sql 类+连接sql server 2005-优快云博客

本文介绍了一个名为SQLHelper的类的设计与实现细节，该类用于处理SQL Server数据库的连接及基本操作，如创建连接、读取数据等，并展示了如何通过配置文件来设置数据库连接字符串。

using System;
using System.Collections.Generic;
using System.Text;
using System.Data;
using System.Data.Sql;
using System.Data.SqlClient;
using System.Configuration;
namespace misOther
{
public class SQLHelper
{
      SqlConnection cnn = null;
      SqlCommand com = new SqlCommand();

      public SqlCommand Com
      {
          get { return com; }
          set { com = value; }
      }
      public SQLHelper()
      {/////////从config取出连接字符串
        cnn=new SqlConnection(ConfigurationSettings.AppSettings["misOtherSql"]);

      }

      //打开连接
      public SqlConnection CreateCnn()
      {
          if (cnn.State == ConnectionState.Closed)
          {
              cnn.Open();
          }
          return cnn;
      }
      //关闭连接
      public void closeCnn()
      {
          if (cnn.State == ConnectionState.Open)
          {
              cnn.Close();
          }
      }
      //返回一个sqlDataReader
      public SqlDataReader sdr(string sql)
      {
          com.Connection=CreateCnn();
          com.CommandText = sql;
          SqlDataReader sdr = com.ExecuteReader();
          return sdr;

      }
      //返回一个sqlDataAdapter
      public SqlDataAdapter sda(string sql)
      {
          com.Connection = CreateCnn();
          com.CommandText = sql;
          SqlDataAdapter sda = new SqlDataAdapter(com);
          return sda;
      }
      //返回一个Dataset
      public DataSet ds(string sql, string tableName)
      {


          DataSet ds = new DataSet();
          sda(sql).Fill(ds,tableName);
          return ds;
      }
      public DataSet ds(string sql)
      {

          DataSet ds = new DataSet();
          sda(sql).Fill(ds);
          return ds;
      }
      ////format sql
      //public string FormatSql(string sql, params string[] sqlParams)
      //{   com.CommandText=sql;
      //    com.Parameters.Add(sql.

      //}
    }

}
--------------------------------------------------------------------------------------------------连接config

<?xml version="1.0" encoding="utf-8" ?>
<configuration>
<appSettings>