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What does void mean in C, C++, and C#?
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Not disagreeing, but an additional use of void is in the "cast to void" trick to suppress warnings for unused values. It's a bit of a stretch since it doesn't really correspond with how the compiler interprets things, but you can interpret that to mean "I'm using this value to do no...
Is it better to use Enumerable.Empty() as opposed to new List() to initialize an IEnumerable
...y. As for AsEnumerable, it's not really needed but it prevents Roles being cast to IList and modified.
– Lee
Dec 12 '09 at 18:07
add a comment
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How to do ToString for a possibly null object?
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C# 6.0 Edit:
With C# 6.0 we can now have a succinct, cast-free version of the orignal method:
string s = myObj?.ToString() ?? "";
Or even using interpolation:
string s = $"{myObj}";
Original Answer:
string s = (myObj ?? String.Empty).ToString();
or
string s = (myObjc ?? "")....
SQL query for today's date minus two months
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SELECT COUNT(1)
FROM FB
WHERE
Dte BETWEEN CAST(YEAR(GETDATE()) AS VARCHAR(4)) + '-' + CAST(MONTH(DATEADD(month, -1, GETDATE())) AS VARCHAR(2)) + '-20 00:00:00'
AND CAST(YEAR(GETDATE()) AS VARCHAR(4)) + '-' + CAST(MONTH(GETDATE()) AS VARCHAR(2)) + '-20 00:00:0...
How do I trim leading/trailing whitespace in a standard way?
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You have to cast the argument for isspace to unsigned char, otherwise you invoke undefined behavior.
– Roland Illig
Sep 18 '16 at 1:56
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Difference between numeric, float and decimal in SQL Server
...link:
"I frequently do calculations against decimal values. In some cases casting decimal values to float ASAP, prior to any calculations, yields better accuracy. "
http://sqlblog.com/blogs/alexander_kuznetsov/archive/2008/12/20/for-better-precision-cast-decimals-before-calculations.aspx
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How do I check if a C++ std::string starts with a certain string, and convert a substring to an int?
...dy using Boost, you can do it with boost string algorithms + boost lexical cast:
#include <boost/algorithm/string/predicate.hpp>
#include <boost/lexical_cast.hpp>
try {
if (boost::starts_with(argv[1], "--foo="))
foo_value = boost::lexical_cast<int>(argv[1]+6);
} c...
How to get the caller's method name in the called method?
...ccessing.
import inspect
from types import FrameType
from typing import cast
def caller_name() -> str:
"""Return the calling function's name."""
# Ref: https://stackoverflow.com/a/57712700/
return cast(FrameType, cast(FrameType, inspect.currentframe()).f_back).f_code.co_name
if...
How do I convert an object to an array?
...Single-dimensional arrays
For converting single-dimension arrays, you can cast using (array) or there's get_object_vars, which Benoit mentioned in
his answer.
// Cast to an array
$array = (array) $object;
// get_object_vars
$array = get_object_vars($object);
They work slightly different fro...
How do I check for nulls in an '==' operator overload without infinite recursion?
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Cast to object in the overload method:
public static bool operator ==(Foo foo1, Foo foo2) {
if ((object) foo1 == null) return (object) foo2 == null;
return foo1.Equals(foo2);
}
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