Question

I have a requirement where I get the anchor tags id and based on the id I determine which function to execute.. so is there anything that suites below code

function treeItemClickHandler(id)
{
 a=findDisplay(id);
 a();
}

Answer 1

Sure, functions are first class objects in JavaScript. For example, you can create a map (an object) which holds references to the functions you want to call:

var funcs = {
   'id1': function(){...},
   'id2': function(){...},
   ...
};

function treeItemClickHandler(id) {
    if(id in funcs) {
        funcs[id]();
    }
}

As functions are treated as any other value, you can also return them from another function:

function findDisplay(id) {
    // whatever logic here
    var func = function() {};

    return func;
}