在 gridview 中显示 oracle 数据库值

Question

您好，我有一个带有 3 列 NOME、COGNOME、NUMTELEFONO 的表 PROVA 的 oracle 数据库。 我正在搜索用包含在表中的值来更新我在 c# 中的 gridview。 这是我的代码，在 button1_Click() 方法中，我需要在我的 gridview c# 应用程序中显示 db 值。有人可以帮我写代码吗？

using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Data;
using System.Data.OracleClient;
using System.Drawing;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
using System.Windows.Forms;
using Oracle.ManagedDataAccess;



namespace dbOracleForm
{
    public partial class Form1 : Form
    {
        

        public Form1()
        {
            InitializeComponent();
        }

        private void label2_Click(object sender, EventArgs e)
        {

        }

        private void label1_Click(object sender, EventArgs e)
        {

        }

        private void button1_Click(object sender, EventArgs e)
        {
            String connectionString = "Data Source =  (DESCRIPTION = "+
    "(ADDRESS = (PROTOCOL = TCP)(HOST = localhost)(PORT = 1521))" +
    "(CONNECT_DATA = " +
     " (SERVER = DEDICATED) " + 
     " (SERVICE_NAME = orcl.home) " +
    ")"+
  "); User Id = system;password = orcl;";
            OracleConnection  con = new OracleConnection();
            con.ConnectionString = connectionString;

            con.Open();

            OracleCommand cmd = new OracleCommand();
            cmd.CommandText = "SELECT NOME, COGNOME, NUMTELEFONO FROM PROVA ORDER BY COGNOME DESC";
            cmd.CommandType = CommandType.Text;
            OracleDataReader dr = cmd.ExecuteReader();
            DataTable dt = new DataTable();
            dt.Load(dr);
            dataGridView1.DataSource(dt);



        }


        private void Form1_Load(object sender, EventArgs e)
        {

        }
    }
}

Answer 1

你可以这样做

 private void button1_Click(object sender, EventArgs e)
    {
       ...

        OracleCommand cmd = new OracleCommand();
        cmd.CommandText = "SELECT NOME, COGNOME, NUMTELEFONO FROM PROVA ORDER BY COGNOME DESC";
        cmd.CommandType = CommandType.Text;
        OracleDataReader dr = cmd.ExecuteReader();
        DataTable dt = new DataTable();
        dt.Load(dr);

        dataGridView1.DataSource(dt);//wrong
        dataGridView1.DataSource= dt;//correct



    }