asp.net 数据库的连接和datatable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;
/// <summary>
/// sqlconnections 的摘要说明
/// </summary>
namespace system.mysqlconnection
{
public class sqlconnections
{
//当前连接的是第几个。
static int count = 0;
//最大连接量
static int maxcount = 30;
static sqlconnection[] sqlconns = new sqlconnection[maxcount];
//自己创建自己
static sqlconnections myconn = new sqlconnections();
//初始化
private sqlconnections()
{
for (int i = 0; i < maxcount; i++)
{
sqlconns[i] = new sqlconnection(system.configuration.configurationsettings.appsettings["adostr"].tostring());
}
}
//根据条件来获取不同的表，与字段。
public static datatable getdatatable(string sqltest, string tablename)
{
try
{
dataset myds = new dataset();
sqldataadapter myadapater = new sqldataadapter(sqltest, sqlconnections.getsqlconnection());
myadapater.fill(myds, tablename);
return myds.tables[tablename];
}
catch (sqlexception sqle)
{
return null;
}
}
// 获取数据库连接
public static sqlconnection getsqlconnection()
{
try
{
try
{
sqlconns[count].close();
}
catch (exception eex)
{
}
return sqlconns[count];
}
finally
{
//当前个数自加。。
if (count == (maxcount - 1))
{
count = 0;
}
else
{
count++;
}
}
}
//返回一个参数
public static string getnumonefield(string sqltxt)
{
sqlconnection sqlconntemp = sqlconnections.getsqlconnection();
try
{
sqlcommand sqlcommt = new sqlcommand(sqltxt, sqlconntemp);
sqlconntemp.open();
return sqlcommt.executescalar().tostring();
}
catch (exception sqle)
{
return "没有";
}
finally
{
sqlconntemp.close();
}
}
//返回一个参数
public static string getnumonefield(sqlconnection sqlconntemp,sqltransaction tempsqltran ,string sqltxt)
{
try
{
sqlcommand sqlcommt = new sqlcommand(sqltxt, sqlconntemp);
sqlcommt.transaction = tempsqltran;
return sqlcommt.executescalar().tostring();
}
catch (exception sqle)
{
return "没有";
}
finally
{
//sqlconntemp.close();
}
}
/// <summary>
/// 做 ，修改，删除，
/// </summary>
/// <param name="sqltxt">执行的sql语句</param>
/// <returns>返回的结果影响多少行</returns>
public static int updateordelete(string sqltxt)
{
sqlconnection sqlconntemp = sqlconnections.getsqlconnection();
try
{
sqlcommand sqlcommt = new sqlcommand(sqltxt, sqlconntemp);
sqlconntemp.open();
return sqlcommt.executenonquery();
}
catch (sqlexception sqle)
{
return 0;
}
finally
{
//sqlconntemp.close();
}
}
public static int updateordelete(commandtype _commandtype, sqlparameter[] _sqlparas, string sqltxt)
{
sqlconnection sqlconntemp = sqlconnections.getsqlconnection();
try
{
sqlcommand sqlcommt = new sqlcommand(sqltxt, sqlconntemp);
sqlcommt.commandtype = _commandtype;
sqlcommt.parameters.clear();
for (int a = 0; a < _sqlparas.length; a++)
{
sqlcommt.parameters.add(_sqlparas[a]);
}
sqlconntemp.open();
return sqlcommt.executenonquery();
}
catch (sqlexception sqle)
{
return 0;
}
finally
{
//sqlconntemp.close();
}
}
/// <summary>
/// 带事务的增，删，改数据执行方法(警告：该方法必须 手动开关数据,而且还有手动的提交事务。否则不能更新数据)
/// </summary>
/// <param name="_sqlconn">数据库连接对象</param>
/// <param name="_sqltran">事务对象</param>
/// <param name="sqltxt">执行的sql语句</param>
/// <returns></returns>
public static int updateordelete(sqlconnection _sqlconn,sqltransaction _sqltran, string sqltxt)
{
sqlconnection sqlconntemp = _sqlconn;
try
{
sqlcommand sqlcommt = new sqlcommand(sqltxt, sqlconntemp);
sqlcommt.transaction = _sqltran;
sqlconntemp.open();
return sqlcommt.executenonquery();
}
catch (sqlexception sqle)
{
return 0;
}
finally
{
//sqlconntemp.close();
}
}
public static int updateordelete(sqlconnection _sqlconn, sqltransaction _sqltran, commandtype _commandtype, sqlparameter [] _sqlparas, string sqltxt)
{
sqlconnection sqlconntemp = _sqlconn;
try
{
sqlcommand sqlcommt = new sqlcommand(sqltxt, sqlconntemp);
sqlcommt.transaction = _sqltran;
sqlcommt.commandtype = _commandtype;
sqlcommt.parameters.clear();
for (int a = 0; a < _sqlparas.length; a++)
{
sqlcommt.parameters.add(_sqlparas[a]);
}
return sqlcommt.executenonquery();
}
catch (sqlexception sqle)
{
return 0;
}
finally
{
// sqlconntemp.close();
}
}
/// <summary>
/// 有存储过的查询
/// </summary>
/// <param name="storedprocedurename">存储过程的名字</param>
/// <param name="sqlparas">所有参数</param>
/// <param name="tablename">表名</param>
/// <returns>datatable的结果集</returns>
public static datatable getdatatable(string storedprocedurename, sqlparameter [] sqlparas,string tablename)
{
try
{
dataset myds = new dataset();
sqldataadapter myadapater = new sqldataadapter(storedprocedurename, sqlconnections.getsqlconnection());
myadapater.selectcommand.commandtype = commandtype.storedprocedure;
for (int i = 0; i < sqlparas.length; i++)
{
//if (myadapater.selectcommand.parameters.contains(sqlparas[i]))
//myadapater.selectcommand.parameters.removeat(sqlparas[i].parametername);
myadapater.selectcommand.parameters.add(sqlparas[i]);
}
myadapater.fill(myds, tablename);
myadapater.selectcommand.parameters.clear();
myadapater.dispose();
return myds.tables[tablename];
}
catch (sqlexception sqle)
{
return null;
}
}
}
}