How to run a dynamically generated function stored in a variable in Javascript

Question

I have a function that gets called from dynamically generated html, but its not being executed

The function.

$.check = function(s){
alert (s);
}

....and then... the value of the contents of the following function object is the above function's call.

value is  var s = 'hey';$.check(s);

function( event, ui) {
//////The following does nothing, not even an error
      return ui.item.value;
       }

How do I execute the function stored in "value";

i am not sure if i got what you are asking but if you want to call the function in value then call like ui.item.value(); — Cerlin
– Cerlin, Commented Nov 26, 2014 at 10:41
Nah, this whole thing: ui.item.value, has "var s = 'hey';$.check(s);" stored in it. So i want to run that. — Relm
– Relm, Commented Nov 26, 2014 at 10:44
Ah, @CerlinBoss you typed your comment as I typed my answer! Sorry, dude. — deitch
– deitch, Commented Nov 26, 2014 at 10:50

deitch · Accepted Answer · 2014-11-26 10:49:47Z

1

The only way to do this in a browser is eval

eval(ui.item.value);

Node supports more advanced things like vm.runInNewContext(value,{/* context */}).

answered Nov 26, 2014 at 10:49

deitch

14.8k15 gold badges75 silver badges102 bronze badges

Sign up to request clarification or add additional context in comments.

2 Comments

Yeah, lots of arguments about it. I am mixed myself, which is why I say "dangerous". I prefer to avoid it whenever I can, but cannot always.

Michel Tomé · Accepted Answer · 2014-11-26 10:45:12Z

0

It's simple, just do:

function( event, ui) {
    if (typeof ui.item.value === 'function') {
        ui.item.value.call();
    }
}

Create that var s as a function, like so:

ui.item.value = function () {
    var s = 'hey';
    $.check(s);
}

answered Nov 26, 2014 at 10:45

Michel Tomé

3892 silver badges12 bronze badges

I don't think this will seen as a function where u are checking if its a function, there's variable before the function itself.

But when you build that var s and the $.check, just wrap it in a function in your value