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Django filter versus get for single object?
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get() is provided specifically for this case. Use it.
Option 2 is almost precisely how the get() method is actually implemented in Django, so there should be no "performance" difference (and the fact that you're thinking about it indicates you're...
@Html.BeginForm Displaying “System.Web.Mvc.Html.MvcForm” on Page
I have a razor view that I added a delete button to inside of an 'if' statement and when the view is rendered in the browser it is displaying "System.Web.Mvc.Html.MvcForm" next to the delete button.
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Call an activity method from a fragment
...ctivity to fragment:
FragmentManager fm = getSupportFragmentManager();
//if you added fragment via layout xml
YourFragmentClass fragment = (YourFragmentClass)fm.findFragmentById(R.id.your_fragment_id);
fragment.yourPublicMethod();
If you added fragment via code and used a tag string when you add...
Groovy / grails how to determine a data type?
...ss()
You can abbreviate this to someObject.class in most cases. However, if you use this on a Map it will try to retrieve the value with key 'class'. Because of this, I always use getClass() even though it's a little longer.
If you want to check if an object implements a particular interface or e...
Why does the C++ map type argument require an empty constructor when using []?
...ns a reference to the object
that is associated with a particular
key. If the map does not already
contain such an object, operator[]
inserts the default object
data_type().
If you don't have default constructor you can use insert/find functions.
Following example works fine:
myMap.inse...
Hide/Show Column in an HTML Table
...faster than any JS loop approach; for really long tables it can make a significant difference to responsiveness.
If you can get away with not supporting IE6, you could use adjacency selectors to avoid having to add the class attributes to tds. Or alternatively, if your concern is making the markup ...
delete vs delete[] operators in C++
What is the difference between delete and delete[] operators in C++?
7 Answers
7
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When do I use the PHP constant “PHP_EOL”?
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From main/php.h of PHP version 7.1.1 and version 5.6.30:
#ifdef PHP_WIN32
# include "tsrm_win32.h"
# include "win95nt.h"
# ifdef PHP_EXPORTS
# define PHPAPI __declspec(dllexport)
# else
# define PHPAPI __declspec(dllimport)
# endif
# define PHP_DIR_SEPARATOR ...
How to sum all column values in multi-dimensional array?
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If there are n arrays?
– Muhammad Usman
Apr 16 '14 at 13:51
2
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Rails: Adding an index after adding column
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If you need to create a user_id then it would be a reasonable assumption that you are referencing a user table. In which case the migration shall be:
rails generate migration AddUserRefToProducts user:references
This comma...