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How do you cast a List of supertypes to a List of subtypes?
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Simply casting to List<TestB> almost works; but it doesn't work because you can't cast a generic type of one parameter to another. However, you can cast through an intermediate wildcard type and it will be allowed (since you c...
Unable to Cast from Parent Class to Child Class
I am trying to cast from a parent class to a child class but I get an InvalidCastException. The child class only has one property of type int. Does anyone know what I need to do?
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How to get a float result by dividing two integer values using T-SQL?
... you need to use existing fields or parameters which are integers, you can cast them to be floats first:
SELECT CAST(1 AS float) / CAST(3 AS float)
or
SELECT CAST(MyIntField1 AS float) / CAST(MyIntField2 AS float)
shar...
Cast int to varchar
I have below query and need to cast id to varchar
8 Answers
8
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Does Java casting introduce overhead? Why?
Is there any overhead when we cast objects of one type to another? Or the compiler just resolves everything and there is no cost at run time?
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C# “as” cast vs classic cast [duplicate]
I recently learned about a different way to cast. Rather than using
10 Answers
10
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How do I remove code duplication between similar const and non-const member functions?
...amp; get() const {
return c;
}
char & get() {
return const_cast<char &>(static_cast<const C &>(*this).get());
}
char c;
};
The two casts and function call may be ugly but it's correct. Meyers has a thorough explanation why.
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Integer division: How do you produce a double?
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double num = 5;
That avoids a cast. But you'll find that the cast conversions are well-defined. You don't have to guess, just check the JLS. int to double is a widening conversion. From §5.1.2:
Widening primitive conversions do not
lose informa...
How can I reliably get an object's address when operator& is overloaded?
...f_impl
{
static inline T * f( T & v, long ) {
return reinterpret_cast<T*>(
&const_cast<char&>(reinterpret_cast<const volatile char &>(v)));
}
static inline T * f( T * v, int ) { return v; }
};
template<class T>
T * addressof( T & v ) {
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'is' versus try cast with null check
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Because there's only one cast. Compare this:
if (myObj.myProp is MyType) // cast #1
{
var myObjRef = (MyType)myObj.myProp; // needs to be cast a second time
// before using it as a MyType
...
}
to t...