ADO.net常用对象演示例程

常用ADO.net对象演示

这个例程演示了OleDbConnection， OleDbCommand， cmd.Parameters， OleDbDataReader， OleDbDataAdapter， DataSet 等对象的用法。这是几天的研究成果，特此记录一下。

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.OleDb;
using System.IO;
using System.Diagnostics;

namespace WindowsFormsApplication5
{
    public partial class Form1 : Form
    {
        public Form1()
        {
            InitializeComponent();
        }

        ******* void button1_Click(object sender, EventArgs e)  //与入
        {

            OleDbConnection cn = new OleDbConnection("Provider=Microsoft.Jet.OLEDB.4.0;Data Source=" + Application.StartupPath + "\\flList.mdb" + ";Persist Security Info=True");
            cn.Open();

            OleDbCommand cmd = new OleDbCommand();
            cmd.Connection = cn;
            cmd.CommandText = "insert into list(linktxt,url,shopname,bz,banner,html) values(?,?,?,?,?,?)";
            cmd.Parameters.Add("linktxt", OleDbType.VarChar);
            cmd.Parameters["linktxt"].Value ="猪悟能的博客";
            cmd.Parameters.Add("url", OleDbType.VarChar);
            cmd.Parameters["url"].Value = "http://www.hackpig.cn";
            cmd.Parameters.Add("shopname", OleDbType.VarChar);
            cmd.Parameters["shopname"].Value = "一品香";
            cmd.Parameters.Add("bz", OleDbType.VarChar);
            cmd.Parameters["bz"].Value = "一品香";
            cmd.Parameters.Add("banner", OleDbType.VarChar);
            cmd.Parameters["banner"].Value = "banner";
            cmd.Parameters.Add("html", OleDbType.VarChar);

            FileStream fs = new FileStream(Application.StartupPath + "\\html.txt", FileMode.Open, FileAccess.Read);
            byte[] buffer=new byte[fs.Length];
            fs.Read(buffer, 0, buffer.Length);
            fs.Close();
            cmd.Parameters["html"].Value = Encoding.Default.GetString(buffer);

            cmd.Parameters.Add("babysum", OleDbType.VarChar);
            cmd.Parameters["babysum"].Value = 333;
            cmd.Parameters.Add("sellerxy", OleDbType.VarChar);
            cmd.Parameters["sellerxy"].Value = 35;
            cmd.Parameters.Add("mjxy", OleDbType.VarChar);
            cmd.Parameters["mjxy"].Value = 11;
            cmd.Parameters.Add("shopdate", OleDbType.VarChar);
            cmd.Parameters["shopdate"].Value = "1988-11-13";
            cmd.Parameters.Add("scrq", OleDbType.VarChar);
            cmd.Parameters["scrq"].Value = 41;
            cmd.Parameters.Add("service", OleDbType.VarChar);
            cmd.Parameters["service"].Value = true;
            cmd.Parameters.Add("wherefrom", OleDbType.VarChar);
            cmd.Parameters["wherefrom"].Value = "中国武汉";
            cmd.Parameters.Add("modulehtml", OleDbType.VarChar);
            cmd.Parameters["modulehtml"].Value = "modulehtml";

            cmd.ExecuteNonQuery();
            cn.Close();
        }

        p rivate void button2_Click(object sender, EventArgs e)
        {

            OleDbConnection cn = new OleDbConnection("Provider=Microsoft.Jet.OLEDB.4.0;Data Source=" + Application.StartupPath + "\\flList.mdb" + ";Persist Security Info=True");
            cn.Open();

            OleDbCommand cmd = new OleDbCommand();
            cmd.Connection = cn;
            cmd.CommandText = "select * from list";

            //OleDbDataReader数据读取器为直前只读方式
            OleDbDataReader reader = cmd.ExecuteReader();

            while (reader.Read())
            {
                //Debug.WriteLine(reader[1].ToString());
                richTextBox1.Text += reader[0].ToString();
                richTextBox1.Text += "\n";
                richTextBox1.Text += reader[1].ToString();
                richTextBox1.Text += "\n";
                richTextBox1.Text += reader[2].ToString();
                richTextBox1.Text += "\n";
                richTextBox1.Text += reader[3].ToString();
                richTextBox1.Text += "\n";

            }
            reader.Close();

        }

        p rivate void button3_Click(object sender, EventArgs e)
        { //DataBindings
            OleDbConnection cn= new OleDbConnection("Provider=Microsoft.Jet.OLEDB.4.0;Data Source=" + Application.StartupPath + "\\flList.mdb" + ";Persist Security Info=True");
            cn.Open();
            OleDbCommand cmd = new OleDbCommand();
            cmd.Connection = cn;

            OleDbDataAdapter adapter1 = new OleDbDataAdapter("select top 1 * from list",cn);
            //adapter1.SelectCommand="select * from list";
            DataSet dataSet1=new DataSet();

            adapter1.Fill(dataSet1,"list");
            textBox1.DataBindings.Add("Text", dataSet1, "list.bz");

        }

        p rivate void button4_Click(object sender, EventArgs e)
        {
            //读dataset数据
            OleDbConnection cn = new OleDbConnection("Provider=Microsoft.Jet.OLEDB.4.0;Data Source=" + Application.StartupPath + "\\flList.mdb" + ";Persist Security Info=True");
            cn.Open();
            OleDbCommand cmd = new OleDbCommand();
            cmd.Connection = cn;

            OleDbDataAdapter adapter1 = new OleDbDataAdapter("select top 1 * from list", cn);
            //adapter1.SelectCommand="select * from list";
            DataSet dataSet1 = new DataSet();

            adapter1.Fill(dataSet1, "list");
            Debug.WriteLine(dataSet1.Tables[0].Rows.Count);
            String str1=null;
            DataTable table = dataSet1.Tables[0];
            foreach (DataRow row in table.Rows)
            {
                foreach (DataColumn column in table.Columns)
                {
                    str1+=row[column];
                    //Debug.WriteLine(str1);
                    str1 += "\n";
                }
                str1 += "\n";
            }
            richTextBox1.Text = str1;

        }
    }
}