Execute a function when it is retrieved via a String

Question

I have the situation that I retrieve a function in a string:

var function_name = "function Test(value){return value + 1}";

now I want to execute the function and store the value inside a variable so for example:

var value = 10;
var calc_value = function Test(value){return value + 1}
console.log(calc_value); // should show 11

But I do not know how I could get the function out of the string and execute it and store the result in a variable.

Any ideas how I could do that? I know that having the function inside a string is not ideal at all but I can not change that.

Please have a look at eval(): https://developer.mozilla.org/en/docs/Web/JavaScript/Reference/Global_Objects/eval — Rob, Sep 22 '17 at 08:20
First of all, you can't declare function as variable. `function`is reserved word. — RamaKrishna, Sep 22 '17 at 08:21

score 3 · Accepted Answer · answered Sep 22 '17 at 08:20

3

You can use eval(). For eg:

var str='function Test(value){return value + 1}';
    eval(str);
    alert(Test(3));

answered Sep 22 '17 at 08:20

Tejasvi Karne

score 0 · Answer 2 · answered Sep 22 '17 at 08:21

0

You can use eval() to evaluate the expression

var str="function Test(value){return value + 1}";
eval(str);
console.log(Test(1));

answered Sep 22 '17 at 08:21

marvel308

2 Answers2