classsqlcaozuo.cs

超市进销存管理系统 Visual Studio 2005+SQL Sever2005

using System;
using System.Collections.Generic;
using System.IO;
using System.Text;
using System.Data;
using System.Data.SqlClient;
using System.Windows.Forms;

namespace _10901BS
{
     public partial class SqlCaoZuo
    {
         
         
        /// <summary>
        /// 代码中用到的变量
        /// </summary> 
        
        //txt文件用变量
        
        StreamReader smRd;

        //数据库用变量
        SqlConnection con;
        SqlCommand com;
        public SqlDataAdapter da;
        SqlCommandBuilder scb;
        DataSet ds;
        string conStr;
        
        /// <summary>
        /// 构造函数
        /// </summary>
        public SqlCaoZuo()
        {
        }

        /// <summary>
        /// 连接数据库
        /// </summary>
        /// <returns>SqlConnection</returns>
        public SqlConnection sqlCon()
        {
            try
            {
                //txt文件读取
               
                smRd = new StreamReader(@"..\..\Resources\sqlConStr.txt");
                conStr = smRd.ReadLine();
                smRd.Close();


                //连接数据库
                con = new SqlConnection(conStr);
                con.Open();
                
                return con;
            }
            catch (Exception ex)
            {
                MessageBox.Show("错误：" + ex, "错误提示", MessageBoxButtons.OKCancel, MessageBoxIcon.Error);
                return con;
            }            

        }

        /// <summary>
        /// 执行SQL语句
        /// </summary>
        /// <param name="comStr">要执行的SQL语句</param>
        /// <returns>bool</returns>
        public bool sqlCom(string comStr)
        {
            com = new SqlCommand(comStr, sqlCon());
            try
            {
                com.ExecuteNonQuery();
                return true;
            }
            catch (Exception ex)
            {
                MessageBox.Show("错误：" + ex, "错误提示", MessageBoxButtons.OKCancel, MessageBoxIcon.Error);
                return false;
            }
            finally
            {
                if (sqlCon().State == ConnectionState.Open)
                {
                    sqlCon().Close();
                    sqlCon().Dispose();
                }
            }
        }

        /// <summary>
        /// 返回单个单元格的值
        /// </summary>
        /// <param name="comStr">要执行的SQL语句</param>
        /// <returns>string</returns>
        public string sqlComCell(string comStr)
        {
            com = new SqlCommand(comStr, sqlCon());
            try
            {                
                return com.ExecuteScalar().ToString();
            }
            catch (Exception ex)
            {
                MessageBox.Show("错误：" + ex, "错误提示", MessageBoxButtons.OKCancel, MessageBoxIcon.Error);
                return null;
            }
            finally
            {
                if (sqlCon().State == ConnectionState.Open)
                {
                    sqlCon().Close();
                    sqlCon().Dispose();
                }
            }
        }

        /// <summary>
        /// 返回数据集类型
        /// </summary>
        /// <param name="comStr">要查询的SQL语句</param>
        /// <returns>DataSet</returns>
         public DataSet dsShuJuJi(string comStr)
        {
            try
            {
                da = new SqlDataAdapter(comStr, sqlCon());
                scb = new SqlCommandBuilder(da);
                ds = new DataSet();
                da.Fill(ds);
                
                return ds;
            }
            catch (Exception ex)
            {
                MessageBox.Show("错误：" + ex, "错误提示", MessageBoxButtons.OKCancel, MessageBoxIcon.Error);
                return null;
            }
            finally
            {
                if (sqlCon().State == ConnectionState.Open)
                {
                    sqlCon().Close();
                    sqlCon().Dispose();
                }
            }
        }

        /// <summary>
        /// 返回数据表类型
        /// </summary>
        /// <param name="comStr">要查询的SQL语句</param>        
        /// <returns>DataTable</returns>
         public DataTable dtShuJuBiao(string comStr)
        {
            DataTable dt;
            try
            {
                da = new SqlDataAdapter(comStr, sqlCon());
                scb = new SqlCommandBuilder(da);
                dt = new DataTable();
                da.Fill(dt);
                return dt;
            }
            catch (Exception ex)
            {
                MessageBox.Show("错误：" + ex, "错误提示", MessageBoxButtons.OKCancel, MessageBoxIcon.Error);
                return null;
            }
            finally
            {
                if (sqlCon().State == ConnectionState.Open)
                {
                    sqlCon().Close();
                    sqlCon().Dispose();
                }
            }
        }

        /// <summary>
        /// 返回SqlDataReader类型数据
        /// </summary>
        /// <param name="comStr">要执行的SQL语句</param>
        /// <returns>SqlDataReader</returns>
         public SqlDataReader SqlDr(string comStr)
        {
            com = new SqlCommand(comStr, sqlCon());
            SqlDataReader dr;
            try
            {
                dr = com.ExecuteReader();
                return dr;
            }
            catch (Exception ex)
            {
                MessageBox.Show("错误：" + ex, "错误提示", MessageBoxButtons.OKCancel, MessageBoxIcon.Error);
                return null;
            }
            finally
            {
                if (sqlCon().State == ConnectionState.Open)
                {
                    sqlCon().Close();
                    sqlCon().Dispose();
                }
            }
        }



    }
}