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UTF-8: General? Bin? Unicode?
...
In general, utf8_general_ci is faster than utf8_unicode_ci, but less correct.
Here is the difference:
For any Unicode character set, operations performed using the _general_ci collation are faster than those for the _unicode_ci collatio...
In where shall I use isset() and !empty()
.....) contains some non-empty data.
To answer question 1 :
$str = '';
var_dump(isset($str));
gives
boolean true
Because the variable $str exists.
And question 2 :
You should use isset to determine whether a variable exists ; for instance, if you are getting some data as an array, you migh...
How to read if a checkbox is checked in PHP?
...="value1">
After submitting the form you can check it with:
isset($_POST['test'])
or
if ($_POST['test'] == 'value1') ...
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How do I filter ForeignKey choices in a Django ModelForm?
...e fields named directly.
form.rate.queryset = Rate.objects.filter(company_id=the_company.id)
If you take the default ModelForm object, form.fields["rate"].queryset = ...
This is done explicitly in the view. No hacking around.
...
Constructor overload in TypeScript
... Box(params) {
if (params === void 0) { params = {}; }
var _a = params.x, x = _a === void 0 ? 0 : _a, _b = params.y, y = _b === void 0 ? 0 : _b, _c = params.height, height = _c === void 0 ? 1 : _c, _d = params.width, width = _d === void 0 ? 1 : _d;
this.x = x;
this.y ...
append multiple values for one key in a dictionary [duplicate]
...st of values associated with that year, right? Here's how I'd do it:
years_dict = dict()
for line in list:
if line[0] in years_dict:
# append the new number to the existing array at this slot
years_dict[line[0]].append(line[1])
else:
# create a new array in this slo...
Iterate two Lists or Arrays with one ForEach statement in C#
...ic class Pair<TFirst, TSecond>
{
private readonly TFirst _first;
private readonly TSecond _second;
private int _hashCode;
public Pair(TFirst first, TSecond second)
{
_first = first;
_second = second;
}
public...
Javascript Drag and drop for touch devices [closed]
...aggable items and it works great so far.
if (event.target.id == 'draggable_item' ) {
event.preventDefault();
}
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How to filter NSFetchedResultsController (CoreData) with UISearchDisplayController/UISearchBar
...s for this example
NSFetchedResultsController *fetchedResultsController_;
NSFetchedResultsController *searchFetchedResultsController_;
NSManagedObjectContext *managedObjectContext_;
// The saved state of the search UI if a memory warning removed the view.
NSString *savedS...
Why does this go into an infinite loop?
...mpiled bytecode, as produced by javap -c, with my comments):
8: iload_1 // Remember current value of x in the stack
9: iinc 1, 1 // Increment x (doesn't change the stack)
12: istore_1 // Write remebered value from the stack to x
For comparison, x = ++x:
8: ...