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Checking if a key exists in a JavaScript object?
... testing whether a key exists. What if the key exists but the value is actually undefined?
var obj = { key: undefined };
obj["key"] !== undefined // false, but the key exists!
You should instead use the in operator:
"key" in obj // true, regardless of the actual value
If you want to check if a...
What is the use of hashCode in Java?
...
Buckets aside, hashcode is a method that the object calls to determine the order to store each object in memory. If objects are equal, then their hashcode must also be equal. (converse of this statement is false)
– NoName
Jun 24 '17 at 6:1...
How to copy data to clipboard in C#
...ading.ThreadStateException is here with my code that worked correctly with all browsers:
Thread thread = new Thread(() => Clipboard.SetText("String to be copied to clipboard"));
thread.SetApartmentState(ApartmentState.STA); //Set the thread to STA
thread.Start();
thread.Join();
credits to thi...
How does Task become an int?
...t; (for a logical result of type T in an async manner)
The compiler does all the appropriate wrapping. The point is that you're asynchronously returning urlContents.Length - you can't make the method just return int, as the actual method will return when it hits the first await expression which ha...
Is there a cross-domain iframe height auto-resizer that works?
...to their content. It uses the PostMessage and MutationObserver APIs, with fall backs for IE8-10. It also has options for the content page to request the containing iFrame is a certain size and can also close the iFrame when your done with it.
https://github.com/davidjbradshaw/iframe-resizer
2. Use E...
Easiest way to flip a boolean value?
...ses can be merged as they do the same thing.
– David Allan Finch
Mar 4 '09 at 15:16
1
Is default:...
What is the difference between canonical name, simple name and class name in Java Class?
...upshot looking at this is:
the name is the name that you'd use to dynamically load the class with, for example, a call to Class.forName with the default ClassLoader. Within the scope of a certain ClassLoader, all classes have unique names.
the canonical name is the name that would be used in an im...
HTML input textbox with a width of 100% overflows table cells
... the input with two divs, the outer has a 3px margin (which makes it 3px smaller than the td), the inner has a 3px padding. This makes the input 6px smaller than the td, which is what you wanted to begin with.
I am not sure about the mechanics of this, but it works.
In this simple example, it a...
Integrated Markdown WYSIWYG text editor
...this (check out http://nightly-v4.ckeditor.com/3737/samples/bbcode.html).
All you have to do is implement this interface http://nightly-v4.ckeditor.com/ckeditor_api/#!/api/CKEDITOR.dataProcessor. If you check BBCode plugin's code you'll see some hacks and tricks, because unfortunately current CKEdi...
Working with time DURATION, not time of day
... cell B2 and drag as far down as the A column goes to apply the formula to all data in col A.
Last step, be sure to highlight all of column B and set it to Number format (the application of the formula may have automatically set format to Time).
...