问题
in some project we are using Generics, and we get a lot of lines like this:
Line<SomeTClass,SomeCClass> myLine =
(Line<SomeTClass,SomeCClass>)LineFactory.CreateLine(...)
We can declare local alias, with using X = Line<SomeTClass,SomeCClass>
.
Then we can write, X myLine = (X)LineFactory.CreateLine(...)
.
We have a lot a combination of <T,C>
but we often use the same. Is it possible de declare the using globally, so that we won't have to declare the alias in each file?
回答1:
No such thing as a global alias. What you can do is use type inference to simplify your declarations:
var myLine = (Line<SomeTClass, SomeCClass>)LineFactory.CreateLine(...);
and if that's not specific enough for the inference system, you can make the CreateLine() method generic to enforce it:
var myLine = LineFactory.CreateLine<Line<SomeTClass, SomeCClass>>(...);
and given the name of the LineFactory type, maybe even simplify it some more:
var myLine = LineFactory.CreateLine<SomeTClass, SomeCClass>(...);
This last option feels "right" to me in some way I can't fully articulate. Just in case you need a little help, the method declaration would look like something this:
public static class LineFactory
{
public static Line<T,C> CreateLine<T,C>(...) { ... }
}
回答2:
No, you cannot create a global alias.
来源:https://stackoverflow.com/questions/7577692/c-globally-alias-a-generic-class-name