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FirstOrDefault: Default value other than null
...; set;}
}
void Main()
{
var list = new List<Foo>();
//before C# 6.0
string barCSharp5 = list.DefaultIfEmpty(new Foo()).FirstOrDefault().Bar;
//C# 6.0 or later
var barCSharp6 = list.FirstOrDefault()?.Bar;
}
For C# 6.0 or later:
Use ?. or ?[ to test if is null before perfo...
Java Interfaces/Implementation naming convention [duplicate]
...IService and Service for a single implementation which is really common in c# stackoverflow.com/questions/681700/interface-naming-convention
– amdev
Jan 21 '19 at 21:11
...
List passed by ref - help me explain this behaviour
...ect created on heap. The variable myList is a
reference to that object.
In C# you never pass objects, you pass their references by value.
When you access the list object via the passed reference in
ChangeList (while sorting, for example) the original list is changed.
The assignment on the ChangeList...
Do zombies exist … in .NET?
...tead, or putting the release in a finally block.
See also
Subtleties of C# IL
codegen
for a very subtle case where an exception can prevent a lock from
being released even when using the lock keyword (but only in .Net 3.5 and earlier)
Locks and exceptions do not
mix
...
Are there strongly-typed collections in Objective-C?
I'm new to Mac/iPhone programming and Objective-C. In C# and Java we have "generics", collection classes whose members can only be of the type declared. For example, in C#
...
Is there a way of making strings file-path safe in c#?
...
The C# version: foreach (var c in Path.GetInvalidFileNameChars()) { fileName=fileName.Replace(c, '-'); }
– jcollum
Feb 15 '10 at 22:12
...
How can I take more control in ASP.NET?
...est to a few Stack Overflow'rs if I ever get it done. I'm hosting it on my C# in Depth site, which is vanilla ASP.NET 3.5 (i.e. not MVC).
...
How does having a dynamic variable affect performance?
I have a question about the performance of dynamic in C#. I've read dynamic makes the compiler run again, but what does it do?
...
How To: Execute command line in C#, get STD OUT results
How do I execute a command-line program from C# and get back the STD OUT results? Specifically, I want to execute DIFF on two files that are programmatically selected and write the results to a text box.
...
Joins are for lazy people?
...s less efficient than making several requests and link tables in the code (C# or Java).
21 Answers
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