01 /*
02 * 由SharpDevelop创建。
03 * 用户： Lazynight
04 * 日期: 2011/10/30
05 * 时间: 22:38
06 *
07 * 要改变这种模板请点击 工具|选项|代码编写|编辑标准头文件
08 */
09 using System;
10 using System.Collections.Generic;
11 using System.Drawing;
12 using System.Windows.Forms;
13 using System.Data.OleDb;
14 using System.Data;
15 namespace Lazy34_动态查询数据库信息
16 {
17
18     public partial class MainForm : Form
19     {
20         OleDbConnection Lazy_con;
21         public MainForm()
22         {
23
24             InitializeComponent();
25         }
26
27         void Button1Click(object sender, EventArgs e)
28         {
29             if(comboBox1.Text==“”)
30             {
31                 MessageBox.Show(this,“艺人不能为空~请选择一位~”,“提示”,MessageBoxButtons.OK,MessageBoxIcon.Warning);
32             }
33             else
34             {
35                 string Lazy_sql=“select * from LazyData where 艺人=’”+comboBox1.SelectedItem.ToString()+“‘”;
36                 //SQL查询
37                 OleDbDataAdapter Lazy_data=new OleDbDataAdapter(Lazy_sql,Lazy_con);
38                 //定义OleDbDataAdapter对象实例并连接数据
39                 DataSet Lazy_set=new DataSet();
40                 //定义DataSet对象实例
41                 Lazy_data.Fill(Lazy_set);
42                 this.dataGridView1.DataSource=Lazy_set.Tables[].DefaultView;
43                 //链接数据表格，显示数据
44             }
45         }
46
47         void MainFormLoad(object sender, EventArgs e)
48         {
49             string Lazy_path=Application.StartupPath+“\\Lazy_Data.accdb”;
50                 //连接数据库的路径和数据库名
51             string Lazy_str=“Provider=Microsoft.ACE.OLEDB.12.0; Data Source=”+Lazy_path;
52                 //生成连接数据库字符串
53             Lazy_con=new OleDbConnection(Lazy_str);
54                 //定义OleDbConnection对象并连接数据库
55             Lazy_con.Open();
56                 //打开数据库
57             OleDbCommand Lazy_comm=new OleDbCommand(“select distinct(艺人) from LazyData”,Lazy_con);
58                 //定义OleDbcommand对象实例并连接数据库表
59             OleDbDataReader Lazy_read=Lazy_comm.ExecuteReader();
60                 //定义OleDbDataReader对象并读取信息
61             comboBox1.Items.Clear();
62             while(Lazy_read.Read())
63             {
64                 comboBox1.Items.Add(Lazy_read[].ToString());
65                     //把艺人信息添加到下拉列表中
66             }
67             Lazy_read.Close();
68                 //关闭OleDbDataReader对象实例
69             Lazy_read.Dispose();
70                 //释放OleDbDataReader对象所占内存空间
71         }
72     }
73 }