C# MySqlHelper

1、MySql官方提供ADO.NET访问模式的MySql.Data.dll，下载地址：http://dev.mysql.com/downloads/connector/net/

2、MySqlHelper，如下：

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Data;
using MySql.Data.MySqlClient;

namespace drWm.mdal
{
public class MySqlHelper
{
//private static string connstr = @"server=localhost;uid=root;pwd=121535;database=tem;charset=utf8";
private static string connstr = @"Host=127.0.0.1;UserName=root;Password=drpassword;Database=watermonitor;Port=3406;CharSet=utf8;Allow Zero Datetime=true";

#region 执行查询语句，返回MySqlDataReader
/// <summary>
/// 执行查询语句，返回MySqlDataReader
/// </summary>
/// <param name="sqlString"></param>
/// <returns></returns>
public static MySqlDataReader ExecuteReader(string sqlString)
{
MySqlConnection connection = new MySqlConnection(connstr);
MySqlCommand cmd = new MySqlCommand(sqlString, connection);
MySqlDataReader myReader = null;
try
{
connection.Open();
myReader = cmd.ExecuteReader(CommandBehavior.CloseConnection);
return myReader;
}
catch (System.Data.SqlClient.SqlException e)
{
connection.Close();
throw new Exception(e.Message);
}
finally
{
if (myReader == null)
{
cmd.Dispose();
connection.Close();
}
}
}
#endregion

#region 执行带参数的查询语句，返回MySqlDataReader
/// <summary>
/// 执行带参数的查询语句，返回MySqlDataReader
/// </summary>
/// <param name="sqlString"></param>
/// <param name="cmdParms"></param>
/// <returns></returns>
public static MySqlDataReader ExecuteReader(string sqlString, params MySqlParameter[] cmdParms)
{
MySqlConnection connection = new MySqlConnection(connstr);
MySqlCommand cmd = new MySqlCommand();
MySqlDataReader myReader = null;
try
{
PrepareCommand(cmd, connection, null, sqlString, cmdParms);
myReader = cmd.ExecuteReader(CommandBehavior.CloseConnection);
cmd.Parameters.Clear();
return myReader;
}
catch (System.Data.SqlClient.SqlException e)
{
connection.Close();
throw new Exception(e.Message);
}
finally
{
if (myReader == null)
{
cmd.Dispose();
connection.Close();
}
}
}
#endregion

#region 执行sql语句,返回执行行数
/// <summary>
/// 执行sql语句,返回执行行数
/// </summary>
/// <param name="sql"></param>
/// <returns></returns>
public static int ExecuteSql(string sql)
{
using (MySqlConnection conn = new MySqlConnection(connstr))
{
using (MySqlCommand cmd = new MySqlCommand(sql, conn))
{
try
{
conn.Open();
int rows = cmd.ExecuteNonQuery();
return rows;
}
catch (MySql.Data.MySqlClient.MySqlException e)
{
conn.Close();
throw e;
}
finally
{
cmd.Dispose();
conn.Close();
}
}
}
}
#endregion

#region 执行带参数的sql语句，并返回执行行数
/// <summary>
/// 执行带参数的sql语句，并返回执行行数
/// </summary>
/// <param name="sqlString"></param>
/// <param name="cmdParms"></param>
/// <returns></returns>
public static int ExecuteSql(string sqlString, params MySqlParameter[] cmdParms)
{
using (MySqlConnection connection = new MySqlConnection(connstr))
{
using (MySqlCommand cmd = new MySqlCommand())
{
try
{
PrepareCommand(cmd, connection, null, sqlString, cmdParms);
int rows = cmd.ExecuteNonQuery();
cmd.Parameters.Clear();
return rows;
}
catch (System.Data.SqlClient.SqlException E)
{
throw new Exception(E.Message);
}
finally
{
cmd.Dispose();
connection.Close();
}
}
}
}
#endregion

#region 执行查询语句，返回DataSet
/// <summary>
/// 执行查询语句，返回DataSet
/// </summary>
/// <param name="sql"></param>
/// <returns></returns>
public static DataSet GetDataSet(string sql)
{
using (MySqlConnection conn = new MySqlConnection(connstr))
{
DataSet ds = new DataSet();
try
{
conn.Open();
MySqlDataAdapter DataAdapter = new MySqlDataAdapter(sql, conn);
DataAdapter.Fill(ds);
}
catch (Exception ex)
{
throw ex;
}
finally
{
conn.Close();
}
return ds;
}
}
#endregion

