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The cast to value type 'Int32' failed because the materialized value is null
... case, where there might be no elements and sql's SUM returns null whereas c# expect 0.
A more general approach is to use ?? which will be translated to COALESCE whenever there is a risk that the generated SQL returns an unexpected null:
var creditsSum = (from u in context.User
join ...
Convert System.Drawing.Color to RGB and Hex Value
Using C# I was trying to develop the following two. The way I am doing it may have some problem and need your kind advice. In addition, I dont know whether there is any existing method to do the same.
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JavaScriptSerializer - JSON serialization of enum as string
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Add the below to your global.asax for JSON serialization of c# enum as string
HttpConfiguration config = GlobalConfiguration.Configuration;
config.Formatters.JsonFormatter.SerializerSettings.Formatting =
Newtonsoft.Json.Formatting.Indented;
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How to play a sound in C#, .NET
I have a Windows application written in C#/.NET.
7 Answers
7
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Nullable type as a generic parameter possible?
...rk at all with reference types (e.g. GetValueOrNull<string>) because C# doesn't seem to like Nullable<(ref type)> like "string?". Robert C Barth & James Jones's solutions, below, seem much better to me if that's your need.
– bacar
Jul 28 '11 at ...
Are getters and setters poor design? Contradictory advice seen [duplicate]
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what about in a language like c# or actionscript, where get and set are part of syntax? isAlive could just have a getter but not a setter.
– Iain
Jul 7 '09 at 11:07
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Max or Default?
...yField = value _
Select CType(y.MyCounter, Integer?)).Max
Or in C#:
var x = (from y in context.MyTable
where y.MyField == value
select (int?)y.MyCounter).Max();
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How to check if IEnumerable is null or empty?
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@Mormegil Why? extension methods finally give C# some capability to work with nulls, which other languages (like Ruby) completely take for granted.
– Matt Greer
Feb 18 '11 at 22:54
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Visual Studio 2013 IntelliSense stops working for ASP.NET MVC5 Controllers
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Tools > Options > Text Editor > C# > General
Make sure that "Auto List Members" is checked
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How to add extension methods to Enums
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Enums in C# kind of suck because this compiles and runs: Duration d = 0;
– Graham
Mar 30 '16 at 15:32
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