keeping variable alive in a javascript function

Question

I want to house a variable in a function This variable will change state depending on user interaction

function plan_state(current){
    if (current != \'\')         


        

Answer 1

I believe the scope of your variable is too "low"; by defining the variable within the function, either as a parameter or explicitly as a var, it is only accessible within the function. In order to achieve what you're after, you can either implement the variable outside the scope of the function, at a more global evel (not recommened really).

However, after re-reading your question, it's slightly miss-leading. Would you not want to return state regardless of the current? I think you might be after something like so:

var state;
function plan_state(current)
{
    if (current != '' && current != state)
    {
        state = current;
    }
    return state;
} 

Alternative object structure:

function StateManager(state)
{
    this.state = state;

    this.getState = function(current)
    {
        if (current != '' && current != this.state)
        {
            this.state = current;
        }
        return this.state;
    }
}

// usage
var myStateManager = new StateManager("initial state here");
var theState = myStateManager.getState("some other state");