using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Data.OleDb;
using System.Data;
using System.Windows.Forms;namespace MyCommanHelper
{public class DataBaseHelper{#region 字段变量public static volatile string Connstring = "";private static volatile OleDbConnection connection = null;#endregion#region 方法#region Access// Methods/// <summary>/// 获取Access2003连接字符串/// </summary>/// <param name="sFilePath">Access文件路径</param>/// <returns></returns>public static string GetAccess2003ConnectionString(string sFilePath){return ("Provider=Microsoft.JET.OLEDB.4.0;data source=" + sFilePath);}/// <summary>/// 获取Access2007连接字符串/// </summary>/// <param name="sFilePath">Access文件路径</param>/// <returns></returns>public static string GetAccess2007ConnectionString(string sFilePath){return ("Provider=Microsoft.ACE.OLEDB.12.0;Data Source=" + sFilePath);}#endregion#region SqlServer#endregion#region Oraclepublic static string GetOracleBlobConnectionString(string sUser, string sPassword, string sServiceName){return ("server=oratest;Data Source=" + sServiceName + ";User ID=" + sUser + ";Password=" + sPassword);}public static string GetOracleConnectionString(string sUser, string sPassword, string sServiceName){return ("Provider=OraOLEDB.Oracle.1;Data Source=" + sServiceName + ";User ID=" + sUser + ";Password=" + sPassword);}#endregion#region 公共/// <summary>/// 初始化新实例/// </summary>/// <returns></returns>public static bool Init(){try{connection = new OleDbConnection(Connstring);return true;}catch (Exception){return false;}}/// <summary>/// 执行非查询操作/// </summary>/// <param name="sqlStr">执行SQL语句</param>/// <returns>返回影响行数，值为-1 表示未创建连接实例或执行语句错误</returns>public static int ExecNonQuery(string sqlStr){int rslt = -1;if (null == connection){MessageBox.Show("无连接实例！");return rslt;}try{if (connection.State == ConnectionState.Closed){connection.Open();}OleDbCommand command = new OleDbCommand(sqlStr, connection);rslt = command.ExecuteNonQuery();command.Dispose();//connection.Close();//connection.Dispose();}catch (Exception ex){throw ex;}finally{connection.Close();}return rslt;}/// <summary>/// 获取只包含指定的数据的数据集/// </summary>/// <param name="sqlStr">Sql指令</param>/// <param name="sTable">指定数据</param>/// <returns>数据集 值为null 表示未创建连接实例</returns>public static DataSet ExecQuery(string sqlStr, string sTable){DataSet set2 = null;if (null == connection){MessageBox.Show("无连接实例！");return set2;}try{if (connection.State == ConnectionState.Closed){connection.Open();}OleDbDataAdapter adapter = new OleDbDataAdapter(sqlStr, connection);DataSet dataSet = new DataSet();if (dataSet.Tables.Contains(sTable)){dataSet.Tables[sTable].Clear();}adapter.Fill(dataSet, sTable);set2 = dataSet;}catch (Exception exception){throw exception;}finally{connection.Close();//connection.Dispose();//connection = null;}return set2;}/// <summary>/// 获得第一行数据/// </summary>/// <param name="sql"></param>/// <param name="sTable"></param>/// <returns></returns>public static DataRow GetFirstRow(string sql, string sTable){DataRow row = null;DataSet set = ExecQuery(sql, sTable);if (set.Tables[sTable].Rows.Count > 0){row = set.Tables[sTable].Rows[0];}return row;}/// <summary>/// 获得第一行第一个字段的值/// </summary>/// <param name="sql"></param>/// <param name="sTable"></param>/// <returns></returns>public static string GetFirstFieldValue(string sql, string sTable){string str = "";DataSet set = ExecQuery(sql, sTable);if (set.Tables[sTable].Rows.Count > 0){DataRow row = set.Tables[sTable].Rows[0];str = row[0].ToString();}return str;}/// <summary>/// 释放连接资源/// </summary>public static void Dispose(){if (null != connection){if (connection.State != ConnectionState.Closed){connection.Close();}connection.Dispose();connection = null;}}#endregion#endregion}
}