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C# 'is' operator performance
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Using is can hurt performance if, once you check the type, you cast to that type. is actually casts the object to the type you are checking so any subsequent casting is redundant.
If you are going to cast anyway, here is a better approach:
ISpecialType t = obj as ISpecialType;
if (t ...
Converting a double to an int in C#
... that is, 4.5 is converted to 4, and 5.5 is converted to 6.
...while the cast truncates:
When you convert from a double or float value to an integral type, the
value is truncated.
Update: See Jeppe Stig Nielsen's comment below for additional differences (which however do not come into play...
Can anonymous class implement interface?
...members such as methods or events are allowed. An anonymous type cannot be cast to any interface or type except for object.
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Undefined reference to static class member
...question. The second part is much more interesting: Why does adding a NOP cast make it work without requiring the external declaration?
– Brent Bradburn
Feb 1 '11 at 0:48
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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
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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...
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
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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 ...