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Checking if a key exists in a JavaScript object?
...r, if you want to particularly test for properties of the object instance (and not inherited properties), use hasOwnProperty:
obj.hasOwnProperty("key") // true
For performance comparison between the methods that are in, hasOwnProperty and key is undefined, see this benchmark
...
Detect when browser receives file download
...lution uses JavaScript on the client.
The client algorithm:
Generate a random unique token.
Submit the download request, and include the token in a GET/POST field.
Show the "waiting" indicator.
Start a timer, and every second or so, look for a cookie named "fileDownloadToken" (or whatever you dec...
Download data url file
...ess from a browser. They can just drag their zip directly into the browser and it'll let them download all the files within. They can also create new zip files by dragging individual files in.
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What's the cause of this FatalExecutionEngineError in .NET 4.5 beta? [closed]
...ecutionEngineError exception. I spent a good 30 minutes trying to isolate and minimize the culprit sample. Compile this using Visual Studio 2012 as a console app:
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How to use JavaScript source maps (.map files)?
...js.map extension shipped with some JavaScript libraries (like Angular ), and that just raised few questions in my head:
5...
How can I use jQuery in Greasemonkey?
...bes for manually adding a script element to the page.
Between version 0.8 and 0.9, @require is only processed when the script is first installed. If you change the list of required scripts, you need to uninstall your script and reinstall it; Greasemonkey downloads the required script once at instal...
'innerText' works in IE, but not in Firefox
...
Firefox uses the W3C-compliant textContent property.
I'd guess Safari and Opera also support this property.
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SQL Data Reader - handling Null column values
...der.GetString(indexFirstName);
}
That's your only reliable way to detect and handle this situation.
I wrapped those things into extension methods and tend to return a default value if the column is indeed null:
public static string SafeGetString(this SqlDataReader reader, int colIndex)
{
if(!...
Implementing comparison operators via 'tuple' and 'tie', a good idea?
(Note: tuple and tie can be taken from Boost or C++11.)
When writing small structs with only two elements, I sometimes tend to choose a std::pair , as all important stuff is already done for that datatype, like operator< for strict-weak-ordering.
The downsides though are the pretty much us...
Type safety: Unchecked cast
...g it to HashMap directly would not cause the problem with the second case (and perhaps there would not be a warning in the first case, I'm not sure how pedantic the Java compiler is with warnings for Java 5). However, you are converting it to a HashMap<String, String>.
HashMaps are really map...