public class Helper
{
private static string cons = "server=.;uid=sa;pwd=;database=pubs";
//查询
public static DataTable ExecuteDataQuery(string sql)
{
using (SqlConnection con = new SqlConnection(cons))
{
con.Open();
DataTable tbl = new DataTable();
SqlDataAdapter adap = new SqlDataAdapter(sql, con);
adap.Fill(tbl);
return tbl;
}
}
public static SqlDataReader ExecuteDataQuery(string sql)
{
SqlConnection con = new SqlConnection(cons);
SqlCommand cmd = new SqlCommand(sql, con);
con.Open();
return cmd.ExecuteReader(CommandBehavior.CloseConnection);
}
//增删改
public static void ExecuteNonQuery(string sql)
{
using (SqlConnection con = new SqlConnection(cons))
{
con.Open();
SqlCommand cmd = new SqlCommand(sql, con);
cmd.ExecuteNonQuery();
}
}
}
------------------------------------------------------------------------------------------------------------------------------
using System;
using System.Collections;
using System.Collections.Specialized;
using System.Data;
using System.Data.SqlClient;
using System.Configuration;
/// <summary>
/// Copyright (C) 2004-2008 LiTianPing
/// 数据访问基础类(基于SQLServer)
/// 用户可以修改满足自己项目的需要。
/// </summary>
public abstract class DbHelperSQL
{
protected static string connectionString = CFunc.ConnectionString;
public static SqlConnection conn = null;
public static void connColse()
{
if (conn.State == ConnectionState.Open)
{
conn.Close();
}
}
#region 执行简单SQL语句
/// <summary>
/// 执行SQL语句，返回影响的记录数
/// </summary>
/// <param name="SQLString">SQL语句</param>
/// <returns>影响的记录数</returns>
public static int ExecuteSql(string SQLString)
{
conn = new SqlConnection(connectionString);
using (SqlCommand cmd = new SqlCommand(SQLString, conn))
{
try
{
conn.Open();
int rows = cmd.ExecuteNonQuery();
return rows;
}
catch (System.Data.SqlClient.SqlException E)
{
throw new Exception(E.Message);
}
finally
{
cmd.Dispose();
conn.Close();
}
}
}
/// <summary>
/// 执行多条SQL语句，实现数据库事务。
/// </summary>
/// <param name="SQLStringList">多条SQL语句</param>
public static void ExecuteSqlTran(ArrayList SQLStringList)
{
conn = new SqlConnection(connectionString);
conn.Open();
SqlCommand cmd = new SqlCommand();
cmd.Connection = conn;
SqlTransaction tx = conn.BeginTransaction();
cmd.Transaction = tx;
try
{
for (int n = 0; n < SQLStringList.Count; n++)
{
string strsql = SQLStringList[n].ToString();
if (strsql.Trim().Length > 1)
{
cmd.CommandText = strsql;
cmd.ExecuteNonQuery();
}
}
tx.Commit();
}
catch (System.Data.SqlClient.SqlException E)
{
tx.Rollback();
throw new Exception(E.Message);
}
finally
{
cmd.Dispose();
conn.Close();
}
}
/// <summary>
/// 执行带一个存储过程参数的的SQL语句。
/// </summary>
/// <param name="SQLString">SQL语句</param>
/// <param name="content">参数内容,比如一个字段是格式复杂的文章，有特
殊符号，可以通过这个方式添加</param>
/// <returns>影响的记录数</returns>
public static int ExecuteSql(string SQLString, string content)
{
conn = new SqlConnection(connectionString);
SqlCommand cmd = new SqlCommand(SQLString, conn);
System.Data.SqlClient.SqlParameter myParameter = new
System.Data.SqlClient.SqlParameter("@content", SqlDbType.NText);
myParameter.Value = content;
cmd.Parameters.Add(myParameter);
try
{
conn.Open();
int rows = cmd.ExecuteNonQuery();
return rows;
}
catch (System.Data.SqlClient.SqlException E)
{
throw new Exception(E.Message);
}
finally
{
cmd.Dispose();
conn.Close();
}
}
/// <summary>
/// 向数据库里插入图像格式的字段(和上面情况类似的另一种实例)
/// </summary>
/// <param name="strSQL">SQL语句</param>
/// <param name="fs">图像字节,数据库的字段类型为image的情况</param>
/// <returns>影响的记录数</returns>
public static int ExecuteSqlInsertImg(string strSQL, byte[] fs)
{
conn = new SqlConnection(connectionString);
SqlCommand cmd = new SqlCommand(strSQL, conn);
System.Data.SqlClient.SqlParameter myParameter = new
System.Data.SqlClient.SqlParameter("@fs", SqlDbType.Image);
myParameter.Value = fs;
cmd.Parameters.Add(myParameter);
try
{
conn.Open();
int rows = cmd.ExecuteNonQuery();
return rows;
}
catch (System.Data.SqlClient.SqlException E)
{
throw new Exception(E.Message);
}
finally
{
cmd.Dispose();
conn.Close();
}
}
/// <summary>
/// 执行一条计算查询结果语句，返回查询结果（object）。
/// </summary>
/// <param name="SQLString">计算查询结果语句</param>
/// <returns>查询结果（object）</returns>
public static object GetSingle(string SQLString)
{
conn = new SqlConnection(connectionString);
using (SqlCommand cmd = new SqlCommand(SQLString, conn))
{
try
{
conn.Open();
object obj = cmd.ExecuteScalar();
if ((Object.Equals(obj, null)) || (Object.Equals(obj,
System.DBNull.Value)))
{
return null;
}
else
{
return obj;
}
}
catch (System.Data.SqlClient.SqlException e)
{
conn.Close();
throw new Exception(e.Message);
}
finally
{
cmd.Dispose();
conn.Close();
}
}
}
/// <summary>
/// 执行查询语句，返回SqlDataReader
/// </summary>
/// <param name="strSQL">查询语句</param>
/// <returns>SqlDataReader</returns>
public static SqlDataReader ExecuteReader(string strSQL)
{//使用完后请关闭conn
conn = new SqlConnection(connectionString);
SqlCommand cmd = new SqlCommand(strSQL, conn);
try
{
conn.Open();
SqlDataReader myReader = cmd.ExecuteReader();
return myReader;
}
catch (System.Data.SqlClient.SqlException e)
{
throw new Exception(e.Message);
}
}