Question

我正在尝试使用谓词构建器通过MVC3执行查询。我收到了错误

“无法将类型'System.Boolean'强制转换为'System.Object'.LINQ to Entities仅支持转换实体数据模型基元类型。”

我的查询传递如下

if (!string.IsNullOrEmpty(SearchObj.EmployeeIDSortId.ToString()) && SearchObj.EmployeeIDSortId > 0)
    {

        string[] vals =new string[' ']; 
        if (SearchObj.EmployeeIDSortId == 1)
        {
            vals = new string[] { "a", "b", "c", "d", "e", "f", "g", "h", "i", "j", "k","l" };

        }
        else if (SearchObj.EmployeeIDSortId == 2)
        {

            vals = new string[] { "m", "n", "o", "p", "q", "r", "s" };

        }
        else if (SearchObj.EmployeeIDSortId == 3)
        {


            vals = new string[] { "t", "u", "v", "w", "x", "y", "z" };
        }


        employeepredicate =
            employeepredicate.And(emp => emp.EmployeeName.Substring(0, 1).ToLower().Equals(vals.Any()));


         }

你能告诉我这有什么问题，我想这只是因为我的查询vals.Any（）。

谢谢

Answer 1

我先写一下 - 我不熟悉And方法，但.Equals(vals.Any())看起来不对我。所以，我假设And接受一个返回bool的函数。您真正想要的是找出员工姓名中的第一个字符是否包含在vals数组中：

employeepredicate = employeepredicate.And( emp => vals.Contains(emp.EmployeeName.Substring(0, 1).ToLower()));

谓词构建器包含

1 个答案: