Question

在给定的代码中，我编写了lambda表达式，但它显示了一个错误 - 无法将lambda表达式转换为类型'string'，因为它不是委托类型。

        EmployeeDataOperation emp = new EmployeeDataOperation(); //Class to perform CRUD operation.

        List<EmployeeProp> data = new List<EmployeeProp>();

        dt = emp.getEmployeeData();//return datatable with records.

        //I want to use lambda expression to use Datatable data as a list
        data = (from a in dt
                select new EmployeeProp { Name = a.Name, Email = a.Email }).ToList();
        //error near select

        return View(data);

Answer 1

您可以使用.Field linq扩展名或索引/列名称（前行[“columnname”]来访问DataRow中的值。我建议使用Field扩展名，因为它甚至可以处理nullable种类型。

data  = dt.AsEnumerable()
  .Select(row=>  new EmployeeProp ()
   {
       Name = row.Field<string>("Name"),
       Email = row.Field<string>("Email ") 
       // Other properties....      
   })
   .ToList();

Answer 2

 var myData = (from a in dt.AsEnumerable()
               select new EmployeeProp { 
                   Name = a.Field<string>("Name"), 
                   Email = a.Field<string>("Email") 
              }).ToList();

Answer 3

您也可以尝试这样做，制作EmployeeProp（）对象

data = (from a in dt
                select new EmployeeProp() { Name = a.Name, Email = a.Email }).ToList();

如何使用lambda表达式将DataTable记录放入列表中？

3 个答案: