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What's the difference(s) between .ToList(), .AsEnumerable(), AsQueryable()?
...or example, we need to use one of our own methods in a query we would typically write something like
var query = context.Observations.Select(o => o.Id)
.AsEnumerable().Select(x => MySuperSmartMethod(x))
ToList – which converts an IEnumerable<T> to a List<T> ...
Convert SVG image to PNG with PHP
I'm working on a web project that involves a dynamically generated map of the US coloring different states based on a set of data.
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What's the difference between IQueryable and IEnumerable
...;>), which can be thought of as "is the 'Age' property > 18".
This allows things like LINQ-to-SQL to exist because they can parse the expression tree and convert it into equivalent SQL. And because the provider doesn't need to execute until the IQueryable is enumerated (it implements IEnum...
Comparing mongoose _id and strings
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The accepted answers really limit what you can do with your code. For example, you would not be able to search an array of Object Ids by using the equals method. Instead, it would make more sense to always cast to string and compare the keys.
Her...
How to remove item from list in C#?
...== 2);
resultList.Remove(itemToRemove);
When you are not sure the item really exists you can use SingleOrDefault. SingleOrDefault will return null if there is no item (Single will throw an exception when it can't find the item). Both will throw when there is a duplicate value (two items with the s...
The relationship could not be changed because one or more of the foreign-key properties is non-nulla
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You should delete old child items thisParent.ChildItems one by one manually. Entity Framework doesn't do that for you. It finally cannot decide what you want to do with the old child items - if you want to throw them away or if you want to keep and assign them to other parent entities. You must ...
Linq style “For Each” [duplicate]
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Calling ToList followed by ForEach involves iterating through the original collection twice. I'd prefer a standard foreach loop any day: less typing, more readable and better performance: foreach (var x in someValues) list.Add...
Use StringFormat to add a string to a WPF XAML binding
... number and units isn't fixed. <Run Text="{x:Static s:UIStrings.General_FahrenheitAbbreviation}" />
– Matt Becker
Nov 10 '15 at 15:19
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Java Name Hiding: The Hard Way
... of working with the reflection API.
The downside is that this code is really horrible! For me, it generates a warning, and that's a good thing in general. But since it's working around a problem that is otherwise thoroughly impractical, adding a
@SuppressWarnings("static-access")
at an approp...
equals vs Arrays.equals in Java
... it, ever.
That said, it's not "broken" as in "someone has done it in a really wrong way" — it's just doing what's defined and not what's usually expected. So for purists: it's perfectly fine, and that also means, don't use it, ever.
Now the expected behaviour for equals is to compare data. The ...