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The cast to value type 'Int32' failed because the materialized value is null
...
where u.ID == userID
select (int?)ch.Amount).Sum() ?? 0;
This first casts to int? to tell the C# compiler that this expression can indeed return null, even though Sum() returns an int. Then we use the normal ?? operator to handle the null case....
Inspect hovered element in Chrome?
...er over the element to bring up the tooltip, right click as if you were to select 'Inspect Element'. Leaving that context menu open, move the focus over to the dev tools. The html for the tooltip should show up next to the element its a tooltip for in the HTML. Then you can look at it as if it were ...
Loaded nib but the 'view' outlet was not set
...is is Josh Justice proposal, but in a graphical way (pictures are mine):
Select File owner
On right hand side panel select custom class.
Enter the custom class name
On right hand side panel select oultets
Drag view outlet to view component
Finally the View Controller is instantiated with ...
Exclude folders from Eclipse search
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In Eclipse Kepler there is a "Select a working set type" dialog that comes up after clicking New. (Worth noting that to find all types of file need to select "Resource" at this point.)
– Steve Chambers
Oct 8 '15 at 1...
How to enable NSZombie in Xcode?
...cheme".
To edit the scheme and turn on zombies:
In the "Product" menu, select "Edit Scheme".
Go to the "Run Foo.app" stage in the left panel, and the "Arguments" tab on the right.
Add NSZombieEnabled to the "Environment Variables" section and set the value to YES, as you could in Xcode 3.
In...
How to find children of nodes using BeautifulSoup
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This answers the question how to select <a>link1</a> in the HTML given in the question, but this will FAIL when the first <li class="test"> will contain no <a> elements and there are other li elements with test class that contains<...
MySQL - ORDER BY values within IN()
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SELECT id, name
FROM mytable
WHERE name IN ('B', 'A', 'D', 'E', 'C')
ORDER BY FIELD(name, 'B', 'A', 'D', 'E', 'C')
The FIELD function returns the position of the first string in the remaining list of strings.
However, it i...
Convert form data to JavaScript object with jQuery
... @Marek, I did a test for here on jsfiddle. The trick is to name your select properly. <select name="foo" multiple="multiple"> will not work in any scenario. However, if you use [], as in <select name="bar[]" multiple="multiple">, it will work just fine :)
– ma...
Reject binary with state waiting for review (can't find reject binary button)
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In iTunes connect, from 'My apps', select
Click your application, then
Make sure you are on the 'Versions' tab, and that the correct version is selected.
Click 'Remove this version from review' located in the info bubble.
See below
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intellij - spring is not being recognized (Unmapped Spring configuration)
...alog (either by clicking the warning or through file=>project structure
select the modules item in the left hand list
go through and right click on the modules with missing files and select Add=>Spring
in the new tab click the + button
you should now see a list of the xml files. Check the box...