常量不能用查询表达式进行初始化，因为常量只能用文本、命名常量和数学运算符的某一组合进行初始化。

Constants cannot be initialized with query expressions because constants may only be initialized with some combination of literals, named constants, and mathematical operators.

youdao

LINQ中的集合作业指的是让查询作业根据同一集合或不同集合内是否有对等项目来传回结果集。

Set operations in LINQ refer to query operations that produce a result set that is based on the presence or absence of equivalent elements within the same or separate collections (or sets).

youdao

LINQ中的集合作业指的是让查询作业根据同一集合或不同集合内是否有对等项目来传回结果集。

Set operations in LINQ refer to query operations that produce a result set that is based on the presence or absence of equivalent elements within the same or separate collections (or sets).

youdao