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TypeCasting in C

Typecasting​

  • Typecasting is a way to make a variable of one type, such as an int, act like another type, such as a char, for one single operation.

Why TypeCasting​

  • Type casting can be useful in various scenarios, such as converting between different numeric types, performing arithmetic operations on mixed data types, or working with pointers of different types.

  • Casting is necessary when you want to perform operations that involve different data types, or when you want to store a value of one type into a variable of another type.

  • By casting the value, you inform the compiler how you want the value to be treated.

The syntax for typecasting is:

int x;
float y;
y = (float) x;

Types of type casting in C:​

There are two types of type casting in C:

Implicit Type Casting (Coercion):​

  • This type of casting is performed automatically by the compiler.

  • The compiler automatically converts one type of data to another type without requiring explicit instructions from the programmer.

  • This conversion is also known as Coercion, and performed when the compiler determines that it is safe to do so and the conversion does not result in a loss of data or precision.

  • For example: Assigning an integer to a floating-point number does not require explicit casting because the compiler can perform it implicitly.

Example​

#include <stdio.h>

int main() {
    
  // character variable
  char alphabet = 'a';
  printf("Character Value: %c\n", alphabet);

  // assign character value to integer variable
  int number = alphabet;
  printf("Integer Value: %d", number);
     
  return 0;
}

Output:

Character Value: a
Integer Value: 97

Explicit Type Casting:​

  • This type of casting is done explicitly by the programmer using the casting operator (type).

  • It is necessary when you want to convert a value to a type that is not automatically convertible.

  • Explicit casting can be used to convert between different numeric types, pointers, or even between different types of pointers.

Example​

#include<stdio.h>
int main() {

  // create an integer variable
  int number = 35;
  printf("Integer Value: %d\n", number);
  
  // explicit type conversion
  double value = (double) number;
  printf("Double Value: %.2lf", value);
    
  return 0;
}

Output:

Integer Value: 35
Double Value: 35.00

TypeCasting Advantages​

  • Data Conversion: It allows you to convert data from one type to another, facilitating operations and assignments involving different data types.

  • Precision and Control: Type casting provides control over how values are interpreted and processed, allowing you to specify precision and representation.

  • Compatibility: It helps establish compatibility between different parts of a program with different data types, enabling integration with libraries or modules.

  • Pointer Manipulation: Casting pointers allows for dynamic memory allocation, pointer arithmetic, and interoperability between data structures.

  • Expression Evaluation: Type casting aids in evaluating complex expressions by defining intermediate or final result types.

note

Remember to use type casting judiciously, understanding the implications and potential risks involved.