数据访问类SqlClient

using System;using System.ComponentModel;using System.Collections;using System.Diagnostics;using System.Data;using System.Data.SqlClient;using System.Configuration;using Microsoft.Win32;using System.IO;using System.Windows.Forms;namespace Sun.WebExam{ public class DB : IDisposable  {  // 连接数据源

  private SqlConnection con;    /// <summary>  /// 执行存储过程  /// </summary>  /// <param name="procName">存储过程的名称</param>  /// <returns>返回存储过程返回值</returns>  public int RunProc(string procName)   {   SqlCommand cmd = CreateCommand(procName, null);   cmd.ExecuteNonQuery();   this.Close();   return (int)cmd.Parameters["ReturnValue"].Value;  }

  

  /// <summary>  /// 执行存储过程  /// </summary>  /// <param name="procName">存储过程名称</param>  /// <param name="prams">存储过程所需参数</param>  /// <returns>返回存储过程返回值</returns>  public int RunProc(string procName, SqlParameter[] prams)   {   SqlCommand cmd = CreateCommand(procName, prams);   cmd.ExecuteNonQuery();   this.Close();   return (int)cmd.Parameters["ReturnValue"].Value;  }

  /// <summary>  /// 执行存储过程  /// </summary>  /// <param name="procName">存储过程的名称</param>  /// <param name="dataReader">返回存储过程返回值</param>  public void RunProc(string procName, out SqlDataReader dataReader)   {   SqlCommand cmd = CreateCommand(procName, null);   dataReader = cmd.ExecuteReader(System.Data.CommandBehavior.CloseConnection);   //return (int)cmd.Parameters["ReturnValue"].Value;  }

  /// <summary>  /// 执行存储过程  /// </summary>  /// <param name="procName">存储过程的名称</param>  /// <param name="prams">存储过程所需参数</param>  /// <param name="dataReader">存储过程所需参数</param>  public void RunProc(string procName, SqlParameter[] prams, out SqlDataReader dataReader)   {   SqlCommand cmd = CreateCommand(procName, prams);   dataReader = cmd.ExecuteReader(System.Data.CommandBehavior.CloseConnection);   //return (int)cmd.Parameters["ReturnValue"].Value;  }    /// <summary>  /// 创建一个SqlCommand对象以此来执行存储过程  /// </summary>  /// <param name="procName">存储过程的名称</param>  /// <param name="prams">存储过程所需参数</param>  /// <returns>返回SqlCommand对象</returns>  private SqlCommand CreateCommand(string procName, SqlParameter[] prams)   {   // 确认打开连接   Open();

      SqlCommand cmd = new SqlCommand(procName, con);   cmd.CommandType = CommandType.StoredProcedure;

   // 依次把参数传入存储过程   if (prams != null)    {    foreach (SqlParameter parameter in prams)     cmd.Parameters.Add(parameter);   }      // 加入返回参数   cmd.Parameters.Add(    new SqlParameter("ReturnValue", SqlDbType.Int, 4,    ParameterDirection.ReturnValue, false, 0, 0,    string.Empty, DataRowVersion.Default, null));

   return cmd;  }

  /// <summary>  /// 执行一条不需要返回值SQL命令，比如插入、删除  /// </summary>  /// <param name="commtext"></param>  public void ExecCommand(string commtext)   {   Open();

   SqlCommand cmd = new SqlCommand(commtext,con);   cmd.CommandType = CommandType.Text;   cmd.ExecuteNonQuery();   cmd.Dispose();  }

  /// <summary>  /// 执行多条不需要返回值SQL命令，比如插入、删除  /// </summary>  /// <param name="commtext">多条SQL语句</param>  public void ExecCommand(string[] commtext)   {   Open();

   for(int i=0;i<commtext.Length;i++)   {    SqlCommand cmd = new SqlCommand(commtext[i],con);    cmd.CommandType = CommandType.Text;    cmd.ExecuteNonQuery();    cmd.Dispose();   }  }

