JavaScript_Succinctly

window). The second way is to use the this keyword in the global scope. Each of these
is detailed in the following sample.
Sample: sample67.html
var foo = 'bar';
windowRef1 = window;
windowRef2 = this;
console.log(windowRef1, windowRef2); // Logs reference to window object.
console.log(windowRef1.foo, windowRef2.foo); // Logs 'bar', 'bar'.
In this example, we explicitly store a reference to the head object in two variables that
are then used to gain access to the global foo variable.
The head object is implied and typically not referenced explicitly
Typically a reference to the head object is not used because it is implied. For example,
in the browser environment window.alert and alert() are essentially the same
statement. JavaScript fills in the blanks here. Because the window object (i.e. the head
object) is the last object checked in the scope chain for a value, the window object is
essentially always implied. In the next example, we leverage the alert() function
which is contained in the global scope.
Sample: sample68.html
var foo = { // window is implied here, window.foo
fooMethod: function () {
alert('foo' + 'bar'); // window is implied here, window.alert
window.alert('foo' + 'bar'); // window is explicitly used, with
the same effect.
}
}
foo.fooMethod(); // window is implied here, window.foo.fooMethod()
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