[原创]作业：家庭消费管理程序，一点代码

最后的图：

操作数据库的 DBconn.cs:

using System;
using System.Collections.Generic;
using System.Text;
using System.Data;
using System.Data.OleDb;

//数据类
namespace winfamily
{
    class DBconn
    {
      private OleDbConnection conn;
        //属性
        public OleDbConnection Conn
        {
            get { return conn; }
        }
        //连接数据库
        public  DBconn(string sql)
        {
            conn = new OleDbConnection(sql);
        }
        //取得数据集
        public DataSet getdb(string str)
        {
            Conn.Open();
            OleDbDataAdapter oleda;
            oleda = new OleDbDataAdapter(str,Conn);
            DataSet ds = new DataSet();
            oleda.Fill(ds);
            //关闭
            Conn.Close();
            return ds;
        }
    }
}

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应用程序的配置文件： App.conifg：

<?xml version="1.0" encoding="utf-8" ?>
<configuration>
  <appSettings>
    <add key="sql" value="provider=Microsoft.Jet.OLEDB.4.0;data source=db.mdb"/>
  </appSettings>
</configuration>
---------------------------
提交消费信息的代码（当然，最好使用参数插入到数据库）：
//提交消费信息到数据库
    private void button1_Click(object sender, EventArgs e)
    {
        //得到数据库 表需要的数据
        string time = xfDatetime.Text;
        string type = xfType.SelectedItem.ToString();
        double money =double.Parse(xfMoney.Text);
        string address = xfAddress.Text;
        string person = xfPerson.Text;
        string info = xfInfo.Text;
        //插入数据
        string str = "insert into expenditure(消费日期,消费类别,消费金额,消费地点,消费者,备注说明) " +
            "values(#" + time + "#,'" + type + "'," + money + ",'" + address + "','" + person + "','" + info + "')";
        //执行SQL操作
        DBconn dbClass = new DBconn(sql);
        OleDbCommand command = new OleDbCommand(str, dbClass.Conn);
        dbClass.Conn.Open();
        command.ExecuteNonQuery();
        dbClass.Conn.Close();
        MessageBox.Show("提交成功！");
    }

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查询消费信息的代码：

//查询信息
    private void button2_Click(object sender, EventArgs e)
    {
        //查询语句
        string str = "select * from expenditure ";
        if (cxType.SelectedItem.ToString().Trim() != "")
            str +=  "where 消费类别='" + cxType.SelectedItem.ToString()+"'";
        if (cxperson.SelectedItem.ToString().Trim() != "")
            str +=  " and  消费者='" + cxperson.SelectedItem.ToString()+"'";
        str += " and  消费日期>= #" + cxBegintime.Value.ToShortDateString() + "#  and 消费日期<= #" + cxEndTime.Value.ToShortDateString() + "# ";
        MessageBox.Show(str);
        //执行查询
        DBconn dbClass=new DBconn(sql);
        OleDbCommand olecommand = new OleDbCommand(str, dbClass.Conn);
        dbClass.Conn.Open();
        olecommand.ExecuteNonQuery();
        dbClass.Conn.Close();
        //显示查询
        DataSet ds = dbClass.getdb(str);
        dataGridView1.DataSource = ds.Tables[0];

    }
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一小段代码！