Passing values to JavaScript Function
In this JavaScript Tutorial you will learn about how to pass values to and also how to return values from a JavaScript function.
Passing Values to function:
Values can be passed to a function as parameters.
The general syntax for passing values to a function in JavaScript is:
………………………………………… }
function name_of_function(argument1,argument2,…argumentn)
{
//Block of Code
…………………………………………
In the above argument1, argument2,…argumentn represents the values passed to the function.
For Example:
Suppose a programmer wants to create a function with name exforsys, which takes two values x and y.
These two values are passed from the calling program. Then function takes up the shape as follows:
………………………………………… }
function exforsys(x,y)
{
//Block of Code
…………………………………………
Suppose the values passed to the function from the calling program are 10 and 15.
Then, from the calling program the function is called as follows:
|
Returning Values from Function:
After executing the function, there may be situations where the programmer wants to return some value from the function to the calling program. This is achieved by using the return statement in JavaScript.
The general syntax of this return statement is as follows:
return variablename
An example to understand this concept:
Suppose the programmer wants to create a function with name exforsys, which takes two values x and y. The function is written to add these values and return the result of the addition to the calling program. This is achieved in JavaScript as follows:
function exforsys(x,y)
{
z=x+y
return z
}
Thus, in the above example, the added value x+y is stored in variable z and returned to the calling program using the statement
return z
In the calling program, suppose the values passed to the function from the calling program are 10 and 15. From the calling program, the function is called as follows:
result=exforsys(10,15)
The returned value z is the addition of two values x and y of the function exforsys . This is stored in the variable result in the calling program.
A complete example of a function in JavaScript:
<body>
<html>
<head>
<script type="text/javascript">
function exforsys(x,y)
{
return x+y
}
script>
head>
<script type="text/javascript">
document.write(exforsys(10,15))
script>
body>
html>
The output of the above program is
25
Thus, in the above example, the function creation is done on the <head> section of the program. The function exforsys is called with values 10 and 15 passed to the function and the added value 25 is returned from the function using the return statement. This is stored in the function name exforsys and then printed in the calling program.