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Why cast unused return values to void?
...asting an unused return value to void, or am I right in thinking it's a complete waste of time?
9 Answers
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Identify if a string is a number
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int n;
bool isNumeric = int.TryParse("123", out n);
Update As of C# 7:
var isNumeric = int.TryParse("123", out int n);
or if you don't need the number you can discard the out parameter
var isNumeric = int.TryParse("123", out _);
The var s can be re...
How to get current working directory in Java?
...ay I have my main class in C:\Users\Justian\Documents\ . How can I get my program to show that it's in C:\Users\Justian\Documents ?
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ORA-00979 not a group by expression
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You must put all columns of the SELECT in the GROUP BY or use functions on them which compress the results to a single value (like MIN, MAX or SUM).
A simple example to understand why this happens: Imagine you have a database like th...
Distinct by property of class with LINQ [duplicate]
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You can use grouping, and get the first car from each group:
List<Car> distinct =
cars
.GroupBy(car => car.CarCode)
.Select(g => g.First())
.ToList();
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How to prevent IFRAME from redirecting top-level window
...ebsites have code to "break out" of IFRAME enclosures, meaning that if a page A is loaded as an IFRAME inside an parent page P some Javascript in A redirects the outer window to A .
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ERROR 2002 (HY000): Can't connect to local MySQL server through socket '/tmp/mysql.sock'
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It's probably because MySQL is installed but not yet running.
To verify that it's running, open up Activity Monitor and under "All Processes", search and verify you see the process "mysqld".
You can start it by installing "MySQL...
How to check if an object is an array?
I'm trying to write a function that either accepts a list of strings, or a single string. If it's a string, then I want to convert it to an array with just the one item so I can loop over it without fear of an error.
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What is the difference between the 'COPY' and 'ADD' commands in a Dockerfile?
What is the difference between the COPY and ADD commands in a Dockerfile, and when would I use one over the other?
13 A...
How do I check if a directory exists? “is_dir”, “file_exists” or both?
... should check both. There might be a regular file named 'foo', which would prevent you from creating a directory name 'foo'.
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