我如何从数据库中选择数据以显示在gridview中

问题描述

好吧，我是编码的新手，正在尝试弄清楚如何在Visual Studio C#中进行编码.我有一个数据库表，该表具有3列和10行.列标题为状态"，"ID"和"EmployeeName".在状态"列中，每行从#1到#4都有一位数字.我想做的是利用计时器每60秒检查一次此表，并返回状态ID大于1的任何行和列.这是我到目前为止的内容:

Ok I''m new to coding and am trying to figure out how I can code in Visual Studio C#. I have a database table that has 3 columns and 10 rows. The column headings are Status, ID, and EmployeeName. In the Status column, each row has a single digit from #1 to #4. What I want to do is utilize a timer to check this table every 60 seconds and return any row and column where the status ID is greater than 1. Here is what I have so far:

using System;
using System.Collections.Generic;
using System.Linq;
using System.Web;
using System.Web.UI;
using System.Web.UI.WebControls;
using System.Data.OleDb;
using System.Data;
using System.Data.SqlClient;
using System.Timers;
using System.ComponentModel;

public partial class Poll : System.Web.UI.Page
{
    protected void Page_Load(object sender, EventArgs e)
    {
    }
    public Poll()
    {
        InitializeComponent();
        timer.Interval = 60000;
        timer.Elapsed += new System.Timers.ElapsedEventHandler(timer_Elapsed);
    }
    private void InitializeComponent()
    {
    }
    System.Timers.Timer timer = new System.Timers.Timer();
    DataTable dt = new DataTable();
    void timer_Elapsed(object sender, System.Timers.ElapsedEventArgs e)
    {
        using (OleDbConnection con = new OleDbConnection("MAS2000"))
        {
            OleDbDataAdapter adapter = new OleDbDataAdapter("Insert * from SensorEvent", con);
            adapter.Fill(dt);
            DataRow[] rows = dt.Select("StatusID > ''1''");
            DataTable temp = new DataTable();
            temp.Columns.Add("StatusId", typeof(int));
            temp.Columns.Add("SensorID", typeof(String));
            temp.Columns.Add("UserID", typeof(String));
            //add columns to temp
            foreach (DataRow r in rows)
            {
                //add rows to temp as follows
                temp.Rows.Add(int.Parse(r[0].ToString()), r[1].ToString(), r[2].ToString());
            }
            this.dataGrid.DataSource = temp;

它显示了表格，但是如何仅导入所需结果(状态ID大于1)的功能不起作用.我得到整张桌子.因此，对此的任何帮助将不胜感激.

It brings up the tables but the function of how to only import the desired results(status id that is higher than 1) does not work. I get the whole table. So any help with this would be very much appreciated. Thanks

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