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What is a NullReferenceException, and how do I fix it?
.... This means you either set it to null, or you never set it to anything at all.
Like anything else, null gets passed around. If it is null in method "A", it could be that method "B" passed a null to method "A".
null can have different meanings:
Object variables which are uninitialized and hence poi...
JavaScript dependency management: npm vs. bower vs. volo [closed]
...s the difference between npm and bower is: npm manages JavaScript modules called packages and Bower manages front-end components (i.e. css, html, and JavaScript) called components. npm is also used to install bower. Here is an expansive article on npm and bower (does not cover volo) it goes into ple...
In C#, should I use string.Empty or String.Empty or “” to intitialize a string?
...person - so I suggest you find out what most people on your team like, and all go with that for consistency. Personally I find "" easier to read.
The argument that "" and " " are easily mistaken for each other doesn't really wash with me. Unless you're using a proportional font (and I haven't worke...
Scanner vs. StringTokenizer vs. String.Split
...
They're essentially horses for courses.
Scanner is designed for cases where you need to parse a string, pulling out data of different types. It's very flexible, but arguably doesn't give you the simplest API for simply getting an array of...
How do I update a Linq to SQL dbml file?
...y in the Properties pane of the DBML. This works for simple changes, like allowing nulls on a field.
The DBML designer is not installed by default in Visual Studio 2015, 2017 or 2019. You will have to close VS, start the VS installer and modify your installation. The LINQ to SQL tools is the feat...
Scala how can I count the number of occurrences in a list
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@ohruunuruus this ought to be an answer (vs comment); i would love to enthusiastically upvote, if it were (and select it as the best answer if i were the OP);
– doug
Feb 13 '15 at 4:01
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C++ wait for user input [duplicate]
...gtao No, it doesn't. Please compile an application on Linux/Unix making a call to system("pause") and see for yourself. I am not talking about the system()( function. But the use of "pause" as a command.
– Zimano
Jan 29 '16 at 14:51
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What's the difference between lists and tuples?
.... A list on the other hand could be used to store multiple locations. Naturally one might want to add or remove locations from the list, so it makes sense that lists are mutable. On the other hand it doesn't make sense to add or remove items from an existing location - hence tuples are immutable.
T...
Getting the count of unique values in a column in bash
... count the frequency of occurrence of the different values in a column for all the files in a folder and sort them in decreasing order of count (highest count first). How would I accomplish this in a Linux command line environment?
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What is the use of static variable in C#? When to use it? Why can't I declare the static variable in
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A static variable shares the value of it among all instances of the class.
Example without declaring it static:
public class Variable
{
public int i = 5;
public void test()
{
i = i + 5;
Console.WriteLine(i);
}
}
public class Exercise
{
...