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How can I prevent SQL injection in PHP?
...ction->prepare('SELECT * FROM employees WHERE name = ?');
$stmt->bind_param('s', $name); // 's' specifies the variable type => 'string'
$stmt->execute();
$result = $stmt->get_result();
while ($row = $result->fetch_assoc()) {
// Do something with $row
}
If you're connecting...
How to extract the n-th elements from a list of tuples?
...htly slower than the list comprehension:
setup = 'elements = [(1,1,1) for _ in range(100000)];from operator import itemgetter'
method1 = '[x[1] for x in elements]'
method2 = 'map(itemgetter(1), elements)'
import timeit
t = timeit.Timer(method1, setup)
print('Method 1: ' + str(t.timeit(100)))
t = t...
Getting the current page
...ewController: UIScrollViewDelegate {
func scrollViewDidEndDecelerating(_ scrollView: UIScrollView) {
let width = scrollView.frame.width
let page = Int(round(scrollView.contentOffset.x/width))
print("CurrentPage:\(page)")
}
}
...
Memoization in Haskell?
...alling, for example: fix f 123 = 144
We could memoize this by defining:
f_list :: [Int]
f_list = map (f faster_f) [0..]
faster_f :: Int -> Int
faster_f n = f_list !! n
That performs passably well, and replaces what was going to take O(n^3) time with something that memoizes the intermediate r...
Why does modern Perl avoid UTF-8 by default?
...???????????????????????????????????????????????????????????
Set your PERL_UNICODE envariable to AS. This makes all Perl scripts decode @ARGV as UTF‑8 strings, and sets the encoding of all three of stdin, stdout, and stderr to UTF‑8. Both these are global effects, not lexical ones.
At the top o...
Insert into … values ( SELECT … FROM … )
...SERT from another table I did the following in SQLite3:
INSERT INTO column_1 ( val_1, val_from_other_table )
VALUES('val_1', (SELECT val_2 FROM table_2 WHERE val_2 = something))
share
|
improve ...
/bin/sh: pushd: not found
... If it's just a oneliner, the following may also work (cd /new_path ; command )
– barney765
Aug 5 '17 at 7:31
...
Read error response body in Java
...ere is to code like this:
HttpURLConnection httpConn = (HttpURLConnection)_urlConnection;
InputStream _is;
if (httpConn.getResponseCode() < HttpURLConnection.HTTP_BAD_REQUEST) {
_is = httpConn.getInputStream();
} else {
/* error from server */
_is = httpConn.getErrorStream();
}
...
How do I get an animated gif to work in WPF?
...e gif has 10 frames per second.
class GifImage : Image
{
private bool _isInitialized;
private GifBitmapDecoder _gifDecoder;
private Int32Animation _animation;
public int FrameIndex
{
get { return (int)GetValue(FrameIndexProperty); }
set { SetValue(FrameIndexProp...
Get path of executable
...
The boost::dll::program_location function is one of the best cross platform methods of getting the path of the running executable that I know of. The DLL library was added to Boost in version 1.61.0.
The following is my solution. I have tested it ...