Accesss数据库的DBhelper类（带分页）

首先配置web.config，使配置文件连接access数据库：

<connectionStrings>

<add name="DBConnection" connectionString="Provider=Microsoft.Jet.Oledb.4.0;Data Source=|DataDirectory|#lcng.mdb" />  //数据库在本网站App_Data的文件夹中
</connectionStrings>

下面是DBhelper类：

 using System;
 using System.Collections.Generic;
 using System.Text;
 using System.Data;
 using System.Data.OleDb;
 using System.Configuration;
 using System.Reflection;
 using System.Security.Cryptography;

 public class DBHelper
 {
 public static string connectionString = ConfigurationManager.ConnectionStrings["DBConnection"].ConnectionString;
 //不带参数的执行命令
 public static int ExecuteCommand(string safeSql)
 {
 using (OleDbConnection connection = new OleDbConnection(connectionString))
 {
 connection.Open();
 OleDbCommand cmd = new OleDbCommand(safeSql, connection);
 return cmd.ExecuteNonQuery();
 }
 }
 //带参数的执行命令
 public static int ExecuteCommand(string sql, params OleDbParameter[] values)
 {
 using (OleDbConnection connection = new OleDbConnection(connectionString))
 {
 connection.Open();
 OleDbCommand cmd = new OleDbCommand(sql, connection);
 cmd.Parameters.AddRange(values);
 return cmd.ExecuteNonQuery();
 }
 }

 public static int GetScalar(string safeSql)
 {
 using (OleDbConnection connection = new OleDbConnection(connectionString))
 {
 connection.Open();
 OleDbCommand cmd = new OleDbCommand(safeSql, connection);
 return Convert.ToInt32(cmd.ExecuteScalar());
 }
 }
 /// <summary>
 /// 得到一个字段的值
 /// </summary>
 /// <param name="sql"></param>
 /// <returns></returns>
 public static string GetOneValue(string sql)
 {
 using (OleDbConnection connection = new OleDbConnection(connectionString))
 {
 connection.Open();
 using (OleDbCommand cmd = new OleDbCommand(sql, connection))
 {
 object obj = cmd.ExecuteScalar();
 cmd.Prepare();
 return obj != null ? obj.ToString() : string.Empty;
 }
 }
 }

 public static int GetScalar(string sql, params OleDbParameter[] values)
 {
 using (OleDbConnection connection = new OleDbConnection(connectionString))
 {
 connection.Open();
 OleDbCommand cmd = new OleDbCommand(sql, connection);
 cmd.Parameters.AddRange(values);
 return Convert.ToInt32(cmd.ExecuteScalar());
 }
 }

 public static OleDbDataReader GetReader(string safeSql)
 {
 OleDbConnection connection = new OleDbConnection(connectionString);
 connection.Open();
 OleDbCommand cmd = new OleDbCommand(safeSql, connection);
 return cmd.ExecuteReader(CommandBehavior.CloseConnection);
 }

 public static OleDbDataReader GetReader(string sql, params OleDbParameter[] values)
 {
 OleDbConnection connection = new OleDbConnection(connectionString);
 connection.Open();
 OleDbCommand cmd = new OleDbCommand(sql, connection);
 cmd.Parameters.AddRange(values);
 return cmd.ExecuteReader(CommandBehavior.CloseConnection);
 }

 public static DataSet GetDataSet(string safeSql)
 {
 using (OleDbConnection connection = new OleDbConnection(connectionString))
 {
 DataSet ds = new DataSet();
 OleDbCommand cmd = new OleDbCommand(safeSql, connection);
 OleDbDataAdapter da = new OleDbDataAdapter(cmd);
 da.Fill(ds);
 return ds;
 }
 }

