using System;using System.Collections.Generic;using System.ComponentModel;using System.Data;using System.Drawing;using System.Linq;using System.Text;using System.Windows.Forms;using System.Data.SqlClient;using System.IO;namespace CollectionEnginery{  public partial class Form1 : Form  {    public Form1()    {      InitializeComponent();    }    public static SqlConnection My_con; //定義一個SqlConnection類型的公共變量My_con，用于判斷數據庫是否連接成功    public static string M_str_sqlcon = "Data Source=.;Database=CollectionEnginery;User id=sa;PWD=";    StreamReader SReader;    #region 建立數據庫連接    /// <summary>    /// 建立數據庫連接.    /// </summary>    /// <returns>返回SqlConnection對象</returns>    public static SqlConnection getcon()    {      My_con = new SqlConnection(M_str_sqlcon);  //用SqlConnection對象與指定的數據庫相連接      My_con.Open(); //打開數據庫連接      return My_con; //返回SqlConnection對象的信息    }    #endregion    #region 創建DataSet對象    /// <summary>    /// 創建一個DataSet對象    /// </summary>    /// <param name="M_str_sqlstr">SQL語句</param>    /// <param name="M_str_table">表名</param>    /// <returns>返回DataSet對象</returns>    public DataSet getDataSet(string SQLstr, string tableName)    {      getcon();  //打開與數據庫的連接      SqlDataAdapter SQLda = new SqlDataAdapter(SQLstr, My_con); //創建一個SqlDataAdapter對象，并獲取指定數據表的信息      DataSet My_DataSet = new DataSet(); //創建DataSet對象      SQLda.Fill(My_DataSet, tableName); //通過SqlDataAdapter對象的Fill()方法，將數據表信息添加到DataSet對象中      con_close();  //關閉數據庫的連接      return My_DataSet; //返回DataSet對象的信息    }    #endregion    #region 關閉數據庫連接    /// <summary>    /// 關閉于數據庫的連接.    /// </summary>    public void con_close()    {      if (My_con.State == ConnectionState.Open)  //判斷是否打開與數據庫的連接      {        My_con.Close();  //關閉數據庫的連接        My_con.Dispose();  //釋放My_con變量的所有空間      }    }    #endregion    private void Form1_Load(object sender, EventArgs e)    {      DataSet dataSet = new DataSet();      dataSet = getDataSet("select * from tb_Collection", "tb_Collection");      dataGridView1.DataSource = dataSet.Tables[0];      dataGridView1.Columns[0].HeaderText = "編號";      dataGridView1.Columns[0].Width = 40;      dataGridView1.Columns[1].HeaderText = "書名";      dataGridView1.Columns[1].Width = 140;      dataGridView1.Columns[2].HeaderText = "條形碼";      dataGridView1.Columns[2].Width = 80;      dataGridView1.Columns[3].HeaderText = "累加值";      dataGridView1.Columns[3].Width = 80;      dataGridView1.Columns[4].HeaderText = "總計";      dataGridView1.Columns[4].Width = 40;    }    private void button1_Click(object sender, EventArgs e)    {      string tem_str = "";//記錄當前行      string tem_code = "";//條形碼號      string tem_mark = "";//個數      string tem_s=" ";      StreamReader var_SRead = new StreamReader(Application.StartupPath + "http://AddData.dat");//實例化StreamReader，并打開指定的文件      while (true)//讀取dat文件中的所有行      {        tem_str = var_SRead.ReadLine();//記錄dat文件指定行的數據        tem_code = tem_str.Substring(0, tem_str.IndexOf(Convert.ToChar(tem_s))).Trim();//獲取當前行的條形碼        tem_mark = tem_str.Substring(tem_str.IndexOf(Convert.ToChar(tem_s)), tem_str.Length - tem_str.IndexOf(Convert.ToChar(tem_s))-1).Trim();//獲取當前條形碼的個數        for (int i = 0; i < dataGridView1.RowCount - 1; i++)//在dataGridView1控件中查找相應的條形碼        {          if (dataGridView1.Rows[i].Cells[2].Value.ToString().Trim() == tem_code)//如查找到          {            dataGridView1.Rows[i].Cells[3].Value = tem_mark.ToString();//顯示當前要添加的個數            dataGridView1.Rows[i].Cells[4].Value = Convert.ToInt32(dataGridView1.Rows[i].Cells[4].Value) + Convert.ToInt32(tem_mark);//計算當前條形碼的總數          }        }        if (var_SRead.EndOfStream)//如果查詢到文件尾          break;//退出循環      }      var_SRead.Close();//釋放所有資源    }  }}