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Question

I have function that reads json document, dayNames and monthNames are visible outside function, but date format isn't. Inside function it correctly prints its value but outside it doesn't update outside value. So why dateFormat doesn't update outside function?

var dayNames = [];
var monthNames = [];
var dateFormat = "";
$.getJSON("/Scripts/cldr/main/"+ culture + "/ca-gregorian.json", function (json) {
    $.each(json.main.@(System.Threading.Thread.CurrentThread.CurrentCulture.Name).dates.calendars.gregorian.days.format.short, function (key, val) {
        dayNames.push(val);
    });
    $.each(json.main.@(System.Threading.Thread.CurrentThread.CurrentCulture.Name).dates.calendars.gregorian.months["stand-alone"].wide, function (key, val) {
        monthNames.push(val);
    });
    dateFormat = json.main.@(System.Threading.Thread.CurrentThread.CurrentCulture.Name).dates.calendars.gregorian.dateFormats.medium;
    console.log(dateFormat);  //Output: y-MM-dd
});
console.log(dateFormat); //Output: 

Answer 1

The problem is $.getJSON() is an asynchronous call. The console.log(dateFomrat) outside the function runs before the function finishes. The code continues while the $.getJSON() is running so dateFormat isn't set when the second(outside) console.log() executes.