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SqlDataAdapter vs SqlDataReader
...ver once
Is not as useful for updating back to the database
On the other hand, it:
Only has one record in memory at a time rather than an entire result set (this can be HUGE)
Is about as fast as you can get for that one iteration
Allows you start processing results sooner (once the first record is...
How best to determine if an argument is not sent to the JavaScript function
...ed' if one is paranoid (see comments).
Using the || operator has become standard practice - all the cool kids do it - but be careful: The default value will be triggered if the argument evaluates to false, which means it might actually be undefined, null, false, 0, '' (or anything else for which Bo...
Determine if string is in list in JavaScript
...EcmaScript 6
If you're using ES6, you can construct an array of the items, and use includes:
['a', 'b', 'c'].includes('b')
This has some inherent benefits over indexOf because it can properly test for the presence of NaN in the list, and can match missing array elements such as the middle one in [1...
Measuring execution time of a function in C++
... When I use this function, on first run it gave me 118440535 microseconds and on second run of the same function it gave me 83221031 microseconds. Shouldn't the two time measurements be equal when I am measuring the duration of that function only ?
– Xara
Mar ...
How to size an Android view based on its parent's dimensions
... layout. For example I have a RelativeLayout that fills the full screen, and I want a child view, say an ImageView , to take up the whole height, and 1/2 the width?
...
See :hover state in Chrome Developer Tools
...
Now you can see both the pseudo-class rules and force them on elements.
To see the rules like :hover in the Styles pane click the small :hov text in the top right.
To force an element into :hover state, right click it and select :hover.
Additional tips on the e...
BigDecimal setScale and round
...lluded to but not directly addressed is the difference between "precision" and "scale" and how they are used in the two statements. "precision" is the total number of significant digits in a number. "scale" is the number of digits to the right of the decimal point.
The MathContext constructor onl...
How SignalR works internally?
...connection. It gives you two programming models over that connection (hubs and persistent connections). SignalR has a concept of transports, each transport decides how data is sent/received and how it connects and disconnects.
SignalR has a few built in transports:
WebSockets
Server Sent Events
F...
How to print a dictionary's key?
...You have the keys() method, which gives you a python list of all the keys, and you have the iteritems() method, which returns key-value pairs, so
for key, value in mydic.iteritems() :
print key, value
Python 3 version:
for key, value in mydic.items() :
print (key, value)
So you have a ...
Instantiate and Present a viewController in Swift
I started taking a look of the new Swift on Xcode 6 , and I tried some demo projects and tutorials. Now I am stuck at:
1...