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Handling specific errors in JavaScript (think exceptions)
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To create custom exceptions, you can inherit from the Error object:
function SpecificError () {
}
SpecificError.prototype = new Error();
// ...
try {
throw new SpecificError;
} catch (e) {
if (e instanceof SpecificError) {
// specific error
} else {
...
Find a value anywhere in a database
Given a #, how do I discover in what table and column it could be found within?
18 Answers
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How do you migrate an IIS 7 site to another server?
I'm wondering what is the best practice for moving a website to another server (along with all settings, etc.)
7 Answers
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How to validate a url in Python? (Malformed or not)
I have url from the user and I have to reply with the fetched HTML.
10 Answers
10
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CSS center text (horizontally and vertically) inside a div block
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If it is one line of text and/or image, then it is easy to do. Just use:
text-align: center;
vertical-align: middle;
line-height: 90px; /* The same as your div height */
That's it. If it can be multiple lines, then it i...
Alternatives to dispatch_get_current_queue() for completion blocks in iOS 6?
...appealing, but ultimately not a great idea. That queue could be a low priority queue, the main queue, or some other queue with odd properties.
My favorite approach to this is to say "the completion block runs on an implementation defined queue with these properties: x, y, z", and let the block disp...
How do I remove  from the beginning of a file?
I have a CSS file that looks fine when I open it using gedit , but when it's read by PHP (to merge all the CSS files into one), this CSS has the following characters prepended to it: 
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Does PNG contain EXIF data like JPG?
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Edit: Version 1.5.0 (July 2017) of the Extensions to the PNG 1.2 Specification has finally added an EXIF chunk. It remains to be seen if encoders-decoders begin to support it.
Original: PNG does not embed EXIF info. It allows,...
How do I control how Emacs makes backup files?
...erywhere and I don't like having to remember to delete them. Also, if I edit a file that has a hard link somewhere else in the file system, the hard link points to the backup when I'm done editing, and that's confusing and awful. How can I either eliminate these backup files, or have them go somew...
Insert line break inside placeholder attribute of a textarea?
...e', 'This is a line \nthis should be a new line');
Then you could remove it on focus and apply it back (if empty) on blur. Something like this
var placeholder = 'This is a line \nthis should be a new line';
$('textarea').attr('value', placeholder);
$('textarea').focus(function(){
if($(this)...