 public static DataTable GetDataSet(string sql, params OleDbParameter[] values)
 {
 using (OleDbConnection connection = new OleDbConnection(connectionString))
 {
 DataSet ds = new DataSet();
 OleDbCommand cmd = new OleDbCommand(sql, connection);
 cmd.Parameters.AddRange(values);
 OleDbDataAdapter da = new OleDbDataAdapter(cmd);
 da.Fill(ds);
 return ds.Tables[];
 }
 }
 /// <summary>
 /// 分页使用
 /// </summary>
 /// <param name="query"></param>
 /// <param name="passCount"></param>
 /// <returns></returns>
 private static string recordID(string query, int passCount)
 {
 using (OleDbConnection m_Conn = new OleDbConnection(connectionString))
 {
 m_Conn.Open();
 OleDbCommand cmd = new OleDbCommand(query, m_Conn);
 string result = string.Empty;
 using (OleDbDataReader dr = cmd.ExecuteReader())
 {
 while (dr.Read())
 {
 if (passCount < )
 {
 result += "," + dr.GetInt32();
 }
 passCount--;
 }
 }
 m_Conn.Close();
 m_Conn.Dispose();
 return result.Substring();
 }
 }
 /// <summary>
 /// ACCESS高效分页
 /// </summary>
 /// <param name="pageIndex">当前页码</param>
 /// <param name="pageSize">分页容量</param>
 /// <param name="strKey">主键</param>
 /// <param name="showString">显示的字段</param>
 /// <param name="queryString">查询字符串，支持联合查询</param>
 /// <param name="whereString">查询条件，若有条件限制则必须以where 开头</param>
 /// <param name="orderString">排序规则</param>
 /// <param name="pageCount">传出参数：总页数统计</param>
 /// <param name="recordCount">传出参数：总记录统计</param>
 /// <returns>装载记录的DataTable</returns>
 public static DataTable ExecutePager(int pageIndex, int pageSize, string strKey, string showString, string queryString, string whereString, string orderString, out int pageCount, out int recordCount)
 {
 if (pageIndex < ) pageIndex = ;
 if (pageSize < ) pageSize = ;
 if (string.IsNullOrEmpty(showString)) showString = "*";
 if (string.IsNullOrEmpty(orderString)) orderString = strKey + " asc ";
 using (OleDbConnection m_Conn = new OleDbConnection(connectionString))
 {
 m_Conn.Open();
 string myVw = string.Format(" ( {0} ) tempVw ", queryString);
 string where1 = string.Empty;
 if (String.IsNullOrEmpty(whereString))
 {
 where1 = "";
 }
 else
 {
 where1 = whereString.Trim();
 if (where1.StartsWith("and", StringComparison.CurrentCultureIgnoreCase))
 {
 where1 = where1.Substring();
 }
 }
 string where2 = String.IsNullOrEmpty(where1) ? "" : "where " + where1;
 OleDbCommand cmdCount = new OleDbCommand(string.Format(" select count(*) as recordCount from {0} {1}", myVw, where2), m_Conn);
 recordCount = Convert.ToInt32(cmdCount.ExecuteScalar());
 if ((recordCount % pageSize) > )
 pageCount = recordCount / pageSize + ;
 else
 pageCount = recordCount / pageSize;
 OleDbCommand cmdRecord;
 if (pageIndex == )//第一页
 {
 cmdRecord = new OleDbCommand(string.Format("select top {0} {1} from {2} {3} order by {4} ", pageSize, showString, myVw, where2, orderString), m_Conn);
 }
 else if (pageIndex > pageCount)//超出总页数
 {
 cmdRecord = new OleDbCommand(string.Format("select top {0} {1} from {2} {3} order by {4} ", pageSize, showString, myVw, "where 1=2", orderString), m_Conn);
 }
 else
 {
 int pageLowerBound = pageSize * pageIndex;
 int pageUpperBound = pageLowerBound - pageSize;
 string recordIDs = recordID(string.Format("select top {0} {1} from {2} {3} order by {4} ", pageLowerBound, strKey, myVw, where2, orderString), pageUpperBound);
 cmdRecord = new OleDbCommand(string.Format("select {0} from {1} where {2} in ({3}) order by {4} ", showString, myVw, strKey, recordIDs, orderString), m_Conn);

 }
 OleDbDataAdapter dataAdapter = new OleDbDataAdapter(cmdRecord);
 DataTable dt = new DataTable();
 dataAdapter.Fill(dt);
 m_Conn.Close();
 m_Conn.Dispose();
 return dt;
 }
 }
 /// <summary>
 /// MD5加密
 /// </summary>
 /// <param name="str"></param>
 /// <returns></returns>
 public static string MD5DecryptString(string str)
 {
 MD5CryptoServiceProvider md5 = new MD5CryptoServiceProvider();
 byte[] md5Source = System.Text.Encoding.UTF8.GetBytes(str);
 byte[] md5Out = md5.ComputeHash(md5Source);
 return Convert.ToBase64String(md5Out);
 }

 /// <summary>
 /// DES加密字符串
 /// </summary>
 /// <param name="sInputString">输入字符</param>
 /// <param name="sKey">Key</param>
 /// <returns>加密结果</returns>
 public string DESEncryptString(string sInputString, string sKey)
 {
 try
 {
 byte[] data = Encoding.Default.GetBytes(sInputString);
 byte[] result;
 DESCryptoServiceProvider DES = new DESCryptoServiceProvider();
 DES.Key = ASCIIEncoding.ASCII.GetBytes(sKey); //密钥
 DES.IV = ASCIIEncoding.ASCII.GetBytes(sKey); //初始化向量
 ICryptoTransform desencrypt = DES.CreateEncryptor(); //加密器对象
 result = desencrypt.TransformFinalBlock(data, , data.Length); //转换指定字节数组的指定区域
 return BitConverter.ToString(result);
 }
 catch (Exception ex)
 {
 //ex.Message = "DES加密异常";
 throw ex;
 }
 }
 /// <summary>
 /// DES解密字符串
 /// </summary>
 /// <param name="sInputString">输入字符</param>
 /// <param name="sKey">Key</param>
 /// <returns>解密结果</returns>
 public string DESDecryptString(string sInputString, string sKey)
 {
 try
 {
 //将字符串转换为字节数组
 string[] sInput = sInputString.Split("-".ToCharArray());
 byte[] data = new byte[sInput.Length];
 byte[] result;
 for (int i = ; i < sInput.Length; i++)
 {
 data[i] = byte.Parse(sInput[i], System.Globalization.NumberStyles.HexNumber);
 }

 DESCryptoServiceProvider DES = new DESCryptoServiceProvider();
 DES.Key = ASCIIEncoding.ASCII.GetBytes(sKey);
 DES.IV = ASCIIEncoding.ASCII.GetBytes(sKey);
 ICryptoTransform desencrypt = DES.CreateDecryptor();
 result = desencrypt.TransformFinalBlock(data, , data.Length);
 return Encoding.Default.GetString(result);
 }
 catch (Exception ex)
 {
 //ex.Message = "DES解密异常";
 throw ex;
 }
 }
 }