c# - 需要参数 '@ID' ，但未提供？

Question

我将 ID 作为外参数发送，但它给出了错误

System.Data.SqlClient.SqlException: Procedure or function 'usp_ClientHistoryItem' expects parameter '@ID', which was not supplied.

代码

 using (SqlCommand cmd = new SqlCommand("dbo.usp_ClientHistoryItem", conn))
 {
      SqlParameter parameterID = new SqlParameter("@ID", oReservation.Id);
      parameterID.Direction = ParameterDirection.Output;
      cmd.Parameters.Add(parameterID); 

      cmd.Parameters.Add(new SqlParameter("@PhoneNo", oReservation.ClientPhone));
      cmd.Parameters.Add(new SqlParameter("@UserId", oReservation.UserID));
      cmd.Parameters.Add(new SqlParameter("@Description", oReservation.Description));
      cmd.Parameters.Add(new SqlParameter("@TestId", oReservation.TestId));
      cmd.Parameters.Add(new SqlParameter("@StartDate", oReservation.StartDate));

      cmd.ExecuteNonQuery();

      returnValue = Convert.ToInt32(cmd.Parameters["@ID"].Value);

      return returnValue;
}

Answer 1

您似乎在调用存储过程 - 但您从未将 SqlCommand定义为存储过程:

using (SqlCommand cmd = new SqlCommand("dbo.usp_ClientHistoryItem", conn))
{
    cmd.CommandType = CommandType.StoredProcedure;  // add this line to tell ADO.NET it's a stored procedure!!

如果您忘记了该行，那么 ADO.NET 将尝试将您的内容解释为临时 SQL 语句....