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Creates a new function.


function functionName ( [ argname1  [, ...[, argnameN ] ] ] )

functionName = new Function( [ argname1 ,  [... argnameN ,] ] body );
Required. The name of the newly created function
Optional. A list of arguments the function accepts.
Optional. Parameters are the named arguments in the function declaration’s arguments list. Parameters must be valid identifiers. If there is more than one, parameters are separated by commas.
Optional. A string that contains the block of JavaScript code to be executed when the function is called.


To declare a function that adds the two arguments passed to it, you can do it in one of two ways:

//Method 1
 function add(x, y)
    return(x + y);

//Method 2
 var add = function(x, y) {

//In either case, you call the function with a line of code similar to this:
 add(2, 3);


The function is a basic data type in JavaScript. Syntax 1 creates a function value that JavaScript converts into a Function object when necessary. JavaScript converts Function objects created by Syntax 2 into function values at the time the function is called.

Syntax 1 is the standard way to create new functions in JavaScript. Syntax 2 is an alternative form used to create function objects explicitly.

Note – When you call a function, make sure that you always include the parentheses and any required arguments. Calling a function without parentheses causes the function itself to be returned, instead of the return value of the function.


prototype Property


valueOf Method

See also

Other articles


  • Microsoft Developer Network: Article