  /// <summary>  /// 执行一条不需要返回值SQL命令，比如插入、删除，可以带一个参数数组  /// </summary>  /// <param name="commtext"></param>  /// <param name="prams"></param>  public void ExecCommand(string commtext,SqlParameter[] prams)   {   Open();

   SqlCommand cmd = new SqlCommand(commtext,con);   cmd.CommandType = CommandType.Text;

   if (prams != null)    {    foreach (SqlParameter parameter in prams)     cmd.Parameters.Add(parameter);   }

   cmd.ExecuteNonQuery();   cmd.Dispose();   con.Close();  }

  /// <summary>  /// 执行一条SQL语句，把图片保存到数据库  /// </summary>  /// <param name="commtext">sql语句</param>  /// <param name="content">byte[]</param>//  public void ExecCommand(string commtext,byte[] content)//  {//   Open();//   SqlCommand cmd=new SqlCommand(commtext,con);//   cmd.CommandType=CommandType.Text;//   cmd.Parameters.Add("@pic",SqlDbType.Image).Value=content;//   cmd.ExecuteNonQuery();//   cmd.Dispose();//  }

  /// <summary>  /// 执行一条SQL语句，把DataSet中的字段（图片）保存到数据库  /// </summary>  /// <param name="commtext"></param>  /// <param name="content"></param>  public void ExecCommand(string commtext,object content)  {   Open();   SqlCommand cmd=new SqlCommand(commtext,con);   cmd.CommandType=CommandType.Text;   cmd.Parameters.Add("@pic",content);   cmd.ExecuteNonQuery();   cmd.Dispose();  }

    /// <summary>  /// 执行一条统计类的SQL语句，返回一个整数  /// </summary>  /// <param name="CommText"></param>  /// <returns></returns>  public int ExecScalar(string CommText)  {   Open();

   SqlCommand  cmd=new SqlCommand(CommText,con);   cmd.CommandType=CommandType.Text;   return cmd.ExecuteScalar()!=null?(int)cmd.ExecuteScalar():0;  }

  /// <summary>  /// 执行一条统计类的SQL语句，返回一个整数。可以带参数数字  /// </summary>  /// <param name="CommText"></param>  /// <param name="prams"></param>  /// <returns></returns>  public int ExecScalar(string CommText,SqlParameter[] prams)  {   Open();

   SqlCommand  cmd=new SqlCommand(CommText,con);   cmd.CommandType=CommandType.Text;

   if (prams != null)    {    foreach (SqlParameter parameter in prams)     cmd.Parameters.Add(parameter);   }

   return cmd.ExecuteScalar()!=null?(int)cmd.ExecuteScalar():0;  }

  /// <summary>  /// 查询最大值  /// </summary>  /// <param name="CommText"></param>  /// <returns></returns>  public string SelectMax(string CommText)  {   Open();

   SqlCommand  cmd=new SqlCommand(CommText,con);   cmd.CommandType=CommandType.Text;   return cmd.ExecuteScalar().ToString();  }

  /// <summary>  /// 执行一条查询语句，并将查询结果返回为一个数据读器；  /// </summary>  /// <param name="commtext"></param>  /// <param name="dr"></param>  public void ExecQuery(string commtext,out SqlDataReader dr)  {   Open();   SqlCommand cmd = new SqlCommand(commtext,con);   cmd.CommandType = CommandType.Text;

   dr=cmd.ExecuteReader(System.Data.CommandBehavior.CloseConnection);   cmd.Dispose();

  }

  /// <summary>  /// 打开数据库连接.  /// </summary>  private void Open()   {   // 打开数据库连接   if (con == null)    {

//    RegistryKey rk=Registry.LocalMachine;//    RegistryKey subrk=rk.OpenSubKey("software//Sunsoft//SunCdas");//    string connString=(string)subrk.GetValue("server");    string connString="workstation id=xxx;packet size=4096;user id=sa;pwd=;data source=syringa;persist security info=False;initial catalog=SunWebExam";    con = new SqlConnection(connString);    con.Open();   }       if(con.State ==System.Data.ConnectionState.Closed)    con.Open();

