The jQuery event in the processor shall not be altered

[Bogopo]

Hello!

Please tell me why the variables created in the processor do not extend beyond its limits.

For example, there's nothing going to happen:

 $('#search').on('keyup', function(){
 a = 'test';

});
alert(a); //ничего не выведет

And comes out here:

 $('#search').on('keyup', function(){

 a = 'test';
 alert(a); //окно test

});

[simrah]

The buttons only work when compressed. function Processor, the code that is written after - worked after Establishment Processor.

a doesn't exist until the button is pressed. First off alertand then press any button in. #search and alert with conclusion a It's a flash.

$('#search').on('keyup', function() {
    a = 'test';
    console.log(a); // test
});
console.log(a); // a is not defined

$('#search').on('keyup', function() {

a = this.value;

f(a);

});

function f(a) {

console.log(a);

}

<script src="https://ajax.googleapis.com/ajax/libs/jquery/2.1.1/jquery.min.js">

</script>

<input id='search'>

---

You can declare a variable before the processor, assign a value to it in the processor and then use it anywhere.

a = null;

$('#search').on('keyup', function() {

a = this.value;

});
$('button').click(function() {

console.log(a);

});

<script src="https://ajax.googleapis.com/ajax/libs/jquery/2.1.1/jquery.min.js">

</script>

<input id='search'>

<button>получить значение</button>