JavaScript eval() function

eval()The function calculates or executes JavaScript code represented as a string.

If the string represents an expression, eval() will evaluate the expression.

If the parameter represents one or more JavaScript statements, the eval() function will execute these statements.

If the parameter of eval() is not a string, the parameter returned by eval() remains unchanged.

Syntax:

eval(string)

Example

var x =　20;
var y =　10;
var a = eval('x　*　y');
var b = eval('2　+　2');
var c = eval('x　+　15');
var res = a　+　'<br>'　+　b　　+　'<br>'　+　c;

All browsers fully support the eval() function:

Function
eval()	Is	Is	Is	Is	Is

Parameter	Description
string	A string representing a JavaScript expression, statement, or sequence of statements.

Return Value:	The completion value of the given code. If the completion value is empty, it returns undefined.
JavaScript Version:	ECMAScript 1