#region 执行带参数的查询语句，返回DataSet
/// <summary>
/// 执行带参数的查询语句，返回DataSet
/// </summary>
/// <param name="sqlString"></param>
/// <param name="cmdParms"></param>
/// <returns></returns>
public static DataSet GetDataSet(string sqlString, params MySqlParameter[] cmdParms)
{
using (MySqlConnection connection = new MySqlConnection(connstr))
{
MySqlCommand cmd = new MySqlCommand();
PrepareCommand(cmd, connection, null, sqlString, cmdParms);
using (MySqlDataAdapter da = new MySqlDataAdapter(cmd))
{
DataSet ds = new DataSet();
try
{
da.Fill(ds, "ds");
cmd.Parameters.Clear();
}
catch (System.Data.SqlClient.SqlException ex)
{
throw new Exception(ex.Message);
}
finally
{
cmd.Dispose();
connection.Close();
}
return ds;
}
}
}
#endregion

#region 执行带参数的sql语句，并返回object
/// <summary>
/// 执行带参数的sql语句，并返回object
/// </summary>
/// <param name="sqlString"></param>
/// <param name="cmdParms"></param>
/// <returns></returns>
public static object GetSingle(string sqlString, params MySqlParameter[] cmdParms)
{
using (MySqlConnection connection = new MySqlConnection(connstr))
{
using (MySqlCommand cmd = new MySqlCommand())
{
try
{
PrepareCommand(cmd, connection, null, sqlString, cmdParms);
object obj = cmd.ExecuteScalar();
cmd.Parameters.Clear();
if ((Object.Equals(obj, null)) || (Object.Equals(obj, System.DBNull.Value)))
{
return null;
}
else
{
return obj;
}
}
catch (System.Data.SqlClient.SqlException e)
{
throw new Exception(e.Message);
}
finally
{
cmd.Dispose();
connection.Close();
}
}
}
}
#endregion

/// <summary>
/// 执行存储过程,返回数据集
/// </summary>
/// <param name="storedProcName">存储过程名</param>
/// <param name="parameters">存储过程参数</param>
/// <returns>DataSet</returns>
public static DataSet RunProcedureForDataSet(string storedProcName, IDataParameter[] parameters)
{
using (MySqlConnection connection = new MySqlConnection(connstr))
{
DataSet dataSet = new DataSet();
connection.Open();
MySqlDataAdapter sqlDA = new MySqlDataAdapter();
sqlDA.SelectCommand = BuildQueryCommand(connection, storedProcName, parameters);
sqlDA.Fill(dataSet);
connection.Close();
return dataSet;
}
}

/// <summary>
/// 构建 SqlCommand 对象(用来返回一个结果集，而不是一个整数值)
/// </summary>
/// <param name="connection">数据库连接</param>
/// <param name="storedProcName">存储过程名</param>
/// <param name="parameters">存储过程参数</param>
/// <returns>SqlCommand</returns>
private static MySqlCommand BuildQueryCommand(MySqlConnection connection, string storedProcName,
IDataParameter[] parameters)
{
MySqlCommand command = new MySqlCommand(storedProcName, connection);
command.CommandType = CommandType.StoredProcedure;
foreach (MySqlParameter parameter in parameters)
{
command.Parameters.Add(parameter);
}
return command;
}

#region 装载MySqlCommand对象
/// <summary>
/// 装载MySqlCommand对象
/// </summary>
private static void PrepareCommand(MySqlCommand cmd, MySqlConnection conn, MySqlTransaction trans, string cmdText,
MySqlParameter[] cmdParms)
{
if (conn.State != ConnectionState.Open)
{
conn.Open();
}
cmd.Connection = conn;
cmd.CommandText = cmdText;
if (trans != null)
{
cmd.Transaction = trans;
}
cmd.CommandType = CommandType.Text; //cmdType;
if (cmdParms != null)
{
foreach (MySqlParameter parm in cmdParms)
{
cmd.Parameters.Add(parm);
}
}
}
#endregion

}
}