I am trying to get a file content using jQuery .get() method like below
var news;
$.get('news.txt', function (dat) {
news = dat;
if ($('#removeN').is(':checked')) {
news = "";
}
alert(news) // Displaying exact result;
});
alert(news) // Displaying undefined..; Why?
Someone please clarify my doubt.
AJAX is asynchronous.
Your last line runs before you get a response from the server.
var news;
$.get('news.txt', function (dat) {
news = dat;
if ($('#removeN').is(':checked')) {
news = "";
}
alert(news) // BEFORE THIS!
});
alert(news) // THIS EXECUTES
use this instead if you want to do something with the news:
$.get('news.txt', function (dat) {
news = dat;
if ($('#removeN').is(':checked')) {
news = "";
}
doSomething(news) // Displaying exact result;
});
var doSomething = function(data) {
alert(data);
}
You should also be able to separate out concerns..
var news;
$.get('news.txt', function (dat) {
//process news
}).done(function(dat){
//display news, or maybe more processing related to this particular function block
alert(news);
}).fail(function(){
//oops, something happened in attempting to get the news.
alert("failed to get the news");
}).always(function(){
//this eventually gets called regardless of outcome
});
etc.
The second parameter to $.get is a callback. Essentially what $.get is doing is setting up an event handler to the content loaded event, and saying "here's the function I want to run when this event is fired." Like others have said, it hasn't fired that event yet, so the code rambles through and finds your uninitialized variable.
