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Difference between Arrays.asList(array) and new ArrayList(Arrays.asList(array))
...other interface. See the wrapper pattern article. | Where do you need to upcast? I'd suggest to use List<Integer> for your variable types (or method arguments etc.). This makes your code more generic and you can easily switch to another List implementation as needed, without having to rewrite ...
How do you create a dropdownlist from an enum in ASP.NET MVC?
...adata);
IEnumerable<TEnum> values = Enum.GetValues(enumType).Cast<TEnum>();
IEnumerable<SelectListItem> items = from value in values
select new SelectListItem
{
Text = GetEnumDescription(value),
Value = value....
What is an example of the Liskov Substitution Principle?
...
A great example illustrating LSP (given by Uncle Bob in a podcast I heard recently) was how sometimes something that sounds right in natural language doesn't quite work in code.
In mathematics, a Square is a Rectangle. Indeed it is a specialization of a rectangle. The "is a" makes you...
How do I check if a type is a subtype OR the type of an object?
...lue);
if (testInstance==null)
throw new InvalidCastException("HelperType must be derived from A");
_helperType = value;
}
}
}
I feel like I might be a bit naive here so any feedback would be welcome.
...
When should I use double instead of decimal?
...ecimal is causing bottlenecks or slow-downs. In those cases, I will "down cast" to double or float, but only do it internally, and carefully try to manage precision loss by limiting the number of significant digits in the mathematical operation being performed.
In general, if your value is transie...
What is a difference between
...ecause you can be sure that whatever the actual list contains, it can be upcasted to a Number (after all anything that extends Number is a Number, right?)
However, you are not allowed to put anything into a covariant structure.
myNumst.add(45L); //compiler error
This would not be allowed, because J...
Should switch statements always contain a default clause?
...akes appropriate action for unhandled values, in case an invalid value was cast to the enum type. So this may work best for simple cases where you can return within the enum case rather than break.
enum SomeEnum
{
ENUM_1,
ENUM_2,
// More ENUM values may be added in future
};
int foo(So...
What is the fastest/most efficient way to find the highest set bit (msb) in an integer in C?
...2_t *)&ff))>>20)-1023; // assumes x86 endianness
This version casts the value to a double, then reads off the exponent, which tells you where the bit was. The fancy shift and subtract is to extract the proper parts from the IEEE value.
It's slightly faster to use floats, but a float ca...
How do I reflect over the members of dynamic object?
...lt;string, object> for its properties, so the solution is as trivial as casting:
IDictionary<string, object> propertyValues = (IDictionary<string, object>)s;
Note that this will not work for general dynamic objects. In these cases you will need to drop down to the DLR via IDynamic...
How to check if an object is a certain type
... type for the TypeName Bar.
In some instances, the type an object has been Cast to is different from the type an object was first instantiated from. In the following example, MyObj is an Integer cast into an Object:
Dim MyVal As Integer = 42
Dim MyObj As Object = CType(MyVal, Object)
So, is MyObj...