C#结合数据库的数据采集器示例

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; //定义一个SqlConnection类型的公共变量My_con，用于判断数据库是否连接成功    public static string M_str_sqlcon = "Data Source=.;Database=CollectionEnginery;User id=sa;PWD=";    StreamReader SReader;    #region 建立数据库连接    /// <summary>    /// 建立数据库连接.    /// </summary>    /// <returns>返回SqlConnection对象</returns>    public static SqlConnection getcon()    {      My_con = new SqlConnection(M_str_sqlcon);  //用SqlConnection对象与指定的数据库相连接      My_con.Open(); //打开数据库连接      return My_con; //返回SqlConnection对象的信息    }    #endregion    #region 创建DataSet对象    /// <summary>    /// 创建一个DataSet对象    /// </summary>    /// <param name="M_str_sqlstr">SQL语句</param>    /// <param name="M_str_table">表名</param>    /// <returns>返回DataSet对象</returns>    public DataSet getDataSet(string SQLstr, string tableName)    {      getcon();  //打开与数据库的连接      SqlDataAdapter SQLda = new SqlDataAdapter(SQLstr, My_con); //创建一个SqlDataAdapter对象，并获取指定数据表的信息      DataSet My_DataSet = new DataSet(); //创建DataSet对象      SQLda.Fill(My_DataSet, tableName); //通过SqlDataAdapter对象的Fill()方法，将数据表信息添加到DataSet对象中      con_close();  //关闭数据库的连接      return My_DataSet; //返回DataSet对象的信息    }    #endregion    #region 关闭数据库连接    /// <summary>    /// 关闭于数据库的连接.    /// </summary>    public void con_close()    {      if (My_con.State == ConnectionState.Open)  //判断是否打开与数据库的连接      {        My_con.Close();  //关闭数据库的连接        My_con.Dispose();  //释放My_con变量的所有空间      }    }    #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 = "编号";      dataGridView1.Columns[0].Width = 40;      dataGridView1.Columns[1].HeaderText = "书名";      dataGridView1.Columns[1].Width = 140;      dataGridView1.Columns[2].HeaderText = "条形码";      dataGridView1.Columns[2].Width = 80;      dataGridView1.Columns[3].HeaderText = "累加值";      dataGridView1.Columns[3].Width = 80;      dataGridView1.Columns[4].HeaderText = "总计";      dataGridView1.Columns[4].Width = 40;    }    private void button1_Click(object sender, EventArgs e)    {      string tem_str = "";//记录当前行      string tem_code = "";//条形码号      string tem_mark = "";//个数      string tem_s=" ";      StreamReader var_SRead = new StreamReader(Application.StartupPath + "//AddData.dat");//实例化StreamReader，并打开指定的文件      while (true)//读取dat文件中的所有行      {        tem_str = var_SRead.ReadLine();//记录dat文件指定行的数据        tem_code = tem_str.Substring(0, tem_str.IndexOf(Convert.ToChar(tem_s))).Trim();//获取当前行的条形码        tem_mark = tem_str.Substring(tem_str.IndexOf(Convert.ToChar(tem_s)), tem_str.Length - tem_str.IndexOf(Convert.ToChar(tem_s))-1).Trim();//获取当前条形码的个数        for (int i = 0; i < dataGridView1.RowCount - 1; i++)//在dataGridView1控件中查找相应的条形码        {          if (dataGridView1.Rows[i].Cells[2].Value.ToString().Trim() == tem_code)//如查找到          {            dataGridView1.Rows[i].Cells[3].Value = tem_mark.ToString();//显示当前要添加的个数            dataGridView1.Rows[i].Cells[4].Value = Convert.ToInt32(dataGridView1.Rows[i].Cells[4].Value) + Convert.ToInt32(tem_mark);//计算当前条形码的总数          }        }        if (var_SRead.EndOfStream)//如果查询到文件尾          break;//退出循环      }      var_SRead.Close();//释放所有资源    }  }}