Is there a C# equivalent of VB6's Choose() function?
day = Ch开发者_JAVA百科oose(month,31,28,30)
Not really. You can of course create an array an use its indexed getter:
day = new[] { 31, 28, 30 }[month];
Alternatively, you could - I wouldn't - import the Microsoft.VisualBasic
namespace and do:
day = Interaction.Choose(month, 31, 28, 30);
I do not know how much your example is simplified, but in the case that you are actually looking for a way to find the numbers of days in a specific month, try DateTime.DaysInMonth()
:
day = DateTime.DaysInMonth(2008, 2);
// day == 29
If it is really about the days in a month I would follow the advice others have given. However if you really need a Choose function you can easily build one yourself. For example like this:
public static T Choose<T>(int index, params T[] args)
{
if (index < 1 || index > args.Length)
{
return default(T);
}
else
{
return args[--index];
}
}
// call it like this
var day = Choose<int?>(1, 30, 28, 29); // returns 30
I did not bother to make the first argument a double, but this can easily be done. It is also possible to make a non-generic version...
I will sugest, you use DateTime.DaysInMonth
instead :)
My first guess will be
var days = new[] { 31, 28, 30 }[month];
Although native version does all sorts of crazy stuff, like rounding and kind-of-bounds-checking.
Simple answer: No.
If you are looking to do only what you sample is doing, try DateTime.DaysInMonth(year,month)
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