C# ADO.NET Access 为啥更 新不了表，帮帮忙，在线等

[xtgopl]

大哥大姐，帮帮忙，后天教作业呢，还有两层没做了，卡在这里了，谢谢 ^_^

        /// <summary>
        /// 根据学员ＩＤ更新学员信息
        /// </summary>
        /// <param name="student">学员实体</param>
        /// <returns>更新数目</returns>
        public int UpdateStudentInfoByID(Student student)
        {
            int amount = -1;

            if ( student.ID == 0 || student.Name == string.Empty )
                return amount;

            try
            {
                OleDbCommand command = new OleDbCommand();

                command.CommandType = CommandType.Text;
                command.Connection = DBAssistant.Connection;
                command.Parameters.Add("@id", OleDbType.BigInt).Value = student.ID;
                command.Parameters.Add("@name", OleDbType.VarChar, 50).Value = student.Name;
                command.Parameters.Add("@sex", OleDbType.Boolean).Value = student.Sex == Genders.Male ? true : false;
                command.Parameters.Add("@birthday", OleDbType.DBDate).Value = student.Birthday;
                command.Parameters.Add("@mobile", OleDbType.VarChar, 20).Value = student.Mobile;
                command.Parameters.Add("@address", OleDbType.VarChar, 50).Value = student.Address;
                command.CommandText =
                    "UPDATE StuInfo SET "
                    + "SName = @name, Sex = @sex, Birthday = @birthday, Mobile = @mobile, Address = @address "
                    + "WHERE ID = @id;";

                DBAssistant.OpenTheConnection(); // 打开
                amount = command.ExecuteNonQuery(); // 这里一直是 返回 0 ，数据库里也不变化
            }
            catch ( Exception exp )
            {
                Console.WriteLine( exp.Message );
                throw;
            }
            finally
            {
                DBAssistant.ShutTheConnection();
            }

            return amount;
        } // end method UpdateStudentInfoByID

    internal class DALTest
    {
        static void Main(string [] args)
        {
            Access.StudentService accStuService = new Access.StudentService(); // 数据层

            // 学生对象，参数为：“姓名”、“性别”
            Models.Student accModify = new School.Models.Student("更新更新更新", Models.Genders.Male);

            accModify.ID = 1; // 学生 ID

            accModify.Mobile = "3683297"; // 电话

            int accAmount = accStuService.UpdateStudentInfoByID(accModify); // 调用更新方法

            Console.WriteLine( accAmount.ToString() ); // 返回受影响的行数 （一直是 0 ）为什么更新不了

[qkqlqq0288]

检查一下你的表，是否设置关键字段，如果没有就不能更新和修改

[SunnyBoy]

最近也在学数据库，关注！

[xtgopl]

//这个一定要调到最后，因为你在SQL中最后一个用到
                command.Parameters.Add("@id", OleDbType.BigInt).Value = student.ID;

sdfkfkd : 谢谢，问题解决了，就是这里！！

[特别]

[Quote=引用楼主 xtgopl 的回复:]
command.Parameters.Add("@id", OleDbType.BigInt).Value = student.ID;
command.Parameters.Add("@name", OleDbType.VarChar, 50).Value = student.Name;
command.Parameters.Add("@sex", OleDbType.Boolean).Value = student.Sex == Genders.Male ? true : false;
command.Parameters.Add("@birthday", OleDbType.DBDate).Value = student.Birthday;
command.Parameters.Add("@mobile", OleDbType.VarChar, 20).Value = student.Mobile;
command.Parameters.Add("@address", OleDbType.VarChar, 50).Value = student.Address;
command.CommandText =
"UPDATE StuInfo SET "
+ "SName = @name, Sex = @sex, Birthday = @birthday, Mobile = @mobile, Address = @address "
+ "WHERE ID = @id;";
[/Quote]
Access数据库的参数不是用参数名来匹配的
而是用问号(?)，必须注意顺序，第一个问号匹配你给出的第一个参数
这些代码要改成

                
                command.Parameters.Add("@name", OleDbType.VarChar, 50).Value = student.Name;
                command.Parameters.Add("@sex", OleDbType.Boolean).Value = student.Sex == Genders.Male ? true : false;
                command.Parameters.Add("@birthday", OleDbType.DBDate).Value = student.Birthday;
                command.Parameters.Add("@mobile", OleDbType.VarChar, 20).Value = student.Mobile;
                command.Parameters.Add("@address", OleDbType.VarChar, 50).Value = student.Address;
                //这个一定要调到最后，因为你在SQL中最后一个用到
                command.Parameters.Add("@id", OleDbType.BigInt).Value = student.ID;
                command.CommandText =
                    "UPDATE StuInfo SET "
                    + "SName = ?, Sex = ?, Birthday =?, Mobile = ?, Address = ? "
                    + "WHERE ID = ?;";

如果不行，将command.Parameters中的参数名也换成？试试