在存储过程中传递表值参数时，对象类型system.collections.generic.list中存在无映射的解决方案 [英] Solution for no mapping exists from object type system.collections.generic.list while passing table valued parameter in store procedure

问题描述

这是两个类文件

These are two class files

public class Salary
{
    .
    .
    .
    public List<TripAllowanceDT> tripAllowancedt { get; set; }

}


public class TripAllowanceDT
{
    public int id { get; set; }
    public string BookingNumber { get; set; }
    public int NewBookingId { get; set; }
    public string TripAllowance { get; set; }
    public DateTime MultidayFromDate { get; set; }
    public int EmployeeId { get; set; }
}

这是调用存储过程的代码

This is the code for calling a stored procedure

  SqlConnection conn = new SqlConnection();
              conn.ConnectionString = ConfigurationManager.ConnectionStrings["DBConnect"].ConnectionString;
              conn.Open();
              SqlCommand sc = new SqlCommand("SP", conn);

sc.Parameters.AddWithValue("AllowanceDT", EmployeeSalary.tripAllowancedt);
             DataTable dt = new DataTable();
              SqlDataAdapter da = new SqlDataAdapter(sc);
              sc.CommandType = CommandType.StoredProcedure;
              da.Fill(dt);

我的尝试：



我已经尝试过另一种方法，它正在那里工作，我已经调试了代码并检查了数据类型中的值。这一切都很好。

我还从存储过程中删除了表值参数的代码。

我刚刚宣布ie

What I have tried:

I have tried for another method and it is working there, I have debugged the code and check values in it with data type as well. And it's all fine.
I have also removed code for the table-valued parameter from the stored procedure.
I have just declared i.e

@AllowanceDT TableType_UpdateAllowance ReadOnly

推荐答案

您正在尝试将集合作为参数传递;没有这样的支持。

You're trying to pass a "collection" as a parameter; there is no such support.

sc.Parameters.AddWithValue("AllowanceDT", EmployeeSalary.tripAllowancedt);

SqlDbType Enum（System.Data）| Microsoft Docs [ ^ ]

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