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Getting exact error type in from DbValidationException
... string errorMessages = string.Join("; ", ex.EntityValidationErrors.SelectMany(x => x.ValidationErrors).Select(x => x.PropertyName + ": " + x.ErrorMessage));
throw new DbEntityValidationException(errorMessages);
}
}
This will overwrite your context's SaveChanges() method a...
Is there an IDictionary implementation that, on missing key, returns the default value instead of th
...<K, V>(this IDictionary<K, V> dict, K key, Func<V> defValSelector)
{
V value;
return dict.TryGetValue(key, out value) ? value : defValSelector();
}
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No Main() in WPF?
... in visual studio. Use the navigation bar > Method drop down list > select Main (greyed out). This takes you to App.g.i.cs.
– P.Brian.Mackey
Apr 6 '18 at 15:58
add a c...
What is the point of Lookup?
...in those assemblies
IEnumerable<Type> allTypes = sampleTypes.Select(t => t.Assembly)
.SelectMany(a => a.GetTypes());
// Grouped by namespace, but indexable
ILookup<string, Type> lookup = allTypes.ToLookup(t =&g...
What does the double colon (::) mean in CSS?
...
It means pseudo element selector. It means the element to the right doesn't exist in the normal DOM, but can be selected.
A pseudo-element is made of two colons (::) followed by the name of the pseudo-element.
Source
It was originally only a ...
How to check if activity is in foreground or in visible background?
...stem dialogue box pops-up and I only want to finish() ; once the user has selected an option from the dialogue box?
23 An...
How to change the name of the active scheme in Xcode?
...t Scheme" from the "Product" menu.
Click on the "Manage Schemes…" button
Select the scheme whose name you wish to change
Press the "Return" key
It will select the name of the scheme and allow you to edit it.
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How to speed up insertion performance in PostgreSQL
...rypto module) is (a lot) faster than uuid_generate_v4()
=# explain analyze select uuid_generate_v4(),* from generate_series(1,10000);
QUERY PLAN
---------------------------------------------------------------------------------------------------...
How to reset or change the MySQL root password?
...qld]
skip-grant-tables
sudo service mysql restart
mysql -u root
use mysql
select * from mysql.user where user = 'root'; - Look at the top to determine whether the password column is called
password or authentication_string
UPDATE mysql.user set *password_field from above* = PASSWORD('your_new_passw...
Proper use of 'yield return'
...ng when one filter the stream (with where), or eventually process it (with select not being select(o => o)).
– Soleil - Mathieu Prévot
Sep 14 at 13:06
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