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Sequence contains more than one element
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The problem is that you are using SingleOrDefault. This method will only succeed when the collections contains exactly 0 or 1 element. I believe you are looking for FirstOrDefault which will succeed no matter how many elements are in the collection.
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How can you determine a point is between two other points on a line segment?
...points (called a and b) on it represented by an x integer and a y integer for each point.
20 Answers
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UIViewController viewDidLoad vs. viewWillAppear: What is the proper division of labor?
... server, you also have to think about latency. If you pack all of your network communication into viewDidLoad or viewWillAppear, they will be executed before the user gets to see the view - possibly resulting a short freeze of your app. It may be good idea to first show the user an unpopulated view ...
ASP.NET MVC Razor pass model to layout
...yout page. The reason I don't like typing the layout page is that it will force you to always inherit a "base" viewmodel in all you specific view models. In my experience this usually isn't a very good idea and a lot of the time you will have issues when it's to late to change the design (or it will...
Convert a String representation of a Dictionary to a dictionary?
... in Python 2.6 you can use the built-in ast.literal_eval:
>>> import ast
>>> ast.literal_eval("{'muffin' : 'lolz', 'foo' : 'kitty'}")
{'muffin': 'lolz', 'foo': 'kitty'}
This is safer than using eval. As its own docs say:
>>> help(ast.literal_eval)
Help on function li...
Unique fields that allow nulls in Django
...ar field should be unique, but allow nulls in it, meaning I want to allow more than one record if bar field is null , but if it is not null the values must be unique.
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How to properly compare two Integers in Java?
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No, == between Integer, Long etc will check for reference equality - i.e.
Integer x = ...;
Integer y = ...;
System.out.println(x == y);
this will check whether x and y refer to the same object rather than equal objects.
So
Integer x = new Integer(10);
Integer y = ...
Validate a username and password against Active Directory?
How can I validate a username and password against Active Directory? I simply want to check if a username and password are correct.
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Is there a software-engineering methodology for functional programming? [closed]
Software Engineering as it is taught today is entirely focused on object-oriented programming and the 'natural' object-oriented view of the world. There is a detailed methodology that describes how to transform a domain model into a class model with several steps and a lot of (UML) artifacts like us...