Asp.net(c#)数据库操作类

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 System.Data.SqlClient;
namespace Mysqlserver
{
/// <summary>
/// SqlServerDataBase 的摘要说明
/// </summary>
public class SqlServerDataBase
{
private string strError = null;
private int intCount = 0;
public SqlServerDataBase()
{
//
// TODO: 在此处添加构造函数逻辑
//
}
/// <summary>
/// 公开方法DBConn，返回数据库连接
/// </summary>
/// <returns></returns>
public SqlConnection DBconn()
{
string strConn = "Server=(local);Database=GlobalMeetings;Uid=sa;pwd=";
try
{
return new SqlConnection(strConn);
}
catch (Exception)
{
return null;
}
}
/// <summary>
/// 公开属性ErrorMessage，返回错误信息
/// </summary>
public string ErrorMessage
{
get
{
return strError;
}
}

/// <summary>
/// 根据查询语句从数据库检索数据
/// </summary>
/// <param name="strSelect">查询语句</param>
/// <param name="SqlConn">数据库连接</param>
/// <returns>有数据则返回DataSet对象，否则返回null</returns>
public DataSet Select(string SelectString, SqlConnection sqlConn)
{
strError = "";
SqlConnection conn;
if (sqlConn == null)
{
conn = DBconn();
}
else
{
conn = sqlConn;
}
try
{
//若数据库连接的当前状态是关闭的，则打开连接
if (conn.State == ConnectionState.Closed)
{
conn.Open();
}
SqlDataAdapter mySqlDataAdapter = new SqlDataAdapter();
SqlCommand selectCommand = new SqlCommand(SelectString, conn);
selectCommand.CommandType = CommandType.Text;
mySqlDataAdapter.SelectCommand = selectCommand;
DataSet myDS = new DataSet();
mySqlDataAdapter.Fill(myDS);
return myDS;
}
catch (Exception e)
{
strError = "数据检索失败：" + e.Message;
return null;
}
finally
{
if (conn.State != ConnectionState.Closed)
{
conn.Close();
}
}
}
/// <summary>
/// 更新数据库
/// </summary>
/// <param name="UpdateString">Update Sql语句</param>
/// <param name="SqlConn">数据库连接</param>
/// <returns>更新成功返回true</returns>
public bool Update(string UpdateString, SqlConnection SqlConn)
{
return udiDataBase(UpdateString, SqlConn);
}
/// <summary>
/// 从数据库中删除数据
/// </summary>
/// <param name="DeleteString">Delete Sql语句</param>
/// <param name="SqlConn">数据库连接</param>
/// <returns>删除成功返回true</returns>
public bool Delete(string DeleteString, SqlConnection SqlConn)
{
return udiDataBase(DeleteString, SqlConn);
}
/// <summary>
/// 把数据插入数据库
/// </summary>
/// <param name="InsertString">Insert Sql语句</param>
/// <param name="SqlConn">数据库连接</param>
/// <returns>插入成功返回true</returns>
public bool Insert(string InsertString, SqlConnection SqlConn)
{
return udiDataBase(InsertString, SqlConn);
}
/// <summary>
/// 根据Sql语句更新数据库
/// </summary>
/// <param name="UDIString">更新语句</param>
/// <param name="SqlConn">数据库连接</param>
/// <returns>更新成功则返回true</returns>
public bool udiDataBase(string UDIString, SqlConnection SqlConn)
{
strError = "";
SqlConnection conn;
if (SqlConn == null)
{
conn = DBconn();
}
else
{
conn = SqlConn;
}
try
{
if (conn.State == ConnectionState.Closed)
{
conn.Open();
}
SqlCommand cmd = new SqlCommand(UDIString, conn);
cmd.CommandType = CommandType.Text;
intCount = cmd.ExecuteNonQuery();
return !(intCount < 1);
}
catch (Exception e)
{
strError = "更新数据库失败：" + e.Message;
return false;
}
finally
{
if (conn.State != ConnectionState.Closed)
{
conn.Close();
}
}
}
}
}
-----------------------------
两种调用方法
1、 string strUserPsw = UserPsw.Text.Trim();
string UserPassword = System.Web.Security.FormsAuthentication.HashPasswordForStoringInConfigFile(strUserPsw, "MD5");//md5加密
SqlServerDataBase obj = new SqlServerDataBase();
obj.Insert("insert into asUserInfo (UserName,UserPassword,Question,Answer,CreateTime) values('" + UserName.Text.Trim() + "','" + UserPassword + "','" + Question.Text.Trim() + "','" + Answer.Text.Trim() + "','" + DateTime.Now.ToString() + "' )", null);
2、 private bool IsUsernameExist(string strUsername)
{
bool bRet = true;
SqlServerDataBase db = new SqlServerDataBase();
DataSet ds = db.Select("select * from asUserInfo where UserName = '" + strUsername + "'", null);
if (ds == null || ds.Tables.Count == 0 || ds.Tables[0].Rows.Count == 0)
{
bRet = false;
}
else
{
bRet = true;
}

return bRet;
}