C# 0 The Complete Reference

MyClass

, and that 

MyClass

 defines a parameterless 

constructor. Thus, it is valid for use as a type argument for 

Test

. It must be emphasized that 

it was not necessary for 

MyClass

 to explicitly declare a parameterless constructor. Its default 

constructor would also satisfy the constraint. However, if a class needs other constructors 

in addition to a parameterless one, then it would be necessary to also explicitly declare a 

parameterless version, too.

There are three important points about using 

new( )

. First, it can be used with other 

constraints, but it must be the last constraint in the list. Second, 

new( )

 allows you to 

construct an object using only the parameterless constructor, even when other constructors 

are available. In other words, it is not permissible to pass arguments to the constructor of a 

type parameter. Third, you cannot use 

new( )

 in conjunction with a value type constraint, 

described next.