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What is the use of ObservableCollection in .net?
...ed,
INotifyPropertyChanged
As such it is very useful when you want to know when the collection has changed. An event is triggered that will tell the user what entries have been added/removed or moved.
More importantly they are very useful when using databinding on a form.
...
How does the paste image from clipboard functionality work in Gmail and Google Chrome 12+?
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Now that the first item in the list isn't always the file you pasted, I've updated it to loop through the items to find any pasted files.
– Nick Retallack
Sep 7 '15 at 20:28
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How do I uniquely identify computers visiting my web site?
... code snippet. This document does not show how to implement it. I want to know how do I implement this so I can track unique users for my site.
– Oliver
Jul 27 '17 at 8:16
12
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How to convert local time string to UTC?
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NOTE -- As of 2020 you should not be using .utcnow() or .utcfromtimestamp(xxx). As you've presumably moved on to python3,you should be using timezone aware datetime objects.
>>> from datetime import timezone
>>> dt_now = datetime.now(tz=timezone.utc)
&g...
JavaScript get clipboard data on paste event (Cross browser)
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The situation has changed since writing this answer: now that Firefox has added support in version 22, all major browsers now support accessing the clipboard data in a paste event. See Nico Burns's answer for an example.
In the past this was not generally possible in a cross-b...
C++ equivalent of java's instanceof
...seClass>(ptr)) { ... }
However, this purely operates on the types as known by the compiler.
Edit:
This code should work for polymorphic pointers:
template<typename Base, typename T>
inline bool instanceof(const T *ptr) {
return dynamic_cast<const Base*>(ptr) != nullptr;
}
E...
JavaScript function order: why does it matter?
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var foo = 42;
//the interpreter turns it into this:
var foo;
foo = 42;
Now, how function declarations are handled:
var foo = 42;
function bar() {}
//turns into
var foo; //Insanity! It's now at the top
function bar() {}
foo = 42;
The var statements "throws" the creation of foo to the very top...
Is D a credible alternative to Java and C++? [closed]
... see of D, by all means, learn it - it shouldn't take long if you already know Java and C++. I don't think evangelism would be helpful - at this point if D is going to succeed, what it really needs is more people quietly using it and addressing its major shortcomings like standard library and IDE s...
How to programmatically send SMS on the iPhone?
Does anybody know if it's possible, and how, to programmatically send a SMS from the iPhone , with the official SDK / Cocoa Touch?
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How to write iOS app purely in C
...plicationMain(int, ...);
// Entry point of the application. If you don't know what this is by now,
// then you probably shouldn't be reading the rest of this post.
int main(int argc, char *argv[])
{
// Create an @autoreleasepool, using the old-stye API.
// Note that while NSAutoreleasePoo...