相关疑难解决方法(0)

所以我试图从我的数据库中获取"客户",但我得到一个例外

System.Data.dll中出现"System.Data.SqlClient.SqlException"类型的异常,但未在用户代码中处理

附加信息:必须声明标量变量"@Id".

    using Core;
    using System;
    using System.Collections.Generic;
    using System.Configuration;
    using System.Data.SqlClient;
    using System.Linq;
    using System.Text;
    using System.Threading.Tasks;

    namespace DatabaseAccess
    {
        public class DbCustomer
        {
            private string ConnectionString = ConfigurationManager.ConnectionStrings["local"].ConnectionString;
            private SqlConnection connection { get; set; }

            public DbCustomer()
            {
                connection = new SqlConnection(ConnectionString);
            }

            public Customer GetCustomer(int Id)
            {
                Customer customer = null;
                connection.Open();

                using (SqlCommand command = connection.CreateCommand())
                {
                    command.CommandText = "SELECT * FROM CUSTOMER WHERE Id = @Id;";
                    var reader = command.ExecuteReader();
                    while (reader.Read()) …