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Is there a “null coalescing” operator in JavaScript?

...he assignment will use the second operand. Beware of all the cases below: alert(Boolean(null)); // false alert(Boolean(undefined)); // false alert(Boolean(0)); // false alert(Boolean("")); // false alert(Boolean("false")); // true -- gotcha! :) This means: var whatIWant = null || new ShinyObject...
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What is the instanceof operator in JavaScript?

... @Siku-Siku.Com - I don't see any trick to it var zero = 0; alert(zero); zero = "0"; alert(zero) we went from a primitive int to a primitive string without any issues. – JonH Oct 18 '12 at 18:05 ...
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Safari 3rd party cookie iframe trick no longer working?

...ard tricks to get 3rd party cookies in Safari was as follows: use some javascript to POST to a hidden iframe. It (used to) trick Safari into thinking that the user had interacted with the 3rd party content and so then allow cookies to be set. ...
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How can I add a third button to an Android Alert Dialog?

The API says that the Alert Dialog can have one, two or three buttons, but the SDK only allows for a positive and negative button. How then can I add a third button? ...
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How to find the operating system version using JavaScript?

How can I find the OS name and OS version using JavaScript? 13 Answers 13 ...
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Why can I add named properties to an array as if it were an object?

... var myArray = Array(); myArray['A'] = "Athens"; myArray['B'] = "Berlin"; alert(myArray.length); This won't display '2', but '0' - effectively, no elements have been added to the array, just some new properties added to the array object. ...
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Disable browser's back button

... I came up with a little hack that disables the back button using JavaScript. I checked it on chrome 10, firefox 3.6 and IE9: <!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd"> <html xmlns="http://www.w3.org/1999/x...
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JavaScript click handler not working as expected inside a for loop [duplicate]

... (function (i) { $("#div" + i).click( function () { alert(i); } ); })(i); } UPDATE Updated DEMO Or you can use 'let' instead var to declare i. let gives you fresh binding each time. It can only be used in ECMAScript 6 strict mode. 'use strict'; for(let i=1; ...
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Convert SVG image to PNG with PHP

...ap.svg');?> </div> then changing the colors is as easy as: <script type="text/javascript" src="/path/to/jquery.js"></script> <script type="text/javascript"> $('#CA').css('fill', 'blue'); $('#NY').css('fill', '#ff0000'); </script> ...
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registerForRemoteNotificationTypes: is not supported in iOS 8.0 and later

...I have is the pre-release documentation: "Apps that use visible or audible alerts in conjunction with a local or push notification must register the types of alerts they employ." As to "why," I only have my interpretation: end-user convenience to not be bothered by messages, regardless of source. ...