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How to check if a variable is not null?
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They are not equivalent. The first will execute the block following the if statement if myVar is truthy (i.e. evaluates to true in a conditional), while the second will execute the block if myVar is any value other than null.
The only values that are not truthy in JavaScript ...
How to simulate target=“_blank” in JavaScript
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Oh, I see. window.open is blocked by Firefox pop-up blocker, but target="_blank" isn't. Should I just ask the client to enable popups from their own website?
– Phillip Senn
Oct 15 '09 at 18:22
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Get hours difference between two dates in Moment Js
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Following code block shows how to calculate the difference in number of days between two dates using MomentJS.
var now = moment(new Date()); //todays date
var end = moment("2015-12-1"); // another date
var duration = moment.duration(now.di...
Catch multiple exceptions at once?
.... Write a common ErrorHandler function and, like, call it from each catch block.
If you ask me, the second example (with the if and is keywords) is both significantly less readable, and simultaneously significantly more error-prone during the maintenance phase of your project.
The maintenance pha...
node.js remove file
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What if I check it exists, but it's blocked by another process - or, I check it exists, and it's fine, but then another process randomly blocks it before I'm able to delete. How can I block straight after checking? then wouldnt I not be able to delete as its bl...
What is the difference between and ?
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<section> marks up a section, <div> marks up a generic block with no associated semantics.
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Adding a simple UIAlertView
... handler:nil]; //You can use a block here to handle a press on this button
[alertController addAction:actionOk];
[self presentViewController:alertController animated:YES completion:nil];
Swift 3 / 4 / 5:
let alertController = UIAlertController(title: "T...
Can Objective-C switch on NSString?
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You could set up a dictionary of blocks, like this:
NSString *lookup = @"Hearts"; // The value you want to switch on
typedef void (^CaseBlock)();
// Squint and this looks like a proper switch!
NSDictionary *d = @{
@"Diamonds":
^{
NSLog(@...
How do I get the current date in JavaScript?
... moment as if it were a language. Mine here uses the same common format as PHP: date.
Quick Links
Date.format.min.js 5.08 KB
dateFormat.min.js 4.16 KB
Flavor 1 new Date().format(String)
My Personal Fav. I know the taboo but works great on the Date Object. Just be aware of any other mods yo...
Change default text in input type=“file”?
... Bin</title>
</head>
<body>
<button style="display:block;width:120px; height:30px;" onclick="document.getElementById('getFile').click()">Your text here</button>
<input type='file' id="getFile" style="display:none">
</body>
</html>
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