Linq表达式子级实体的n级别

Question

需要以下查询的通用表达式。

I don't want to use the Dynamic library and Predicate builder.

我正在动态生成表达式。

var test = entity.User.Where(PUser => PUser.Role.TeamRoles.Any(PTeamRoles => PTeamRoles.TeamId == "222")));

我想生成一对一的动态表达式，然后是很多关系查询。

Answer 1

我得到了解决方案

Expression proeprtyexpression = Expression.Property（PTeamRoles，“TeamId”）;             表达式valueexpress = Expression.Constant（“A”）;             //表达式innerexpression = Expression.Lambda（Expression.Equal（proeprtyexpression，valueexpress），PTeamRoles）;             表达式innerexpression = Expression.Lambda（ExcelExpressionHelper.ApplyOperator（proeprtyexpression，valueexpress，“StartsWith”），PTeamRoles）;

        Type winnertype = PTeamRoles.Type;
        Type woutertype = PRole.Type;
        var wouterProperty = Expression.Property(PRole, "TeamRoles");

        var outerMethodExpression = Expression.Call(typeof(Enumerable), "Any", new[] { winnertype }, wouterProperty, innerexpression);