  }

  /// <summary>  /// 关闭数据库连接  /// </summary>  public void Close()   {   if (con != null)    con.Close();  }

  /// <summary>  /// 释放资源  /// </summary>  public void Dispose()   {   // 确认连接是否已经关闭   if (con != null)    {    con.Dispose();    con = null;   }      }

  /// <summary>  /// 传入输入参数  /// </summary>  /// <param name="ParamName">存储过程名称</param>  /// <param name="DbType">参数类型</param></param>  /// <param name="Size">参数大小</param>  /// <param name="Value">参数值</param>  /// <returns>新的 parameter 对象</returns>  public SqlParameter MakeInParam(string ParamName, SqlDbType DbType, int Size, object Value)   {   return MakeParam(ParamName, DbType, Size, ParameterDirection.Input, Value);  }  

  /// <summary>  /// 传入返回值参数  /// </summary>  /// <param name="ParamName">存储过程名称</param>  /// <param name="DbType">参数类型</param>  /// <param name="Size">参数大小</param>  /// <returns>新的 parameter 对象</returns>  public SqlParameter MakeOutParam(string ParamName, SqlDbType DbType, int Size)   {   return MakeParam(ParamName, DbType, Size, ParameterDirection.Output, null);  }  

  /// <summary>  /// 传入返回值参数  /// </summary>  /// <param name="ParamName">存储过程名称</param>  /// <param name="DbType">参数类型</param>  /// <param name="Size">参数大小</param>  /// <returns>新的 parameter 对象</returns>  public SqlParameter MakeReturnParam(string ParamName, SqlDbType DbType, int Size)   {   return MakeParam(ParamName, DbType, Size, ParameterDirection.ReturnValue, null);  }    /// <summary>  /// 生成存储过程参数  /// </summary>  /// <param name="ParamName">存储过程名称</param>  /// <param name="DbType">参数类型</param>  /// <param name="Size">参数大小</param>  /// <param name="Direction">参数方向</param>  /// <param name="Value">参数值</param>  /// <returns>新的 parameter 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;  }

  /// <summary>  /// 执行一条SQL语句，并返回一个命名了数据表的数据集  /// </summary>  /// <param name="cmdtext">SQL语句</param>  /// <param name="tablename">表名</param>  /// <param name="ds">数据集</param>  public void Exec4DS(string CmdText,string TableName,out DataSet DS)  {       Open();    DS=new DataSet();    SqlDataAdapter da=new SqlDataAdapter(CmdText,con);   try   {     da.Fill(DS,TableName);   }   catch(Exception ex)   {    MessageBox.Show(ex.ToString());   }  }

  /// <summary>  ///  执行一条带参数的SQL语句，并返回一个命名了数据表的数据集  /// </summary>  /// <param name="cmdtext">SQL语句</param>  /// <param name="tablename">表名</param>  /// <param name="prams">参数数组</param>  /// <param name="ds">数据集</param>  public void Exec4DS(string cmdtext,string tablename,SqlParameter[] prams,out DataSet ds)  {   Open();   ds=new DataSet();   SqlCommand cmd = new SqlCommand(cmdtext, con);   cmd.CommandType = CommandType.Text;   if (prams != null)    {    foreach (SqlParameter parameter in prams)     cmd.Parameters.Add(parameter);   }   SqlDataAdapter da=new SqlDataAdapter(cmd);   da.Fill(ds,tablename);  }

  /// <summary>  /// 一次执行多条SQL语句，将多个表填入一个DataSet  /// </summary>  /// <param name="sqlCmds">SQL语句数组</param>  /// <param name="TableNames">表名数组</param>  /// <param name="DS">数据集名</param>  public void ExecXDS(string[] sqlCmds,string[] TableNames,out DataSet DS)  {   Open();   DS=new DataSet();   for(int i=0;i<sqlCmds.Length;i++)   {    SqlDataAdapter da=new SqlDataAdapter(sqlCmds[i],con);    da.Fill(DS,TableNames[i]);   }  }

 }}