如何使我的功能在全局范围内可见

Question

I have following javascript to make function $E

On window.onload it throws error that $E is not defined.

So my question is how do I make $E visible in the global scope so I can access it outside the (function(){})(); function

window.onload = function() {
   $E("bhavik").warn();
}
(function() {
                function $E(s) {
                    return new ge(s)
                }
                function ge(sel) {
                    this.arg = sel;
                    return this;
                }
                ge.proto = ge.prototype = {warn: function() {
                        alert(this.arg)
                    }};
                ge.proto.hi=function(){alert("hi "+this.arg)}
                $E("bhavik").hi();
            })(window);

Answer 1

To make a variable visible in the global scope, set it on the window object. For example:

function $E(s) {
   return new ge(s);
}
window.$E = $E;

Answer 2

Javascript : How to create global functions & variables

http://www.w3schools.com/jsref/jsref_obj_global.asp

You should set a window variable to your function to make it accessible. These links will help. Also you can define function outside and make it global.

For detailed study,

https://developer.mozilla.org/en-US/docs/JavaScript/Reference/Functions_and_function_scope

javascript function scope

Answer 3

This made the function global from within another function when tested:

function test()
{
  window.$E = function() { alert('test'); };
}

test();
$E();

http://jsfiddle.net/WEg4b/

So, to adapt it to your needs:

(function() {

                function ge(sel) {
                    this.arg = sel;
                    return this;
                }

                window.$E = function $E(s) { return new ge(s); };

                ge.proto = ge.prototype = {warn: function() {
                        alert(this.arg)
                    }};
                ge.proto.hi=function(){alert("hi "+this.arg)}
                $E("bhavik").hi();
            })(window);

Answer 4

Just declare it outside the anonymous function. By declaring all that code inside the module you are creating a new scope, isolated from all other code so, if you want that to be available in the global context, just declare it outside of that function.

Answer 5

try to change the order of function declaration

(function() {
            function $E(s) {
                return new ge(s)
            }
            window.$E = $E;
            function ge(sel) {
                this.arg = sel;
                return this;
            }
            ge.proto = ge.prototype = {warn: function() {
                alert(this.arg)
            }};
            ge.proto.hi=function(){alert("hi "+this.arg)}
            $E("bhavik").hi();
        })(window);
window.onload = function() {
    $E("bhavik").warn();