Stored procedures ASP.NET MVC中带有存储过程的ExecuteOnQuery处缺少参数

下面是我的代码，我在

ExecuteNonQuery

上得到一个错误：

@缺少名称参数

我已经尝试了很多次，甚至在建立程序的过程中没有错误。存储过程包含一个带有4个参数的insert语句，其中3个为

varchar

类型，一个为

integer

类型，作为主键

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Configuration;
using System.Data;
using System.Data.SqlClient;

namespace CompanyMaster
{
    public class Master
    {
         public IEnumerable<Company> Companies
         {
            get
            {
                string connectionString = ConfigurationManager.ConnectionStrings["DBCS"].ConnectionString;

                List<Company> companies = new List<Company>();

                using (SqlConnection con = new SqlConnection(connectionString))
                {
                    SqlCommand cmd = new SqlCommand("spGetAllCompany", con);
                    cmd.CommandType = CommandType.StoredProcedure;
                    con.Open();

                    SqlDataReader rdr = cmd.ExecuteReader();

                    while (rdr.Read())
                    {
                        Company company = new Company();
                        company.CompanyCode = Convert.ToInt32(rdr["CompanyCode"]);
                        company.CompanyName = rdr["CompanyName"].ToString();
                        company.CompanyAddress = rdr["CompanyAddress"].ToString();
                        company.CompanyMail = rdr["CompanyMail"].ToString();

                        companies.Add(company);
                    }
                }
                return companies;
            }
       }

       public void Addcompany(Company company)
       {    
           string connectionString = ConfigurationManager.ConnectionStrings["DBCS"].ConnectionString;

           using (SqlConnection con = new SqlConnection(connectionString))
           {
               SqlCommand cmd = new SqlCommand("spAddCompany", con);
               cmd.CommandType = CommandType.StoredProcedure;

               cmd.Parameters.Clear();

               SqlParameter paramCode = new SqlParameter();
               paramCode.ParameterName = "@Code";
               paramCode.Value = company.CompanyCode;
               cmd.Parameters.Add(paramCode);

               SqlParameter PName = new SqlParameter("@Name", SqlDbType.VarChar, 50);
               //PName.ParameterName = "@Name";
               PName.Value = company.CompanyName;
               cmd.Parameters.Add(PName);

               SqlParameter paramAddress = new SqlParameter();
               paramAddress.ParameterName = "@Address";
               paramAddress.Value = company.CompanyAddress;
               cmd.Parameters.Add(paramAddress);

               SqlParameter paramMail = new SqlParameter();
               paramMail.ParameterName = "@Mail";
               paramMail.Value = company.CompanyMail;
               cmd.Parameters.Add(paramMail);

               con.Open();
               cmd.ExecuteNonQuery();-- error is occurring here
           }
       }
    }
}

---

@Name

参数在代码到达

ExecuteNonQuery

时丢失，我认为您的问题与

null

vs

DBNull.Value

检查

company.CompanyName

是否为空（在c#中）。如果是，则应改为传递

DBNull.Value

。
有关两者区别的更多信息，请阅读

发件人：

注意

向服务器发送空参数值时，必须指定，而不是

null

（

Nothing

，在Visual Basic中）。系统中的

null

值是没有值的空对象。用于表示空值。有关数据库空值的详细信息，请参见

此外，还可以向命令中添加参数，并在一行代码中设置其值，如下所示：

cmd.Parameters.Add("@Name", SqlDbType.NVarChar, 50).Value = company.CompanyName;

这将使您的代码更短，可读性更强

以下是我对您的代码所做的更改，我认为这些更改可以解决您的问题：

public void Addcompany(Company company)
{    
    string connectionString = ConfigurationManager.ConnectionStrings["DBCS"].ConnectionString;

    using (var con = new SqlConnection(connectionString))
    {
        // SqlCommand also implements the IDisposable interface
        using(var cmd = new SqlCommand("spAddCompany", con))
        {
            cmd.CommandType = CommandType.StoredProcedure;
            cmd.Parameters.Add("@Code",  SqlDbType.Int).Value = company.CompanyCode;
            cmd.Parameters.Add("@Name", SqlDbType.VarChar, 50).Value = company.CompanyName as object ?? (object)DBNull.Value;
            cmd.Parameters.Add("@Address", SqlDbType.VarChar, 50).Value = company.CompanyAddress as object ?? (object)DBNull.Value;
            cmd.Parameters.Add("@Mail", SqlDbType.VarChar, 50).Value = company.CompanyMail as object ?? (object)DBNull.Value;
            con.Open();
            cmd.ExecuteNonQuery();
        }
    }
}

---

注意空合并操作符（

？？

）的使用和对

对象的转换
侧注：存储过程中
@Name
参数的类型是
NVARCHAR
，但在C代码中是
SqlDbType.VarChar
。您应该将其更改为
SqlDbType.NVarChar
。所有其他参数也应该使用相同的样式。不起作用..谢谢这只是旁注，不是解决方案。@RacilHilan ok。。
public void Addcompany(Company company)
{    
    string connectionString = ConfigurationManager.ConnectionStrings["DBCS"].ConnectionString;

    using (var con = new SqlConnection(connectionString))
    {
        // SqlCommand also implements the IDisposable interface
        using(var cmd = new SqlCommand("spAddCompany", con))
        {
            cmd.CommandType = CommandType.StoredProcedure;
            cmd.Parameters.Add("@Code",  SqlDbType.Int).Value = company.CompanyCode;
            cmd.Parameters.Add("@Name", SqlDbType.VarChar, 50).Value = company.CompanyName as object ?? (object)DBNull.Value;
            cmd.Parameters.Add("@Address", SqlDbType.VarChar, 50).Value = company.CompanyAddress as object ?? (object)DBNull.Value;
            cmd.Parameters.Add("@Mail", SqlDbType.VarChar, 50).Value = company.CompanyMail as object ?? (object)DBNull.Value;
            con.Open();
            cmd.ExecuteNonQuery();
        }
    }
}