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linq query to return distinct field values from a list of objects
... it's easy - project to that with Select and then use the normal Distinct call.)
In MoreLINQ we have the DistinctBy operator which you could use:
var distinct = list.DistinctBy(x => x.typeID);
This only works for LINQ to Objects though.
You can use a grouping or a lookup, it's just somewhat ...
How to find the array index with a value?
...code marked as the correct answer but it seems that that code wont work in all versions of IE. This answer works in all versions of IE but I changed the code slightly: var arrayPosition = $.inArray( value, Array ); works perfectly
– James Blackburn
Dec 13 '13 ...
Optional query string parameters in ASP.NET Web API
...ect using [FromUri] doesn't directly answer the original question. It basically says populate these models with the values from the Uri. The models properties would need to be nullable or a reference type in order for them to support being optional. Added additional information.
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How do I preview emails in Rails?
...iables the template expects.
This could be done with fixtures, but I typically prefer to just grab some pseudo-random real data. Remember - this is NOT a unit test - this is purely a development aid. It doesn't need to produce the same result every single time - in fact - it's probably better if ...
Correct way to close nested streams and writers in Java [duplicate]
...
I usually do the following. First, define a template-method based class to deal with the try/catch mess
import java.io.Closeable;
import java.io.IOException;
import java.util.LinkedList;
import java.util.List;
public abstract cl...
C++ new int[0] — will it allocate memory?
... When the value of the expression in a direct-new-declarator is zero, the allocation function is called to allocate an array with no elements.
From 3.7.3.1/2
The effect of dereferencing a pointer returned as a request for zero size is undefined.
Also
Even if the size of the space reques...
When to use .First and when to use .FirstOrDefault with LINQ?
I've searched around and haven't really found a clear answer as to when you'd want to use .First and when you'd want to use .FirstOrDefault with LINQ.
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Rails params explained?
...e "1" and params[:boo] would be "octopus".
In HTTP/HTML, the params are really just a series of key-value pairs where the key and the value are strings, but Ruby on Rails has a special syntax for making the params be a hash with hashes inside. For example, if the user's browser requested
http://w...
Error when trying to obtain a certificate: The specified item could not be found in the keychain
I was having a problem with codesigning my apps, so I deleted all the keys from the keychain. Then I went to Certificate Assistant => Request a certificate from a Certificate Authority (to create CSR for a new certificate).
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Ruby capitalize every word first letter
... @macsplean the &:method syntax in map is a concise way to call a method on each item in the array. You can then call join to turn that array into a string. The * ' ' is an alternative way to call join. You can think of it as multiplying the items in the array together to create a str...