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Difference between decimal, float and double in .NET?
... | | | with 28 or 29 significant figures |
| char | System.Char | N/A | 2 | Any Unicode character (16 bit) |
| bool | System.Boolean | N/A | 1 / 2 | true or false |
+---------+----------------+-------...
Efficient string concatenation in C++
...tor+ is not efficient:
Take a look at this interface:
template <class charT, class traits, class Alloc>
basic_string<charT, traits, Alloc>
operator+(const basic_string<charT, traits, Alloc>& s1,
const basic_string<charT, traits, Alloc>& s2)
You can see t...
How to get the data-id attribute?
...e info here">My Awesome Div</div>
JS
var myDiv = document.querySelector('#my-div');
myDiv.dataset.info // "some info here"
myDiv.dataset.otherInfo // "more info here"
Demo: http://html5demos.com/dataset
Full browser support list: http://caniuse.com/#feat=dataset
...
How do I check if an index exists on a table field in MySQL?
...
Try:
SELECT * FROM information_schema.statistics
WHERE table_schema = [DATABASE NAME]
AND table_name = [TABLE NAME] AND column_name = [COLUMN NAME]
It will tell you if there is an index of any kind on a certain column wi...
How to split one string into multiple strings separated by at least one space in bash shell?
...[*] [a] [*]. Only use it if you are 101% sure that there are no SHELL metacharacters in the splitted string!
– Tino
May 13 '15 at 10:03
4
...
Multiple Updates in MySQL
... another useful option is not yet mentioned:
UPDATE my_table m
JOIN (
SELECT 1 as id, 10 as _col1, 20 as _col2
UNION ALL
SELECT 2, 5, 10
UNION ALL
SELECT 3, 15, 30
) vals ON m.id = vals.id
SET col1 = _col1, col2 = _col2;
...
Tri-state Check box in HTML?
...lternative would be to play with the checkbox transparency
for the "some selected" state (as Gmail does used to
do in previous versions). It will require some javascript and a CSS
class. Here I put a particular example that handles a list with
checkable items and a checkbox that allows to se...
What is the difference between an int and an Integer in Java and C#?
...nt is not an object.
int is one of the few primitives in Java (along with char and some others). I'm not 100% sure, but I'm thinking that the Integer object more or less just has an int property and a whole bunch of methods to interact with that property (like the toString() method for example). So...
How can I select an element by name with jQuery?
...
You can use the jQuery attribute selector:
$('td[name ="tcol1"]') // matches exactly 'tcol1'
$('td[name^="tcol"]' ) // matches those that begin with 'tcol'
$('td[name$="tcol"]' ) // matches those that end with 'tcol'
$('td[name*="tcol"]' ) // matche...
Measuring execution time of a function in C++
...ypedef std::string String;
//first test function doing something
int countCharInString(String s, char delim){
int count=0;
String::size_type pos = s.find_first_of(delim);
while ((pos = s.find_first_of(delim, pos)) != String::npos){
count++;pos++;
}
return count;
}
//sec...