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PHP Parameterized functions are the functions with parameters. You can pass any number of parameters inside a function. These passed parameters act as variables inside your function.

They are specified inside the parentheses, after the function name.

The output depends upon the dynamic values passed as the parameters into the function.

PHP Parameterized Example 1

Addition and Subtraction

In this example, we have passed two parameters $x and $y inside two functions add() and sub().

<!DOCTYPE html>  
<html>  
<head>  
    <title>Parameter Addition and Subtraction Example</title>  
</head>  
<body>  
<?php  
        //Adding two numbers  
         function add($x, $y) {  
            $sum = $x + $y;  
            echo "Sum of two numbers is = $sum <br><br>";  
         }   
         add(467, 943);  
  
         //Subtracting two numbers  
         function sub($x, $y) {  
            $diff = $x - $y;  
            echo "Difference between two numbers is = $diff";  
         }   
         sub(943, 467);  
      ?>  
</body>  
</html>

Output:

PHP Parameterized Example 2

Addition and Subtraction with Dynamic number

In this example, we have passed two parameters $x and $y inside two functions add() and sub().

<?php  
//add() function with two parameter  
function add($x,$y)    
{  
$sum=$x+$y;  
echo "Sum = $sum <br><br>";  
}  
//sub() function with two parameter  
function sub($x,$y)    
{  
$sub=$x-$y;  
echo "Diff = $sub <br><br>";  
}  
//call function, get  two argument through input box and click on add or sub button  
if(isset($_POST['add']))  
{  
//call add() function  
 add($_POST['first'],$_POST['second']);  
}     
if(isset($_POST['sub']))  
{  
//call add() function  
sub($_POST['first'],$_POST['second']);  
}  
?>  
<form method="post">  
Enter first number: <input type="number" name="first"/><br><br>  
Enter second number: <input type="number" name="second"/><br><br>  
<input type="submit" name="add" value="ADDITION"/>  
<input type="submit" name="sub" value="SUBTRACTION"/>  
</form>

Output:

We passed the following number,

Now clicking on ADDITION button, we get the following output.

Now clicking on SUBTRACTION button, we get the following output.

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c, programming languages

C Types of user-defined functions

In this tutorial, you will learn about different approaches you can take to solve the same problem using functions.

These 4 programs below check whether the integer entered by the user is a prime number or not.

The output of all these programs below is the same, and we have created a user-defined function in each example. However, the approach we have taken in each example is different.

Example 1: No arguments passed and no return value

#include <stdio.h>

void checkPrimeNumber();

int main()
{
    checkPrimeNumber();    // argument is not passed
    return 0;
}

// return type is void meaning doesn't return any value
void checkPrimeNumber()
{
    int n, i, flag = 0;

    printf("Enter a positive integer: ");
    scanf("%d",&n);

    for(i=2; i <= n/2; ++i)
    {
        if(n%i == 0)
        {
            flag = 1;
        }
    }
    if (flag == 1)
        printf("%d is not a prime number.", n);
    else
        printf("%d is a prime number.", n);
}

The checkPrimeNumber() function takes input from the user, checks whether it is a prime number or not and displays it on the screen.

The empty parentheses in checkPrimeNumber(); statement inside the main() function indicates that no argument is passed to the function.

The return type of the function is void. Hence, no value is returned from the function.

Example 2: No arguments passed but a return value

#include <stdio.h>
int getInteger();

int main()
{
    int n, i, flag = 0;

   // no argument is passed
    n = getInteger();    

    for(i=2; i<=n/2; ++i)
    {
        if(n%i==0){
            flag = 1;
            break;
        }
    }

    if (flag == 1)
        printf("%d is not a prime number.", n);
    else
        printf("%d is a prime number.", n);

    return 0;
}

// returns integer entered by the user
int getInteger()       
{
    int n;

    printf("Enter a positive integer: ");
    scanf("%d",&n);

    return n;
}

The empty parentheses in the n = getInteger(); statement indicates that no argument is passed to the function. And, the value returned from the function is assigned to n.null

Here, the getInteger() function takes input from the user and returns it. The code to check whether a number is prime or not is inside the main() function.

Example 3: Argument passed but no return value

#include <stdio.h>
void checkPrimeAndDisplay(int n);

int main()
{
    int n;

    printf("Enter a positive integer: ");
    scanf("%d",&n);

    // n is passed to the function
    checkPrimeAndDisplay(n);

    return 0;
}

// return type is void meaning doesn't return any value
void checkPrimeAndDisplay(int n) 
{
    int i, flag = 0;

    for(i=2; i <= n/2; ++i)
    {
        if(n%i == 0){
            flag = 1;
            break;
        }
    }
    if(flag == 1)
        printf("%d is not a prime number.",n);
    else
        printf("%d is a prime number.", n);
}

The integer value entered by the user is passed to the checkPrimeAndDisplay() function.

