【SQLServer】DBHelper即Ｃ＃数据库底层封装

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Configuration;
using System.Data.SqlClient;
using System.Data;
namespace MYHelper
{
//不加public，只有dal私有引用；
//封装执行sql server增删改查辅助类，提供相应执行sql语句和存储过程的方法
//作者：白宁超（http://www.cnblogs.com/baiboy/）
static class SQLHelper
{
//读取配置文件中的连接字符串
static string connstr = ConfigurationManager.ConnectionStrings["sql"].ConnectionString;
/// <summary>
/// 执行非查询sql语句，返回受影响行数，如果执行非增删改则返回-1
/// </summary>
/// <param name="sql">sql语句</param>
/// <param name="paras">参数数组</param>
/// <returns>影响行数res</returns>
public static int ExecuteNonQuery(string sql, params SqlParameter[] paras)
{
int res = -1;
using (SqlConnection conn = new SqlConnection(connstr))
{
using (SqlCommand cmd = new SqlCommand(sql, conn))
{
cmd.CommandType = CommandType.StoredProcedure;
if (paras != null || paras.Length > 0)
{
cmd.Parameters.AddRange(paras);
}
conn.Open();
res = cmd.ExecuteNonQuery();
}
}
return res;
}
/// <summary>
/// 执行非查询sql语句，返回受影响行数，如果执行非增删改则返回-1
/// </summary>
/// <param name="sql">sql语句</param>
/// <param name="paras">参数数组</param>
/// <returns>影响行数res</returns>
public static int ExecuteNonParaQuery(string sql)
{
int res = -1;
using (SqlConnection conn = new SqlConnection(connstr))
{
using (SqlCommand cmd = new SqlCommand(sql, conn))
{
conn.Open();
res = cmd.ExecuteNonQuery();
}
}
return res;
}
/// <summary>
/// 执行读取数据，返回一个对象
/// </summary>
/// <param name="sql">sql语句</param>
/// <param name="paras">参数数组</param>
/// <returns>返回一个对象o</returns>
public static object ExecuteScalar(string sql, params SqlParameter[] paras)
{
object  o = null;
using (SqlConnection conn = new SqlConnection(connstr))
{
using (SqlCommand cmd = new SqlCommand(sql, conn))
{
cmd.CommandType = CommandType.StoredProcedure;
if (paras != null)
{
cmd.Parameters.AddRange(paras);
}
conn.Open();
o = cmd.ExecuteScalar();
}
}
return o;
}
/// <summary>
/// 执行查询sql语句，返回一个对象
/// </summary>
/// <param name="sql">sql语句</param>
/// <param name="paras">查询参数</param>
/// <returns>返回DataReader对象</returns>
public static SqlDataReader ExecuteReader(string sql, params SqlParameter[] paras)
{
SqlConnection conn = new SqlConnection(connstr);
using (SqlCommand cmd = new SqlCommand(sql, conn))
{
cmd.CommandType = CommandType.StoredProcedure;
if (paras != null)
{
cmd.Parameters.AddRange(paras);
}
conn.Open();
try
{
return cmd.ExecuteReader(CommandBehavior.CloseConnection);
}
catch (Exception ex)
{
cmd.Dispose();
throw ex;
}
}
}

/// <summary>
/// 执行查询sql语句，返回一个无参数dataset对象
/// </summary>
/// <param name="sql">sql语句</param>
/// <param name="paras"></param>
/// <returns>返回dataset 对象</returns>
public static DataSet GetDataSetNotPara(string sql)
{
DataSet ds = new DataSet();
using (SqlConnection conn = new SqlConnection(connstr))
{
using (SqlCommand cmd = new SqlCommand(sql, conn))
{
//根据传来的参数。决定是sql语句还是存储过程
cmd.CommandType = CommandType.StoredProcedure;
conn.Open();
using (SqlDataAdapter sda = new SqlDataAdapter(cmd))
{
sda.Fill(ds);
}
}
}
return ds;
}

/// <summary>
/// 执行查询sql语句，返回一个无参数dataset对象
/// </summary>
/// <param name="sql">sql语句</param>
/// <param name="paras"></param>
/// <returns>返回dataset 对象</returns>
public static DataTable  GetDataTableNotPara(string sql)
{
DataTable dt = new DataTable();
using (SqlConnection conn = new SqlConnection(connstr))
{
using (SqlCommand cmd = new SqlCommand(sql, conn))
{
//根据传来的参数。决定是sql语句还是存储过程

conn.Open();
using (SqlDataAdapter sda = new SqlDataAdapter(cmd))
{
sda.Fill(dt);
}
}
}
return dt;
}

/// <summary>
/// 执行查询sql语句，返回一个dataset对象
/// </summary>
/// <param name="sql">sql语句</param>
/// <param name="paras">查询参数</param>
/// <returns>返回dataset 对象</returns>
public static DataSet GetDataSet(string sql, params SqlParameter[] paras)
{
DataSet  ds = new DataSet();
using (SqlConnection conn = new SqlConnection(connstr))
{
using (SqlCommand cmd = new SqlCommand(sql, conn))
{
//根据传来的参数。决定是sql语句还是存储过程
cmd.CommandType = CommandType.StoredProcedure;
//添加参数
cmd.Parameters.AddRange(paras);
conn.Open();
using (SqlDataAdapter sda = new SqlDataAdapter(cmd))
{
sda.Fill(ds);
}
}
}
return ds;
}
/// <summary>
/// 可以执行sql语句或存储过程
/// </summary>
/// <param name="text"></param>
/// <param name="ct"></param>
/// <param name="param"></param>
/// <returns></returns>
public static DataTable ProcGetTable(string sql, params SqlParameter[] param)
{
DataTable dt = new DataTable();

using (SqlConnection conn = new SqlConnection(connstr))
{
using (SqlCommand cmd = new SqlCommand(sql, conn))
{
//根据传来的参数。决定是sql语句还是存储过程

cmd.CommandType = CommandType.StoredProcedure;
//添加参数
cmd.Parameters.AddRange(param);
//cmd.Parameters.Add("@name", SqlDbType.NVarChar, 20).Value = param[0];
//cmd.Parameters.Add("@pwd", SqlDbType.NVarChar, 20).Value = param[1];
conn.Open();
using (SqlDataAdapter sda = new SqlDataAdapter(cmd))
{
sda.Fill(dt);
}
}
}
return dt;
}

/// <summary>
/// 实现分页功能
/// </summary>
/// <param name="sql">sql语句</param>
/// <param name="paras">参数数组（显示index页和每页显示条数size）</param>
/// <returns>查询结果</returns>
public static DataTable GetParaTable(string sql, params SqlParameter[] paras)
{
DataSet ds = new DataSet();
using (SqlConnection conn = new SqlConnection(connstr))
{
using (SqlDataAdapter da = new SqlDataAdapter(sql, conn))
{
if (paras != null)
{
da.SelectCommand.Parameters.AddRange(paras);
}
da.SelectCommand.CommandType = CommandType.StoredProcedure;
da.Fill(ds);
}
}
return ds.Tables[0];
}
}
}