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How to calculate the difference between two dates using PHP?
... up to date solution see jurka's answer below
You can use strtotime() to convert two dates to unix time and then calculate the number of seconds between them. From this it's rather easy to calculate different time periods.
$date1 = "2007-03-24";
$date2 = "2009-06-26";
$diff = abs(strtotime($date...
In C#, why is String a reference type that behaves like a value type?
...rence, rather than primitive, type. Plus, if string were a value type then converting it to object would require it to be boxed, a needless inefficiency).
– Qwertie
Jun 25 '10 at 15:50
...
What is the difference between “px”, “dip”, “dp” and “sp”?
...
I will elaborate more on how exactly does dp convert to px:
If running on an mdpi device, a 150 x 150 px image will take up 150 * 150 dp of screen space.
If running on an hdpi device, a 150 x 150 px image will take up 100 * 100 dp of screen space.
If running on an xhd...
What is std::move(), and when should it be used?
...ically a function - I would say it isn't really a function. It's sort of a converter between ways the compiler considers an expression's value.
2. "What does it do?"
The first thing to note is that std::move() doesn't actually move anything. It changes an expression from being an lvalue (such as a n...
Append values to query string
...h can cause issues with internationalization as special characters will be converted to their unicode equivalents in the query.ToString() method.
– tezromania
Nov 11 '14 at 17:05
...
Performance surprise with “as” and nullable types
...e when unboxing nullable value types. Because Nullable<T> values are converted to boxed Ts during the box operation, an implementation often must manufacture a new Nullable<T> on the heap and compute the address to the newly allocated object.
...
How should you build your database from source control?
... I'm assuming "look up lists" means the data that is used to populuate <select> boxes? That may not always be possible, since that data might be modified by users (in some way) on production. Keeping backups makes sense in this case. You also suggest recreating the database from scratch as ...
How to have favicon / icon set when bookmarklet dragged to toolbar?
...for your bookmarklet.
Open Bookmarks Manager, click Organize dropdown, and select Export, save your bookmarks as html file.
Open that html file in text editor.
Find the bookmark you just created, lets say its Gmail bookmark, you should have an html code for it, that looks like this:
<DT><...
What are the best PHP input sanitizing functions?
... much more thorough job of both stripping out all HTML and also allowing a selective whitelist of tags and attributes through.
Modern PHP versions ship with the filter extension, which provides a comprehensive way to sanitize user input.
Validation
Making sure that submitted data is free from unexpe...
arrayfun can be significantly slower than an explicit loop in matlab. Why?
...ance is quite good now, and if you need cell as output, you do not need to convert your matrix after you have used the fully vectorized solution.
So why is arrayfun slower than a simple loop structure? Unfortunately, it is impossible for us to say for sure, since there is no source code available. ...