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C# mysql读取类

 using System;
using System.Data;
using System.Configuration;
using System.Web;
using System.Web.Security;
using System.Web.UI;
using System.Web.UI.WebControls;
using System.Web.UI.WebControls.WebParts;
using System.Web.UI.HtmlControls;
using MySql.Data.Types;
using MySql.Data.MySqlClient;
/// <summary>
/// C#操作mysql基类
/// </summary>
public class MySqlobj
{
private MySqlConnection conn;
private MySqlCommand com;
private bool _alreadyDispose = false;
#region 构造与柝构
public MySqlobj()
{
try
{
conn = new MySqlConnection(ConfigurationManager.AppSettings["mysqlconn"]);
conn.Open();
com = new MySqlCommand();
com.Connection = conn;
}
catch (Exception ee)
{
throw new Exception("连接数据库出错");
}
}
~MySqlobj()
{
Dispose();
}
protected virtual void Dispose(bool isDisposing)
{
if (_alreadyDispose) return;
if (isDisposing)
{
// TODO: 此处释放受控资源
if (com != null)
{

com.Dispose();
}
if (conn != null)
{
try
{
conn.Close();
conn.Dispose();
}
catch (Exception ee)
{
}
finally
{
conn = null;
}
}
}
// TODO: 此处释放非受控资源。设置被处理过标记
_alreadyDispose = true;
}
#endregion
#region IDisposable 成员
public void Dispose()
{
Dispose(true);
GC.SuppressFinalize(this);
}
#endregion
#region 获取DataSet
public DataSet GetDataSet(string sqlString)
{
DataSet ds = new DataSet();
try


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