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.NET - Dictionary locking vs. ConcurrentDictionary
...all hell would break loose. Or, what if two customers reaches for the same item at the same time, who wins? Will there be a fight? This is a non-threadsafe-collection. There's plenty of ways to avoid problems, but they all require some kind of locking, or rather explicit access in some way or anothe...
When saving, how can you check if a field has changed?
...
Best way is with a pre_save signal. May not have been an option back in '09 when this question was asked and answered, but anyone seeing this today should do it this way:
@receiver(pre_save, sender=MyModel)
def do_something_...
Is it possible to deserialize XML into List?
...on;
[XmlRoot("user_list")]
public class UserList
{
public UserList() {Items = new List<User>();}
[XmlElement("user")]
public List<User> Items {get;set;}
}
public class User
{
[XmlElement("id")]
public Int32 Id { get; set; }
[XmlElement("name")]
public String...
Check for null in foreach loop
... @kjbartel's answer (at " stackoverflow.com/a/32134295/401246 " is the best solution, because it doesn't: a) involve performance degradation of (even when not null) degenerating the whole loop to LCD of IEnumerable<T> (as using ?? would), b) require adding an Extension Method to every Proj...
Get file version in PowerShell
...omefilepath").FileVersion
Or as noted here on a list of files:
get-childitem * -include *.dll,*.exe | foreach-object { "{0}`t{1}" -f $_.Name, [System.Diagnostics.FileVersionInfo]::GetVersionInfo($_).FileVersion }
Or even nicer as a script: https://jtruher3.wordpress.com/2006/05/14/powershell-an...
Check if item is in an array / list
...
Assuming you mean "list" where you say "array", you can do
if item in my_list:
# whatever
This works for any collection, not just for lists. For dictionaries, it checks whether the given key is present in the dictionary.
...
Moving UITabBarItem Image down?
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Best of all the answers...Thank you so much @Neil Galiaskarov
– Venkatesh Chejarla
Nov 23 '18 at 12:07
...
Determine if a sequence contains all elements of another sequence using Linq [duplicate]
...ing adding your extension method with the Except implementation to get the best of both worlds.
– Bryan Watts
Nov 21 '11 at 17:00
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show 2 m...
How to explain callbacks in plain english? How are they different from calling one function from ano
...er, the callback_funct will return 6 as result. Read this callbackhell.com best source I found.
– Dung
Nov 1 '17 at 10:03
...
Adding options to a using jQuery?
... text: 'My option'
}));
If you're adding options from a collection of items, you can do the following:
$.each(items, function (i, item) {
$('#mySelect').append($('<option>', {
value: item.value,
text : item.text
}));
});
...