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How do you convert a byte array to a hexadecimal string, and vice versa?
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You're using SubString. Doesn't this loop allocate a horrible amount of string objects?
– Wim Coenen
Mar 6 '09 at 16:36
30
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java.sql.SQLException: Incorrect string value: '\xF0\x9F\x91\xBD\xF0\x9F…'
...ead:
For a supplementary character, utf8 cannot store the character at all,
while utf8mb4 requires four bytes to store it. Since utf8 cannot store
the character at all, you do not have any supplementary characters in
utf8 columns and you need not worry about converting characters or
losi...
Python integer incrementing with ++ [duplicate]
...I've looked back at my VB6 days and thought, "What modern language doesn't allow incrementing with double plus signs?":
7 A...
Django set field value after a form is initialized
...value after the form was submitted, you can use something like:
if form.is_valid():
form.cleaned_data['Email'] = GetEmailString()
Check the referenced docs above for more on using cleaned_data
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Should I use 'has_key()' or 'in' on Python dicts?
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in is definitely more pythonic.
In fact has_key() was removed in Python 3.x.
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How to sort an array by a date property
...e a custom non-enumerable sortBy function using a Schwartzian transform on all arrays :
(function(){
if (typeof Object.defineProperty === 'function'){
try{Object.defineProperty(Array.prototype,'sortBy',{value:sb}); }catch(e){}
}
if (!Array.prototype.sortBy) Array.prototype.sortBy = sb;
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Select between two dates with Django
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Use the __range operator:
...filter(current_issue__isnull=True, created_at__range=(start_date, end_date))
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Dictionary returning a default value if the key does not exist [duplicate]
...Value(key, out value);
and just ignore the return value. However, that really will just return default(TValue), not some custom default value (nor, more usefully, the result of executing a delegate). There's nothing more powerful built into the framework. I would suggest two extension methods:
pu...
Handling applicationDidBecomeActive - “How can a view controller respond to the app becoming Active?
...tionDidBecomeActiveNotification and specify which method that you want to call when that notification gets sent to your application.
[[NSNotificationCenter defaultCenter] addObserver:self
selector:@selector(someMethod:)
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When to use symbols instead of strings in Ruby?
...iers. For Ruby < 2.2 only use symbols when they aren't generated dynamically, to avoid memory leaks.
Full answer
The only reason not to use them for identifiers that are generated dynamically is because of memory concerns.
This question is very common because many programming languages don't h...