C# data types

Value types

• Value type variables can be assigned directly to a value. They are derived from the class System.valueType.
• Value types directly contain data. Such as int, char, and float, which store numbers, characters, and floating-point numbers respectively. When you declare an int, the system allocates memory to store the value.

Value types can be roughly divided into the following categories:

Reference types

• Reference types do not contain the actual data stored in variables, but they do contain references to variables.
• In other words, they refer to a memory location. When multiple variables are used, the reference type can point to a memory location. If the memory location data is changed by one variable, the other variables automatically reflect the change in value. The built-in reference types are: Object, Dynamic, and String.

– Object Indicates the Object type

The Object Type is the ultimate base class for all data types in C#’s Common Type system-cts. Object is an alias of the System.Object class. So an Object type can be assigned a value of any other type (value type, reference type, predefined type, or user-defined type). However, before assigning a value, a type conversion is required.

When a value type is converted to an object type, it is called boxing *; On the other hand, when an object type is converted to a value type, it is called unboxing.

object obj;
obj = 100; // This is the case
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– Dynamic indicates the Dynamic type

You can store any type of value in a dynamic data type variable. Type checking for these variables occurs at run time.

dynamic <variable_name> = value;
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Such as:

dynamic d = 20;
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Dynamic types are similar to object types, but type checking for object type variables occurs at compile time, whereas type checking for dynamic type variables occurs at run time.

– The value is a String

The String type allows you to assign any String value to a variable. The String type is an alias of the System.String class. It is derived from the Object type. String values can be assigned in two forms: quotes and @ quotes. Such as:

String str = "runoob.com";
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An @ quoted string:

@"runoob.com";
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A string can be preceded by an @ (called a “verbatim string”) to treat an escaped character (\) as a normal character, such as:

string str = @"C:\Windows";
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Is equivalent to:

string str = "C:\\Windows";
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Any newline in the @ string is allowed, and newlines and indent Spaces count to the length of the string.

string str = @"<script type=""text/javascript""> <! -- --> </script>";
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User-defined reference types can be class, Interface, or Delegate.

Pointer types

A pointer type variable stores the memory address of another type. Pointers in C# have the same functionality as Pointers in C or C++. Syntax for declaring pointer types:

type* identifier;
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Such as:

char* cptr;
int* iptr;
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