【 tulaoshi.com - 编程语言 】
                             
                            SQLHelper.cs
代码如下:
using System; 
using System.Collections.Generic; 
using System.Text; 
using System.Collections; 
using System.Data; 
using System.Data.SqlClient; 
using System.Configuration; 
namespace HelloWinForm.DBUtility 
{ 
class SQLHelper 
{ 
#region 通用方法 
// 数据连接池 
private SqlConnection con; 
/// summary 
/// 返回数据库连接字符串 
/// /summary 
/// returns/returns 
public static String GetSqlConnection() 
{ 
String conn = ConfigurationManager.AppSettings["connectionString"].ToString(); 
return conn; 
} 
#endregion 
#region 执行sql字符串 
/// summary 
/// 执行不带参数的SQL语句 
/// /summary 
/// param name="Sqlstr"/param 
/// returns/returns 
public static int ExecuteSql(String Sqlstr) 
{ 
String ConnStr = GetSqlConnection(); 
using (SqlConnection conn = new SqlConnection(ConnStr)) 
{ 
SqlCommand cmd = new SqlCommand(); 
cmd.Connection = conn; 
cmd.CommandText = Sqlstr; 
conn.Open(); 
cmd.ExecuteNonQuery(); 
conn.Close(); 
return 1; 
} 
} 
/// summary 
/// 执行带参数的SQL语句 
/// /summary 
/// param name="Sqlstr"SQL语句/param 
/// param name="param"参数对象数组/param 
/// returns/returns 
public static int ExecuteSql(String Sqlstr, SqlParameter[] param) 
{ 
String ConnStr = GetSqlConnection(); 
using (SqlConnection conn = new SqlConnection(ConnStr)) 
{ 
SqlCommand cmd = new SqlCommand(); 
cmd.Connection = conn; 
cmd.CommandText = Sqlstr; 
cmd.Parameters.AddRange(param); 
conn.Open(); 
cmd.ExecuteNonQuery(); 
conn.Close(); 
return 1; 
} 
} 
/// summary 
/// 返回DataReader 
/// /summary 
/// param name="Sqlstr"/param 
/// returns/returns 
public static SqlDataReader ExecuteReader(String Sqlstr) 
{ 
String ConnStr = GetSqlConnection(); 
SqlConnection conn = new SqlConnection(ConnStr);//返回DataReader时,是不可以用using()的 
try 
{ 
SqlCommand cmd = new SqlCommand(); 
cmd.Connection = conn; 
cmd.CommandText = Sqlstr; 
conn.Open(); 
return cmd.ExecuteReader(System.Data.CommandBehavior.CloseConnection);//关闭关联的Connection 
} 
catch //(Exception ex) 
{ 
return null; 
} 
} 
/// summary 
/// 执行SQL语句并返回数据表 
/// /summary 
/// param name="Sqlstr"SQL语句/param 
/// returns/returns 
public static DataTable ExecuteDt(String Sqlstr) 
{ 
String ConnStr = GetSqlConnection(); 
using (SqlConnection conn = new SqlConnection(ConnStr)) 
{ 
SqlDataAdapter da = new SqlDataAdapter(Sqlstr, conn); 
DataTable dt = new DataTable(); 
conn.Open(); 
da.Fill(dt); 
conn.Close(); 
return dt; 
} 
} 
/// summary 
/// 执行SQL语句并返回DataSet 
/// /summary 
/// param name="Sqlstr"SQL语句/param 
/// returns/returns 
public static DataSet ExecuteDs(String Sqlstr) 
{ 
String ConnStr = GetSqlConnection(); 
using (SqlConnection conn = new SqlConnection(ConnStr)) 
{ 
SqlDataAdapter da = new SqlDataAdapter(Sqlstr, conn); 
DataSet ds = new DataSet(); 
conn.Open(); 
da.Fill(ds); 
conn.Close(); 
return ds; 
} 
} 
#endregion 
#region 操作存储过程 
/// summary 
/// 运行存储过程(已重载) 
/// /summary 
/// param name="procName"存储过程的名字/param 
/// returns存储过程的返回值/returns 
public int RunProc(string procName) 
{ 
SqlCommand cmd = CreateCommand(procName, null); 
cmd.ExecuteNonQuery(); 
this.Close(); 
return (int)cmd.Parameters["ReturnValue"].Value; 
} 
/// summary 
/// 运行存储过程(已重载) 
/// /summary 
/// param name="procName"存储过程的名字/param 
/// param name="prams"存储过程的输入参数列表/param 
/// returns存储过程的返回值/returns 
public int RunProc(string procName, SqlParameter[] prams) 
{ 
SqlCommand cmd = CreateCommand(procName, prams); 
cmd.ExecuteNonQuery(); 
this.Close(); 
return (int)cmd.Parameters[0].Value; 
} 
/// summary 
/// 运行存储过程(已重载) 
/// /summary 
