variable scope issue with javascript

Question

In my application, originally those codes works:

var htm = "<div> My content </div>";   
$("#divprint").html(htm);
window.setTimeout('window.print()', 4000);

however, when I try to wrap it within an if statement, it won't print:

var canprint= $.cookie("actionprint");  
alert("I am outside " + canprint);
if(canprint == null){
    alert("I am inside");
    var htm = "<div> My content </div>";
    window.setTimeout('window.print()', 4000);
}

when I run this codes, I only got first alert: "I am outside null"

As javascript's scope is function level, I am wondering, why that if failed?

I don't see any function definition in your code. Btw, console.log(typeof canprint, canprint); — zerkms
– zerkms, Commented Jan 23, 2014 at 4:29
did you forget a double quotation mark on the declaration of variable htm? — gigadot
– gigadot, Commented Jan 23, 2014 at 4:31
$.cookie() for the props that don't exist returns undefined. — Ram
– Ram, Commented Jan 23, 2014 at 4:32

vasudevanp · Accepted Answer · 2014-01-23 04:46:27Z

1

Can you try the if statement like,

if (!canprint)

answered Jan 23, 2014 at 4:46

vasudevanp

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Comments

JavaScripter · Accepted Answer · 2014-01-23 05:34:14Z

1

OK. As weird it is:

Firstly, I tried to print out:

  console.log(typeof canprint, canprint);

amazingly, result is:

string null

so, I changed to if condition to:

if(canprint == "null")

then it can goes inside that if.

Though this is working, does anyone who can explain what has happened? This is really out of my expedition.

edited Jan 23, 2014 at 5:34

answered Jan 23, 2014 at 5:24

JavaScripter

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Comments

Community · Accepted Answer · 2017-05-23 12:23:37Z

0

Remove the quote and parenthesis from setTimeout function

window.setTimeout(window.print, 4000);

And use something like this: jQuery check if Cookie exists, if not create it

var CookieSet = $.cookie('cookietitle', 'yourvalue');

     if (CookieSet == null) {
          // Do Nothing
     }
     if (jQuery.cookie('cookietitle')) {
          // Reactions
     }

edited May 23, 2017 at 12:23

CommunityBot

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answered Jan 23, 2014 at 4:31

Bhojendra Rauniyar

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2 Comments

Barmar Over a year ago

Although this is a reasonable suggestion, it isn't necessary; the original call will also work. It doesn't answer the question.

Barmar Over a year ago

This doesn't seem right. It sets the cookie before checking if it's already set.

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