Here, the checkPrimeAndDisplay() function checks whether the argument passed is a prime number or not and displays the appropriate message.

Example 4: Argument passed and a return value

#include <stdio.h>
int checkPrimeNumber(int n);

int main()
{
    int n, flag;

    printf("Enter a positive integer: ");
    scanf("%d",&n);

    // n is passed to the checkPrimeNumber() function
    // the returned value is assigned to the flag variable
    flag = checkPrimeNumber(n);

    if(flag == 1)
        printf("%d is not a prime number",n);
    else
        printf("%d is a prime number",n);

    return 0;
}

// int is returned from the function
int checkPrimeNumber(int n)
{
    int i;

    for(i=2; i <= n/2; ++i)
    {
        if(n%i == 0)
            return 1;
    }

    return 0;
}

The input from the user is passed to the checkPrimeNumber() function.

The checkPrimeNumber() function checks whether the passed argument is prime or not.

If the passed argument is a prime number, the function returns 0. If the passed argument is a non-prime number, the function returns 1. The return value is assigned to the flag variable.

Depending on whether flag is 0 or 1, an appropriate message is printed from the main() function.

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c, programming languages

C user-defined functions

In this tutorial, you will learn to create user-defined functions in C programming with the help of an example.

A function is a block of code that performs a specific task.

C allows you to define functions according to your need. These functions are known as user-defined functions. For example:

Suppose, you need to create a circle and color it depending upon the radius and color. You can create two functions to solve this problem:

createCircle() function
color() function

Example: User-defined function

Here is an example to add two integers. To perform this task, we have created an user-defined addNumbers().

#include <stdio.h>

int addNumbers(int a, int b); // function prototype

int main()

{

int n1,n2,sum;

printf("Enters two numbers: ");

scanf("%d %d",&n1,&n2);

sum = addNumbers(n1, n2); // function call

printf("sum = %d",sum);

return 0;

}

int addNumbers(int a, int b) // function definition

{

int result; result = a+b; return result; // return statement

}

Function prototype

A function prototype is simply the declaration of a function that specifies function’s name, parameters and return type. It doesn’t contain function body.

A function prototype gives information to the compiler that the function may later be used in the program.

Syntax of function prototype

returnType functionName(type1 argument1, type2 argument2, ...);

In the above example, int addNumbers(int a, int b); is the function prototype which provides the following information to the compiler:

name of the function is addNumbers()
return type of the function is int
two arguments of type int are passed to the function

The function prototype is not needed if the user-defined function is defined before the main() function.

Calling a function

Control of the program is transferred to the user-defined function by calling it.

Syntax of function call

functionName(argument1, argument2, ...);

In the above example, the function call is made using addNumbers(n1, n2); statement inside the main() function.

Function definition

Function definition contains the block of code to perform a specific task. In our example, adding two numbers and returning it.

Syntax of function definition

returnType functionName(type1 argument1, type2 argument2, ...)
{
    //body of the function
}

When a function is called, the control of the program is transferred to the function definition. And, the compiler starts executing the codes inside the body of a function.

Passing arguments to a function

In programming, argument refers to the variable passed to the function. In the above example, two variables n1 and n2 are passed during the function call.

The parameters a and b accepts the passed arguments in the function definition. These arguments are called formal parameters of the function.

The type of arguments passed to a function and the formal parameters must match, otherwise, the compiler will throw an error.

If n1 is of char type, a also should be of char type. If n2 is of float type, variable b also should be of float type.

A function can also be called without passing an argument.

Return Statement

The return statement terminates the execution of a function and returns a value to the calling function. The program control is transferred to the calling function after the return statement.

In the above example, the value of the result variable is returned to the main function. The sum variable in the main() function is assigned this value.

Syntax of return statement

return (expression);

For example,

return a;
return (a+b);

C The type of value returned from the function and the return type specified in the function prototype and function definition must match.

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Tag: user define functions

PHP Parameterized Function

PHP Tutorial

Control Statement

PHP Functions

PHP Arrays

PHP Strings

PHP Math

PHP Form

PHP Include

State Management

PHP File

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PHP OOPs Concepts

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PHP Parameterized Example 1

PHP Parameterized Example 2

C Types of user-defined functions

Example 1: No arguments passed and no return value

Example 2: No arguments passed but a return value

Example 3: Argument passed but no return value

Example 4: Argument passed and a return value

C user-defined functions

C-Tutorial

C user-defined functions

Example: User-defined function

Function prototype

Syntax of function prototype

Calling a function

Syntax of function call

Function definition

Syntax of function definition

Passing arguments to a function

Return Statement

Syntax of return statement