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ReadOnlyCollection or IEnumerable for exposing member collections?
...If you're using .NET 3.5, you can avoid making a copy and avoid the simple cast by using a simple call to Skip:
public IEnumerable<Foo> Foos {
get { return foos.Skip(0); }
}
(There are plenty of other options for wrapping trivially - the nice thing about Skip over Select/Where is that t...
Convert Decimal to Double
...
An explicit cast to double like this isn't necessary:
double trans = (double) trackBar1.Value / 5000.0;
Identifying the constant as 5000.0 (or as 5000d) is sufficient:
double trans = trackBar1.Value / 5000.0;
double trans = trackBar1...
Enum “Inheritance”
... int values to the constants as defined in the existing enum, then you can cast between the enum and the constants, e.g:
public enum SomeEnum // this is the existing enum (from WSDL)
{
A = 1,
B = 2,
...
}
public class Base
{
public const int A = (int)SomeEnum.A;
//...
}
public c...
How to create id with AUTO_INCREMENT on Oracle?
...r replace trigger FOO_trg
before insert on FOO
for each row
begin
select cast(sys_guid() as varchar2(32)) into :new.x from dual; -- string version
-- select sys_guid() into :new.x from dual; -- raw version
end;
/
update:
Oracle 12c introduces these two variants that don't...
What is null in Java?
...e value of the RelationalExpression is not null and the reference could be cast to the ReferenceType without raising a ClassCastException. Otherwise the result is false.
This means that for any type E and R, for any E o, where o == null, o instanceof R is always false.
What set does 'null' b...
Random float number generation
...
This will generate a number from 0.0 to 1.0, inclusive.
float r = static_cast <float> (rand()) / static_cast <float> (RAND_MAX);
This will generate a number from 0.0 to some arbitrary float, X:
float r2 = static_cast <float> (rand()) / (static_cast <float> (RAND_MAX/X));...
constant pointer vs pointer on a constant value [duplicate]
...is constant and immutable but the pointed data is not.
You could use const_cast(in C++) or c-style cast to cast away the constness in this case as data itself is not constant.
const char * a;
means that the pointed data cannot be written to using the pointer a.
Using a const_cast(C++) or c-style ...
How to get current timestamp in milliseconds since 1970 just the way Java gets
...hrono>
// ...
using namespace std::chrono;
milliseconds ms = duration_cast< milliseconds >(
system_clock::now().time_since_epoch()
);
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Does MS SQL Server's “between” include the range boundaries?
... When using BETWEEN to filter DateTimes between two dates, you can also cast the DateTime to a Date, eg: where CONVERT(DATE, MyDate) BETWEEN '2017-09-01' and '2017-09-30' This approach makes the time element of the DateTime irrelevant
– Pete
Sep 15 '17 at 9...
Comparing two byte arrays in .NET
...ner ! The previous solution was slightly more efficient since it saved the cast to IStructuralEquatable (an array is statically known to be IStructuralEquatable), but indeed your suggestions makes the method work for null arguments as well.
– Ohad Schneider
Mar...