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Is there a reason for C#'s reuse of the variable in a foreach?
... methods in C#, we have to be wary of the access to modified closure pitfall. For example:
4 Answers
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How to solve the error LNK2019: unresolved external symbol - function?
...l but have not declared that class itself as import/export.
#ifdef MYDLL_EXPORTS
#define DLLEXPORT __declspec(dllexport)
#else
#define DLLEXPORT __declspec(dllimport)
#endif
class DLLEXPORT Book // <--- this class must also be declared as export/import
{
public:
Book();
...
Are there disadvantages to using a generic varchar(255) for all text-based fields?
...stcode , first name , last name , town , country , phone number etc, all of which are defined as VARCHAR(255) even though none of these fields will ever come close to having 255 characters. (If you're wondering, it's this way because Ruby on Rails migrations map String fields to VARCHAR(25...
appending array to FormData and send via AJAX
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add all type inputs to FormData
const formData = new FormData();
for (let key in form) {
Array.isArray(form[key])
? form[key].forEach(value => formData.append(key + '[]', value))
: formData.append(key, for...
What's the best practice for primary keys in tables?
...
I follow a few rules:
Primary keys should be as small as necessary. Prefer a numeric type because numeric types are stored in a much more compact format than character formats. This is because most primary keys will be foreign keys in another table as well as used in multipl...
Avoid synchronized(this) in Java?
...il code may steal your lock (very popular this one, also has an
"accidentally" variant)
I'm more worried about accidentally. What it amounts to is that this use of this is part of your class' exposed interface, and should be documented. Sometimes the ability of other code to use your lock is d...
Coffeescript — How to create a self-initiating anonymous function?
... XåpplI'-I0llwlg'I -XåpplI'-I0llwlg'I -
17.9k2323 gold badges9595 silver badges143143 bronze badges
add a c...
JavaScript post request like a form submit
...y: post('/contact/', {name: 'Johnny Bravo', csrfmiddlewaretoken: $("#csrf_token").val()});
– Davidson Lima
Nov 22 '17 at 16:09
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Detect if the app was launched/opened from a push notification
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I am getting the call to application:didReceiveRemoteNotification: after tapping the notification regardless of whether the app is just in the background or not running at all so this answer suits my needs perfectly. Tested on iOS 7 & 8
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Using multiple arguments for string formatting in Python (e.g., '%s … %s')
...swered Jul 18 '14 at 17:49
Lordn__nLordn__n
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