C# Data Type

The variables in C#, are categorized into the following types:

• Value types
• Reference types
• Pointer types

Value types

Value type variables can be assigned a value directly. They are derived from the class System.ValueType.

The value types directly contain data. Some examples are int, char, and float, which stores numbers, alphabets, and floating point numbers, respectively. When you declare an int type, the system allocates memory to store the value.

To get the exact size of a type or a variable on a particular platform, you can use the sizeof method

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;

namespace ConsoleApp
{
    class Program
    {
        static void Main(string[] args)
        {
            Console.WriteLine("Size of int: {0}", sizeof(int));
            Console.ReadLine();
        }
    }
}
// Size of int: 4

Reference types

The reference types do not contain the actual data stored in a variable, but they contain a reference to the variables.

In other words, they refer to a memory location. Using multiple variables, the reference types can refer to a memory location. If the data in the memory location is changed by one of the variables, the other variable automatically reflects this change in value. Example of built-in reference types are: object, dynamic, and string

Object Type

The Object Type is the ultimate base class for all data types in C# Common Type System (CTS). Object is an alias for System.Object class. The object types can be assigned values of any other types, value types, reference types, predefined or user-defined types. However, before assigning values, it needs type conversion.

Dynamic Type

You can store any type of value in the dynamic data type variable. Type checking for these types of variables takes place at run-time

Dynamic types are similar to object types except that type checking for object type variables takes place at compile time

String Type

The String Type allows you to assign any string values to a variable. The string type is an alias for the System.String class. It is derived from object type. The value for a string type can be assigned using string literals in two forms: quoted and @quoted.

Pointer types

Pointer type variables store the memory address of another type. Pointers in C# have the same capabilities as the pointers in C or C++

using System;

namespace ConsoleApp
{
    class Program
    {
        static void Main(string[] args)
        {
            object obj;
            obj = 100;

            dynamic d = 20;

            String str = "Tutorials Point";
            // @"Tutorials Point";

            char* cptr;
            int* iptr;
        }
    }
}