Question

我使用Exp-Func创建了两个选择器我想在一个查询中执行它们。代码如下：

Expression<Func<Scholar, ScholarCultureWatchListView>> selector = z => new ScholarCultureWatchListView
{
    ScholarId = z.ID,
    Name = z.FirstName + " " + z.LastName                                               
};

Expression<Func<Scholar, ScholarCultureWatchListView>> selector2 = z => new ScholarCultureWatchListView
{
    Grade = z.CurrentGrade
};
var result= from s in db.Scholars
            select new ScholarCultureWatchListView
                {
            **?????What is write here (selector, selector2)**
                }



public class ScholarCultureWatchListView
{
    public long ScholarId { get; set; }
    public string Name { get; set; }
    public Grade? Grade { get; set; }
    public bool? HoldOverSkip { get; set; }
    public Grade? GradeHoldOver { get; set; }
    public bool? Iep { get; set; }
    public int Tardies { get; set; }
    public int Absences { get; set; }
    public int YtdSuspensions { get; set; }
    ....
}

请解决我的问题。感谢

Answer 1

如果你想从一次调用中获得两个单独的ScholarCultureWatchListView实例，你可以这样做（你根本不需要选择器）：

var result = from s in db.Scholars
             select new[]
             {
                 new ScholarCultureWatchListView
                 {
                     ScholarId = s.ID,
                     Name = s.FirstName + " " + z.LastName
                 },
                 new ScholarCultureWatchListView
                 {
                     Grade = z.CurrentGrade
                 },
             };

选择器中的表达式功能

1 个答案: