应用SqlHelper例子（userService）

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using OA.Model;
using System.Data.SqlClient;
using System.Data;

namespace OA.Dal
{
    public class userService
    {

        /// <summary>
        /// 判断用户是否存在
        /// </summary>
        /// <param name="loginName">登录名</param>
        /// <returns></returns>
        public bool Exists(string loginName)
        {
            string sql = "select count(*) from users where loginname=@name";
            SqlParameter[] pars ={
                                 new SqlParameter("@name",SqlDbType .VarChar ,50)
                                 };
            pars[0].Value = loginName;

            if ((int)SqlHelper.ExecuteScalar(sql,pars) > 0)
            {
                return true;
            }
            else
            {
                return false;
            }

        }

        /// <summary>
        /// 管理员添加用户的基本信息
        /// </summary>
        /// <param name="model"></param>
        /// <returns></returns>
        public int AddBaseUser(users model)
        {
            StringBuilder strsql = new StringBuilder();
            strsql.Append("insert into users(");
            strsql.Append("deptid,loginname,loginpwd,name)");
            strsql.Append(" values (");
            strsql.Append("@deptid,@loginname,@loginpwd,@name)");

            SqlParameter[] parameters = {
     new SqlParameter("@deptid", SqlDbType.Int,4),
     new SqlParameter("@loginname", SqlDbType.NVarChar,50),
     new SqlParameter("@loginpwd", SqlDbType.NVarChar,50),
     new SqlParameter("@name", SqlDbType.NVarChar,20) };
            parameters[0].Value = model.Deptid;
            parameters[1].Value = model.Loginname;
            parameters[2].Value = model.Loginpwd;
            parameters[3].Value = model.Name;
            int result = SqlHelper.ExecuteNonQuery(strsql.ToString(), parameters);
            return result;
        }
       
        /// <summary>
        /// 删除用户信息
        /// </summary>
        /// <param name="id"></param>
        public int Delete(users model)
  {   
   StringBuilder strSql=new StringBuilder();
   strSql.Append("delete from users ");
   strSql.Append(" where id=@id ");
   SqlParameter[] parameters = {
     new SqlParameter("@id", SqlDbType.Int,4)};
   parameters[0].Value = model.Id;

            int result=SqlHelper .ExecuteNonQuery(strSql.ToString(),parameters);
            return result;
  }

        /// <summary>
        /// 根据登录名id获取部门类型id
        /// </summary>
        /// <param name="id"></param>
        /// <returns></returns>
        public string GetDeptid(int id)
        {
            string sql = "select deptid from users where id=@id";
            SqlParameter[] pars ={
                                    new SqlParameter("@id",SqlDbType.Int,4)
                                    };
            pars[0].Value = id;
            object result = SqlHelper.ExecuteScalar(sql, pars);
            if (result != null)
                return result.ToString();
            return null;
        }

        /// <summary>
        /// 批量删除用户信息
        /// </summary>
        /// <param name="ids"></param>
        /// <returns></returns>
        public int Deletes(string[] ids)
        {
            if (ids.Length == 0)
            {
                return 0;
            }
            else
            {
                int result = 0;
                for (int i = 0; i < ids.Length; i++)
                {
                    string sql = "delete from users where id=@id ";
                    SqlParameter[] pars ={
                                        new SqlParameter("@id",SqlDbType.Int)
                                        };
                    pars[0].Value = ids[i];
                    result = SqlHelper.ExecuteNonQuery(sql, pars);
                    if (result != 1)
                    {
                        return 0;
                    }                  
                }
                return 1;
            }
        }

        /// <summary>
        /// 修改用户信息
        /// </summary>
        /// <param name="model"></param>
        /// <returns></returns>
        public int Update(users model)
        {
            StringBuilder strSql = new StringBuilder();
            strSql.Append("update users set ");
            strSql.Append("deptid=@deptid,");
            strSql.Append("loginname=@loginname,");
            strSql.Append("name=@name,");

            strSql.Append(" where id=@id ");
            SqlParameter[] parameters = {
     new SqlParameter("@id", SqlDbType.Int,4),
     new SqlParameter("@deptid", SqlDbType.Int,4),
                    new SqlParameter("@loginname",SqlDbType.NVarChar,50),
     new SqlParameter("@name", SqlDbType.NVarChar,20)};
            parameters[0].Value = model.Id;
            parameters[1].Value = model.Deptid;
            parameters[2].Value = model.Loginname;
            parameters[3].Value = model.Name;
            int result = SqlHelper.ExecuteNonQuery(strSql.ToString(), parameters);
            return result;
        }

        /// <summary>
        /// 修改用户密码
        /// </summary>
        /// <param name="loginname"></param>
        /// <param name="user"></param>
        /// <returns></returns>
         public int UpdatePwd(string loginname, users user)
        {
            string sql = "update users set loginpwd=@pwd where loginname=@name";
            SqlParameter[] pars ={
                                new SqlParameter("@pwd",SqlDbType.NVarChar,50),
                                new SqlParameter("@name",SqlDbType.NVarChar,50)
                                };
            pars[0].Value = user.Loginpwd;
            pars[1].Value = loginname;

            int result= SqlHelper.ExecuteNonQuery(sql, pars);
            return result;
        }
         /// <summary>
         /// 记住上次登入的时间
         /// </summary>
         /// <param name="muser"></param>
         /// <returns></returns>
         public int GetLastTime(Model.users model)
         {
             StringBuilder sql = new StringBuilder();
             sql.Append("update users set lastlogintime=@time where id=@id");
             SqlParameter[] pars ={
                                new SqlParameter("@time",SqlDbType.DateTime,16),
                                new SqlParameter("@id",SqlDbType.Int,4)
                                };
             pars[0].Value = model.Lastlogintime;
             pars[1].Value = model.Id;

             int result = SqlHelper.ExecuteNonQuery(sql.ToString(), pars);
             return result;

         }
     

        /// <summary>
        /// 获取用户列表
        /// </summary>
        /// <param name="where"></param>
        /// <returns></returns>
        public List<users> getAllUser(string where)
        {
            string sql = "select * from users where 1=1";
            if (where.Length > 0)
            {
                sql += where;
            }
            List<users> list = new List<users>();          
            SqlDataReader dr = SqlHelper.ExecuteReader(sql);
            lock (dr)
            {
                if (dr.HasRows)
                {
                    while (dr.Read())
                    {
                        users model = new users()
                        {
                            Id = dr.GetInt32(0),
                            Deptid =dr[1]==System.DBNull.Value?0: dr.GetInt32(1),
                            Loginname = dr[2] == System.DBNull.Value ? "" : dr.GetString(2),
                            Loginpwd = dr[3] == System.DBNull.Value ? "" : dr.GetString(3),
                            Name =dr[4]==System.DBNull.Value?"": dr.GetString(4)
                            };
                        list.Add(model);
                    }
                    dr.Close();
                }
                dr.Dispose();
                return list;
            }           
        }

        /// <summary>
        /// 分页获取列表
        /// </summary>
        /// <param name="curpage"></param>
        /// <param name="pagecount"></param>
        /// <returns></returns>
        public List<users> getUserByPage(int curpage, int pagecount)
        {
            List<users> list = new List<users>();
            string sql = null;
            SqlParameter[] pars ={
                              new SqlParameter("@curpage",SqlDbType.Int),
                              new SqlParameter("@pagecount",SqlDbType.Int)
                              };
            pars[0].Value = curpage;
            pars[1].Value = pagecount;
            SqlDataReader dr = null;
            users user = null;
            sql = "exec proc_page_user " + curpage + "," + pagecount;
            dr = SqlHelper.ExecuteReader(sql, pars);
            if (dr.HasRows)
            {
                while (dr.Read())
                {
                    user = new users()
                    {
                        Id = dr.GetInt32(0),
                        Deptid = dr[1] == System.DBNull.Value ? 0 : dr.GetInt32(1),
                        Loginname = dr[2] == System.DBNull.Value ? "" : dr.GetString(2),
                        Loginpwd = dr[3] == System.DBNull.Value ? "" : dr.GetString(3),
                        Name = dr[4] == System.DBNull.Value ? "" : dr.GetString(4)                       
                    };
                    list.Add(user);
                }
                dr.Close();               
            }
            dr.Dispose();
            return list;
        }

        /// <summary>
        /// 传值
        /// </summary>
        /// <param name="id"></param>
        /// <returns></returns>
        public string GetNameById(int id)
        {
            string sql = "select [name] from users where id=@id";
            SqlParameter[] pars ={
                                    new SqlParameter("@id",SqlDbType.Int,4)
                                    };
            pars[0].Value = id;
            object result = SqlHelper.ExecuteScalar(sql, pars);
            if (result != null)
                return result.ToString();
            return null;
        }

        /// <summary>
        /// 根据用户名获取部门id
        /// </summary>
        /// <param name="name"></param>
        /// <returns></returns>
        public string GetDeptID(string name)
        {
            string sql = "select deptid from users where name=@name";
            SqlParameter[] pars ={
                                    new SqlParameter("@name",SqlDbType.VarChar,50)
                                    };
            pars[0].Value = name;
            object result = SqlHelper.ExecuteScalar(sql, pars);
            if (result != null)
                return result.ToString();
            return null;
        }

    }
}

转自：http://hi.baidu.com/wjr_loves/blog/item/cd64b26614aaf2cae6113a05.html