Which is determined by both the declared accessibility of the member and the accessibility domain of the immediately containing type ，该域是由已声明的成员可访问性和直接包含类型的可访问域这二者共同确定的。
The accessibility domain of a nested type is at least the program text of the type in which it is declared . that is , the type body , including any nested types 嵌套类型的可访问域至少是声明它的类型的程序文本，即包括任何嵌套类型的类型体。
The accessibility of a nested type depends on its accessibility domain , which is determined by both the declared accessibility of the member and the accessibility domain of the immediately containing type 嵌套类型的可访问性依赖于它的可访问域，该域是由已声明的成员可访问性和直接包含类型的可访问域这二者共同确定的。
