Cpp - Function Function Creation
Introduction
General form of a function
[type] name([declaration_list]) // Function header { . . What will be done // Function block . . }// End
| Item | Meaning |
|---|---|
| type | the function type, that is, the type of the return value. |
| name | the function name, like a variable name and should indicate the purpose of the function. |
| declaration_list | contains the names of the parameters and types. The list can be empty. void is equivalent to an empty list. |
The parameters declared in a list are local variables.
They are created when the function is called and initialized by the values of the arguments.
When test( 10, -7.5); is called, the parameter arg1 is initialized with a value of 10 and arg2 with -7.5.
Prototype
The prototype is the declaration of the function and describes only the formal interface of that function.
You can omit parameter names from the prototype.
Demo
#include <iostream> using namespace std; void test( int, double ); // Prototype int main() /* w w w . ja v a 2s . co m*/ { cout << "\nNow function test() will be called.\n"; test( 10, -7.5); // Call cout << "\nAnd back again in main()." << endl; return 0; } void test(int arg1, double arg2 ) // Definition { cout << "\nIn function test()." << "\n 1. argument: " << arg1 << "\n 2. argument: " << arg2 << endl; }
Result
