用于MySql数据库的MySqlHelper.cs类,及其调用例子

封云亭

　　先下载 MySql.Data.dll，把它引用到项目中
　　下载地址： http://www.dllzj.com/Down_MySql.Data.dll.html
　　
using System;using System.Collections.Generic;using System.Linq;using System.Text;using System.Data;using MySql.Data.MySqlClient;using System.Configuration;namespace JonseTest{public class MySqlHelper{public static string ConnString = "";public static string Conn_Config_Str_Name = string.Empty;public static string Conn_Server = string.Empty;public static string Conn_DBName = string.Empty;public static string Conn_Uid = string.Empty;public static string Conn_Pwd = string.Empty;private static string _ConnString{get{if (!string.IsNullOrEmpty(ConnString))return ConnString;object oConn = ConfigurationManager.ConnectionStrings[Conn_Config_Str_Name];if (oConn != null && oConn.ToString() != "")return oConn.ToString();return string.Format(@"server={0};database={1};userid={2};password={3}", Conn_Server, Conn_DBName, Conn_Uid, Conn_Pwd);}}// 读取数据 datatablepublic static DataTable GetDataTable(out string sError,string sSQL){DataTable dt = null;sError = string.Empty;MySqlConnection myConn = null;try{myConn = new MySqlConnection(_ConnString);MySqlCommand myCommand = new MySqlCommand(sSQL, myConn);myConn.Open();MySqlDataAdapter adapter = new MySqlDataAdapter(myCommand);dt = new DataTable();adapter.Fill(dt);myConn.Close();}catch (Exception ex){sError = ex.Message;}return dt;}// 读取数据 datasetpublic static DataSet GetDataSet(out string sError, string sSQL){DataSet ds = null;sError = string.Empty;MySqlConnection myConn = null;try{myConn = new MySqlConnection(_ConnString);MySqlCommand myCmd = new MySqlCommand(sSQL, myConn);myConn.Open();MySqlDataAdapter adapter = new MySqlDataAdapter(myCmd);ds = new DataSet();adapter.Fill(ds);myConn.Close();}catch (Exception ex){sError = ex.Message;}return ds;}// 取最大的IDpublic static Int32 GetMaxID(out string sError, string sKeyField, string sTableName){DataTable dt = GetDataTable(out sError, "select IFNULL(max(" + sKeyField + "),0) as MaxID from " + sTableName );if (dt != null && dt.Rows.Count > 0){return Convert.ToInt32(dt.Rows[0][0].ToString());}return 0;}// 插入，修改，删除，是否使用事务public static bool UpdateData(out string sError, string sSQL,bool bUseTransaction=false){int iResult=0;sError=string.Empty;MySqlConnection myConn = null;if (!bUseTransaction){try{myConn = new MySqlConnection(_ConnString);MySqlCommand myCmd = new MySqlCommand(sSQL, myConn);myConn.Open();iResult = myCmd.ExecuteNonQuery();myConn.Close();}catch (Exception ex){sError = ex.Message;iResult = -1;}}else // 使用事务{MySqlTransaction myTrans = null;try{myConn = new MySqlConnection(_ConnString);myConn.Open();myTrans = myConn.BeginTransaction();MySqlCommand myCmd = new MySqlCommand(sSQL, myConn);myCmd.Transaction = myTrans;iResult = myCmd.ExecuteNonQuery();myTrans.Commit();myConn.Close();}catch (Exception ex){sError = ex.Message;iResult = -1;myTrans.Rollback();}}return iResult>0;}}}　　
MySqlHelper类的调用方法与SqlServerHelper类的调用非常相似，请参考:
　　用于SqlServer数据库的SqlServerHelper.cs类，及其调用例子
　　网址： http://blog.csdn.net/keenweiwei/article/details/6845709
　　
　　注意 App.Config中，connectionString 中的是 userid ,不是uid
　　
　　<?xml version="1.0" encoding="utf-8" ?>
<configuration>
<connectionStrings>
<add name="ConnString" connectionString="server=电脑名 或 电脑IP;database=数据库名;userid=数据库登录名;password=数据库登录密码" />
</connectionStrings>
</configuration>