using?System;
using?System.Collections.Generic;
using?System.Linq;
using?System.Text;
using?System.Data;
using?System.Data.SqlClient;
using?System.Configuration;

namespace?ClassLibrary1
{
????class?DBHelper
????{
????????private?static?SqlConnection?_conn;
????????public?static?SqlConnection?Conn
????????{
????????????get
????????????{
????????????????string?connstr?=?ConfigurationManager.ConnectionStrings[“connstr“].ConnectionString;
????????????????if?（_conn?==?null）
????????????????{
????????????????????_conn?=?new?SqlConnection（connstr）;
????????????????????_conn.Open（）;
????????????????}
????????????????else?if?（_conn.State?==?ConnectionState.Closed）
????????????????{
????????????????????_conn.Open（）;
????????????????}
????????????????else?if?（_conn.State?==?ConnectionState.Broken）
????????????????{
????????????????????_conn.Close（）;
????????????????????_conn.Open（）;
????????????????}
????????????????return?_conn;
????????????}
????????}
????????///?

????????///?執行插入/更新/刪除
????????///?

????????///?
????????public?static?int?ExecuteCommand（string?sql）
????????{
????????????SqlCommand?cmd?=?new?SqlCommand（sql?Conn）;
????????????int?count?=?cmd.ExecuteNonQuery（）;
????????????return?count;
????????}
????????///?

????????///?執行查詢以連接的方式
????????///?

????????///?
????????public?static?SqlDataReader?getReader（string?sql）
????????{
????????????SqlCommand?cmd?=?new?SqlCommand（sql?Conn）;
????????????SqlDataReader?sdr?=?cmd.ExecuteReader（）;
????????????return?sdr;
????????}
????????///?

????????///?以不連接的方式操作數據庫
????????///?

????????///?
????????///?
????????public?static?DataTable?getDataSet（string?sql）
????????{
????????????SqlDataAdapter?sda?=?new?SqlDataAdapter（sql?Conn）;
????????????DataTable?dt?=?new?DataTable（）;
????????????sda.Fill（dt）;
????????????return?dt;
????????}
????????///?

????????///?返回首行首列的數據
????????///?

????????///?
????????///?
????????public?static?object?getScalar（string?sql）
????????{
????????????SqlCommand?cmd?=?new?SqlCommand（sql?Conn）;
????????????object?obj?=?cmd.ExecuteScalar（）;
????????????return?obj;
????????}
????}
}

?屬性????????????大小?????日期????時間???名稱
-----------?---------??----------?-----??----

?????文件??????10240??2014-04-25?12:19??ClassLibrary1\ClassLibrary1\bin\Debug\ClassLibrary1.dll

?????文件??????26112??2014-04-25?12:19??ClassLibrary1\ClassLibrary1\bin\Debug\ClassLibrary1.pdb

?????文件???????7680??2014-04-25?12:19??ClassLibrary1\ClassLibrary1\bin\Debug\lbjMod.dll

?????文件??????32256??2014-04-25?12:19??ClassLibrary1\ClassLibrary1\bin\Debug\lbjMod.pdb

?????文件???????2797??2014-04-25?00:44??ClassLibrary1\ClassLibrary1\ClassLibrary1.csproj

?????文件???????2462??2014-04-16?01:34??ClassLibrary1\ClassLibrary1\DBHelper.cs

?????文件????????642??2014-04-25?11:30??ClassLibrary1\ClassLibrary1\dengjiService.cs

?????文件???????2179??2014-04-25?00:17??ClassLibrary1\ClassLibrary1\gonggaoService.cs

?????文件???????1836??2014-04-25?12:01??ClassLibrary1\ClassLibrary1\jingjiaService.cs

?????文件????????444??2014-04-25?12:01??ClassLibrary1\ClassLibrary1\jingpianService.cs

?????文件????????664??2014-04-25?12:19??ClassLibrary1\ClassLibrary1\obj\Debug\ClassLibrary1.csproj.FileListAbsolute.txt

?????文件??????10240??2014-04-25?12:19??ClassLibrary1\ClassLibrary1\obj\Debug\ClassLibrary1.dll

?????文件??????26112??2014-04-25?12:19??ClassLibrary1\ClassLibrary1\obj\Debug\ClassLibrary1.pdb

?????文件???????5921??2014-04-25?16:07??ClassLibrary1\ClassLibrary1\obj\Debug\DesignTimeResolveAssemblyReferencesInput.cache

?????文件????????664??2014-04-20?11:01??ClassLibrary1\ClassLibrary1\obj\Debug\lbjDAL.csproj.FileListAbsolute.txt

?????文件???????2646??2014-04-25?12:19??ClassLibrary1\ClassLibrary1\obj\Debug\ResolveAssemblyReference.cache

?????文件???????1376??2014-04-16?00:39??ClassLibrary1\ClassLibrary1\Properties\AssemblyInfo.cs

?????文件???????3067??2014-04-25?11:26??ClassLibrary1\ClassLibrary1\shenfenService.cs

?????文件???????2345??2014-04-20?12:02??ClassLibrary1\lbj.sln

????..A..H.?????74752??2014-04-25?16:14??ClassLibrary1\lbj.suo

?????文件??????10240??2014-04-25?12:19??ClassLibrary1\lbjBLL\bin\Debug\ClassLibrary1.dll

?????文件??????26112??2014-04-25?12:19??ClassLibrary1\lbjBLL\bin\Debug\ClassLibrary1.pdb

?????文件???????9728??2014-04-25?12:19??ClassLibrary1\lbjBLL\bin\Debug\lbjBLL.dll

?????文件??????26112??2014-04-25?12:19??ClassLibrary1\lbjBLL\bin\Debug\lbjBLL.pdb

?????文件???????7680??2014-04-25?12:19??ClassLibrary1\lbjBLL\bin\Debug\lbjMod.dll

?????文件??????32256??2014-04-25?12:19??ClassLibrary1\lbjBLL\bin\Debug\lbjMod.pdb

?????文件???????1223??2014-04-25?10:39??ClassLibrary1\lbjBLL\dengjibBLL.cs

?????文件???????2249??2014-04-25?00:17??ClassLibrary1\lbjBLL\gonggaobBLL.cs

?????文件???????2146??2014-04-25?12:03??ClassLibrary1\lbjBLL\jingjaibBLL.cs

?????文件????????715??2014-04-25?12:07??ClassLibrary1\lbjBLL\jingpianbBLL.cs

............此處省略236個文件信息