一个ASP.NET的MYSQL的数据库操作类自己封装的

/** 
* 类说明：对mysql数据库的操作类 
*/ 
using system; 
using system.data; 
using mysql.data.mysqlclient; 


namespace niunan.bylw.utility 
{ 
/// <summary>对mysql数据库的操作类 
/// 
/// </summary> 
public class mysqlhelper 
{ 
private mysqlconnection conn = null; 
private mysqlcommand cmd = null; 
private mysqldatareader sdr = null; 


public mysqlhelper() 
{ 
//string connstr = webconfigurationmanager.connectionstrings["connstr"].tostring(); 
string connstr = "server=localhost;database=test;uid=root;pwd=123456;charset=utf8"; 
conn = new mysqlconnection(connstr); 
} 


/// <summary>创建command对象 
/// 
/// </summary> 
/// <param name="sql">sql语句</param> 
public void createcommand(string sql) 
{ 
conn.open(); 
cmd = new mysqlcommand(sql, conn); 
} 


/// <summary>添加参数 
/// 
/// </summary> 
/// <param name="paramname">参数名称</param> 
/// <param name="value">值</param> 
public void addparameter(string paramname, object value) 
{ 
cmd.parameters.add(new mysqlparameter(paramname, value)); 
} 


/// <summary>执行不带参数的增删改sql语句 
/// 
/// </summary> 
/// <param name="cmdtext">增删改sql语句</param> 
/// <param name="ct">命令类型</param> 
/// <returns></returns> 
public bool executenonquery() 
{ 
int res; 
try 
{ 
res = cmd.executenonquery(); 
if (res > 0) 
{ 
return true; 
} 
} 
catch (exception ex) 
{ 
throw ex; 
} 
finally 
{ 
if (conn.state == connectionstate.open) 
{ 
conn.close(); 
} 
} 
return false; 
} 


/// <summary>执行查询sql语句 
/// 
/// </summary> 
/// <param name="cmdtext">查询sql语句</param> 
/// <returns></returns> 
public datatable executequery() 
{ 
datatable dt = new datatable(); 
using (sdr = cmd.executereader(commandbehavior.closeconnection)) 
{ 
dt.load(sdr); 
} 
return dt; 
} 


/// <summary>返回查询sql语句查询出的结果的第一行第一列的值 
/// 
/// </summary> 
/// <returns></returns> 
public string executescalar() 
{ 
string res = ""; 
try 
{ 
object obj = cmd.executescalar(); 
if (obj != null) 
{ 
res = obj.tostring(); 
} 
} 
catch (exception ex) 
{ 
throw ex; 
} 
finally 
{ 
if (conn.state == connectionstate.open) 
{ 
conn.close(); 
} 
} 
return res; 
} 
} 
} 

都是把那个sqlitehelper的操作类搬过来的，改了mysqlconnection等变量名，对mysql来说经常会出现中文乱码，经实验，解决方法：

① 用phpmyadmin建立mysql数据库的时候记得选择utf-8的编码

② 在上面的数据库操作类中的连接字符串中记得加上charset=utf8

这样用上面的操作类来插入中文就不会出现乱码了。