将匹配多个批量输入的 LINQ 表达式 [重复]

如何编写匹配多个批量输入的 LINQ 表达式？

这是我的数据库表

Members
Division, Department
1           3
4           9       *
5           1
6           3       *
9           2

我想选择标有 * 的成员

这是我的输入

int[] divisions = new int[2] {4, 6};
int[] department = new int[2] {9, 3};

这是我尝试过的查询

var selectedMembers = members.Where(member => divisions.Contains(member.Division) && department.Contains(member.Department)).ToArray();

这在 EF 中行为不正确。它适用于单个输入但不适用于两个输入（部门和部门） 它应该返回输入中匹配的对 例如：

Member[] selectedMembers = new Member[2] { new Member{Division=4,Department=9}, new Member{Division=6,Department=3}};

EF 不直接支持此类过滤。

一种可能的解决方案是动态构建一个谓词，如下所示：

member => (member.Division == divisions[0] && member.Department == departments[0])
       || (member.Division == divisions[1] && member.Department == departments[1])
       ...
       || (member.Division == divisions[N-1] && member.Department == departments[N-1]);

您可以按照以下方法执行此操作：

var parameter = Expression.Parameter(typeof(Member), "member");
var predicate = Expression.Lambda<Func<Member, bool>>(
    Enumerable.Range(0, divisions.Length)
    .Select(i => new Expression[]
    {
        Expression.Equal(Expression.Property(parameter, "Division"), Expression.Constant(divisions[i])),
        Expression.Equal(Expression.Property(parameter, "Department"), Expression.Constant(departments[i])),
    }
    .Aggregate(Expression.AndAlso))
    .Aggregate(Expression.OrElse),
    parameter);
var query = members.Where(predicate);