7 digits of precision.
  • double: A 64-bit floating-point type that can handle a very large range of values and provides about 15 digits of precision. In most cases, it is recommended to use double for floating-point variables.

Here’s how to declare floating point variables:


float myFloat = 3.14f; // You need to append 'f' to specify it's a float
double myDouble = 3.14159265358979;

2.3 Character Type

The character type is used to store a single character. The character type used in C# is char, which stores one character using a 16-bit Unicode value.


char myChar = 'A';

2.4 String Type

The string type is a sequence of characters, and it can be declared using the string type provided by C#. A string is effectively an immutable object, meaning it cannot be modified and is used to create new strings.


string myString = "Hello, Unity!";

3. Type Casting

There are many instances where conversion between different data types is necessary. This process is called ‘Type Casting’. C# provides two methods for this: explicit conversion and implicit conversion.

3.1 Implicit Conversion

Implicit conversion is a conversion that occurs automatically without loss of information. For example, when converting an integer to a floating-point type, C# automatically converts the integer to a float.


int myInt = 123;
double myDouble = myInt; // Implicit conversion

3.2 Explicit Conversion

Explicit conversion may involve loss of information, so it is performed forcibly by the programmer. A cast operator is required for this.


double myDouble = 9.78;
int myInt = (int)myDouble; // Explicit conversion

4. Nullable Types in C#

In certain situations, a variable may not have a value (it may be null). To handle this, C# provides Nullable types. This is done by appending ‘?’ to a value type when declaring it.


int? myNullableInt = null; // Nullable int

5. Arrays and Lists

In C#, arrays or lists are used to handle collections of data types. Arrays are used to manage fixed-size collections of the same data type, while lists are dynamically resizable collections.

5.1 Arrays


int[] myArray = new int[5]; // Declare an integer array
myArray[0] = 1;
myArray[1] = 2;

5.2 Lists


List myList = new List(); // Declare a list
myList.Add(1); // Add an element to the list
myList.Add(2);

6. Custom Types

In C#, you can create custom data types using classes. This allows for the expression of more complex and structured data.


public class Player
{
    public string Name;
    public int Health;
    
    public Player(string name, int health)
    {
        Name = name;
        Health = health;
    }
}

7. Conclusion

In this post, we learned about the basic data types in C#. We covered various topics including types and usage of basic data types, type casting, and custom data types. I hope this helps you in your Unity development.

The choice and use of data types significantly affect the performance and readability of the code you write, so please understand and utilize them well. In the next tutorial, we will discuss the concept of Object-Oriented Programming (OOP). Thank you!