缺少参数？即使我诱导了它

Question

我正在尝试使用 INSERT 命令将新用户添加到 SQL 数据库，但是当我运行它时会抛出一个错误，指出它需要 @Username 参数。我给了它这个参数：/

任何想法都出错了，我尝试了大约两个小时来修复，但不知道出了什么问题。

我正在使用 ASP.Net Web 表单和 C# 代码

代码如下：

using System;
using System.Collections.Generic;
using System.Linq;
using System.Web;
using System.Web.UI;
using System.Web.UI.WebControls;

using System.Web.Security;
using System.Data.SqlClient;
using HashLibrary;
using System.Configuration;
using System.Text.RegularExpressions;
using System.Data;

namespace LetsRentAgentZoneB
{
    public partial class UserAdd : System.Web.UI.Page
    {
        protected void Page_Load(object sender, EventArgs e)
        {

        }

        protected void LoginBtn_Click(object sender, EventArgs e)
        {
            ResultLbl.Text = Hasher.HashString(PasswordTxt.Text.Trim());
            if (UsernameTxt.Text.Length <= 50 && PasswordTxt.Text.Length <= 25)
            {
                SqlConnection conn = null;

                try
                {
                    conn = new SqlConnection(ConfigurationManager.ConnectionStrings["LetsRent"].ConnectionString);
                    SqlCommand cmd = new SqlCommand("AgentRegisterNewUser", conn);

                    //SqlParameter user = new SqlParameter();
                    //user.ParameterName = "@username";
                    //user.Value = UsernameTxt.Text.Trim();
                    //cmd.Parameters.Add(user);
                    cmd.Parameters.Add("@Username", SqlDbType.VarChar).Value = UsernameTxt.Text.Trim();


                    SqlParameter pass = new SqlParameter();
                    pass.ParameterName = "@password";
                    pass.Value = Hasher.HashString(PasswordTxt.Text.Trim());
                    cmd.Parameters.Add(pass);

                    try
                    {
                        conn.Open();
                        cmd.ExecuteNonQuery();
                        conn.Close();
                        ResultLbl.Text = "User added!";
                    }
                    catch (Exception ex)
                    {
                        ResultLbl.Text = "error";
                        throw new Exception("Execption adding account. " + ex.Message);
                    }
                }
                catch (Exception ex)
                {
                    ResultLbl.Text = "error";
                    throw new Exception("Execption adding account. " + ex.Message);
                }
            }
          }
    }
}

SQL 命令

USE [LetsRent]
GO
/****** Object:  StoredProcedure [dbo].[AgentRegisterNewUser]    Script Date: 08/04/2014 14:03:51 ******/
SET ANSI_NULLS ON
GO
SET QUOTED_IDENTIFIER ON
GO
-- =============================================
-- Author:      Chris
-- Create date: 08/04/2014
-- Description: Adds a new user to AgentUser Database
-- =============================================
ALTER PROCEDURE [dbo].[AgentRegisterNewUser] 
    -- Add the parameters for the stored procedure here
    @Username VarChar(50), 
    @Password VarChar(25) 
AS
BEGIN
    -- SET NOCOUNT ON added to prevent extra result sets from
    -- interfering with SELECT statements.
    SET NOCOUNT ON;

    -- Insert statements for procedure here
    SELECT @Username, @Password

    INSERT INTO AgentUsers(Username, Password)
    VALUES ( @Username, @Password);
END

Answer 1

我猜AgentRegisterNewUser 是一个存储过程，因此cmd.CommandType 应该是StoredProcedure：

SqlCommand cmd = new SqlCommand("AgentRegisterNewUser", conn);
cmd.CommandType = CommandType.StoredProcedure;

没有此更改，您正在执行由文本“AgentRegisterNewUser”组成的 T-SQL 批处理。这将编译为调用过程，即使没有 exec，但不会传递任何参数，因为您的参数已传递给 batch。