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PHP check whether property exists in object or class
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property_exists( mixed $class , string $property )
if (property_exists($ob, 'a'))
isset( mixed $var [, mixed $... ] )
if (isset($ob->a))
isset() will return false if property is null
Example 1:
$ob->a = null
var_dump(isset($ob->a)); // false
Example 2: ...
Is HTML5 localStorage asynchronous?
... of the HTML5 core standard, it's been split off.
The relevant (draft) specification can be found here and the one thing you'll notice is that it doesn't mention synchronous or asynchronous anywhere.
However, analysis of the text would suggest that it must be synchronous (my bold):
The setItem(key,...
How to run a shell script in OS X by double-clicking?
...ace
cd -- "$(dirname "$BASH_SOURCE")" right after the shebang line
or, if you must remain POSIX-compliant, cd -- "$(dirname "$0")".
For edge cases, such as finding a symlinked script's true source directory, see this answer of mine.
If the script is unexpectedly not executable:
Make it execu...
Java 8 Distinct by property
...rite:
persons.stream().filter(distinctByKey(Person::getName))
Note that if the stream is ordered and is run in parallel, this will preserve an arbitrary element from among the duplicates, instead of the first one, as distinct() does.
(This is essentially the same as my answer to this question: J...
Java, Classpath, Classloading => Multiple Versions of the same jar/project
...other frameworks/jars used in my project require. But all of them require different major versions like:
5 Answers
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How can you encode a string to Base64 in JavaScript?
...) accepts a “string” where each character represents an 8-bit byte – if you pass a string containing characters that can’t be represented in 8 bits, it will probably break. This isn’t a problem if you’re actually treating the string as a byte array, but if you’re trying to do something...
Can PNG image transparency be preserved when using PHP's GDlib imagecopyresampled?
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This solution, in my case GD works fine ONLY if PNG has a "regular" transparency area, like a surrounding transparent area, if it has a complex area, like with inner parts of the image with transparency, it always fails and puts black background, for example this image ...
MySQL check if a table exists without throwing an exception
What is the best way to check if a table exists in MySQL (preferably via PDO in PHP) without throwing an exception. I do not feel like parsing the results of "SHOW TABLES LIKE" et cetera. There must be some sort of boolean query?
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Convert string to title case with JavaScript
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If the jim-bob --> Jim-Bob is your desire, you should probably do /\b\w+/g. Example: str.replace(/\b\w+/g,function(s){return s.charAt(0).toUpperCase() + s.substr(1).toLowerCase();});
– vol7ron
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How can I update the current line in a C# Windows Console App?
...without having to extend a current line or go to a new line? For example, if I want to show a percentage representing how close a process is to completion, I'd just like to update the value on the same line as the cursor, and not have to put each percentage on a new line.
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