In C programming, type conversion (also known as type casting) is the process of converting a value of one data type to another. This can be necessary in situations where a function expects a certain type of data, or when performing arithmetic or comparison operations involving different data types.
There are two main types of type conversion in C:
- Implicit type conversion
- Explicit type conversion
1. Implicit type conversion (also known as “type promotion”) – this occurs automatically when the compiler needs to perform an operation on two values of different data types. The compiler will convert one or both of the values to a “higher” data type in order to perform the operation.
For example, if you try to add an integer and a floating-point value, the compiler will automatically convert the integer to a floating-point value before performing the addition:
int x = 10; float y = 3.14; float sum = x + y; // x is implicitly converted to a float before the addition is performed
2. Explicit type conversion (also known as “type casting”) – this involves manually converting a value from one data type to another using a type cast operator. The type cast operator is a unary operator that takes the form of a set of parentheses containing the target data type, followed by the value to be converted.
For example, to explicitly convert a floating-point value to an integer, you can use the following code:
float x = 3.14; int y = (int)x; // x is explicitly cast to an int
Note that when performing explicit type conversion, the value being converted may lose precision or information.
For example, if you convert a floating-point value to an integer, any fractional part of the value will be truncated.