内部匿名函数如何具有外部函数的范围？

Question

In the script shown below

$(function(){
    var outerValue="OuterValue";
    $('#btnScope').click(function(){
        alert(outerValue);
    });
});

The outer function (ie $() ) executes when the page loads. At this time click event will be bound to anonymous function (which alerts). This function uses value of outerValue which might have lost scope after completing the ready( $() ) function. How this is possible? How could I know the scope of variable?

How the interpreter define its scope?

Answer 1

The outer scope is not lost . The scoping as you describe it is fairly accurate.

A variable's scope is roughly where it's defined (where var is). Any inner scope can access anything in it's outer scope. Only functions have scope though; not if , for , while or switch .