/// param name="procName"存储过程的名字/param 
/// param name="dataReader"结果集/param 
public void RunProc(string procName, out SqlDataReader dataReader) 
{ 
SqlCommand cmd = CreateCommand(procName, null); 
dataReader = cmd.ExecuteReader(System.Data.CommandBehavior.CloseConnection); 
} 
/// summary 
/// 运行存储过程(已重载) 
/// /summary 
/// param name="procName"存储过程的名字/param 
/// param name="prams"存储过程的输入参数列表/param 
/// param name="dataReader"结果集/param 
public void RunProc(string procName, SqlParameter[] prams, out SqlDataReader dataReader) 
{ 
SqlCommand cmd = CreateCommand(procName, prams); 
dataReader = cmd.ExecuteReader(System.Data.CommandBehavior.CloseConnection); 
} 
/// summary 
/// 创建Command对象用于访问存储过程 
/// /summary 
/// param name="procName"存储过程的名字/param 
/// param name="prams"存储过程的输入参数列表/param 
/// returnsCommand对象/returns 
private SqlCommand CreateCommand(string procName, SqlParameter[] prams) 
{ 
// 确定连接是打开的 
Open(); 
//command = new SqlCommand( sprocName, new SqlConnection( ConfigManager.DALConnectionString ) ); 
SqlCommand cmd = new SqlCommand(procName, con); 
cmd.CommandType = CommandType.StoredProcedure; 
// 添加存储过程的输入参数列表 
if (prams != null) 
{ 
foreach (SqlParameter parameter in prams) 
cmd.Parameters.Add(parameter); 
} 
// 返回Command对象 
return cmd; 
} 
/// summary 
/// 创建输入参数 
/// /summary 
/// param name="ParamName"参数名/param 
/// param name="DbType"参数类型/param 
/// param name="Size"参数大小/param 
/// param name="Value"参数值/param 
/// returns新参数对象/returns 
public SqlParameter MakeInParam(string ParamName, SqlDbType DbType, int Size, object Value) 
{ 
return MakeParam(ParamName, DbType, Size, ParameterDirection.Input, Value); 
} 
/// summary 
/// 创建输出参数 
/// /summary 
/// param name="ParamName"参数名/param 
/// param name="DbType"参数类型/param 
/// param name="Size"参数大小/param 
/// returns新参数对象/returns 
public SqlParameter MakeOutParam(string ParamName, SqlDbType DbType, int Size) 
{ 
return MakeParam(ParamName, DbType, Size, ParameterDirection.Output, null); 
} 
/// summary 
/// 创建存储过程参数 
/// /summary 
/// param name="ParamName"参数名/param 
/// param name="DbType"参数类型/param 
/// param name="Size"参数大小/param 
/// param name="Direction"参数的方向(输入/输出)/param 
/// param name="Value"参数值/param 
/// returns新参数对象/returns 
public SqlParameter MakeParam(string ParamName, SqlDbType DbType, Int32 Size, ParameterDirection Direction, object Value) 
{ 
SqlParameter param; 
if (Size  0) 
{ 
param = new SqlParameter(ParamName, DbType, Size); 
} 
else 
{ 
param = new SqlParameter(ParamName, DbType); 
} 
param.Direction = Direction; 
if (!(Direction == ParameterDirection.Output && Value == null)) 
{ 
param.Value = Value; 
} 
return param; 
} 
#endregion 
#region 数据库连接和关闭 
/// summary 
/// 打开连接池 
/// /summary 
private void Open() 
{ 
// 打开连接池 
if (con == null) 
{ 
//这里不仅需要using System.Configuration;还要在引用目录里添加 
con = new SqlConnection(GetSqlConnection()); 
con.Open(); 
} 
} 
/// summary 
/// 关闭连接池 
/// /summary 
public void Close() 
{ 
if (con != null) 
con.Close(); 
} 
/// summary 
/// 释放连接池 
/// /summary 
public void Dispose() 
{ 
// 确定连接已关闭 
if (con != null) 
{ 
con.Dispose(); 
con = null; 
} 
} 
#endregion 
} 
}
简单用一下:
代码如下:
using System; 
using System.Collections.Generic; 
using System.Text; 
using System.Data; 
using System.Data.SqlClient; 
using System.Collections; 
using HelloWinForm.DBUtility; 
namespace HelloWinForm.DAL 
{ 
class Student 
{ 
public string test() 
{ 
string str = ""; 
SqlDataReader dr = SQLHelper.ExecuteReader("select * from Student"); 
while (dr.Read()) 
{ 
str += dr["StudentNO"].ToString(); 
} 
dr.Close(); 
return str; 
} 
} 
}