当我运行程序时网格不显示数据 [英] Grid does not show data when i run the program

问题描述

我绑定了网格，但是当我运行程序时，数据库中的数据没有显示.请检查下面的代码！

I bind the grid but when I run the program, the data in the database is not showing. Please check the code below!

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.SqlClient;

namespace Company
{
    public partial class Form1 : Form
    {
        public string conStr = "Data Source=MINDWORK2;Initial Catalog=myworld;Integrated Security=True";
        public Form1()
        {
            InitializeComponent();
            BindCompany();
        }

        public void BindCompany()
        {
            SqlConnection con;
            SqlDataAdapter da;
            SqlCommandBuilder cmd;
            //DataRow row;
            DataSet ds = new DataSet();
            BindingSource bsourse = new BindingSource();

            con = new SqlConnection(conStr);
            da = new SqlDataAdapter("select * from company", con);
            cmd = new SqlCommandBuilder(da);
            da.Fill(ds, "company");
            dg.DataSource = ds.Tables["company"];
            dg.DataSource = bsourse;
        }

        public int GetNextId(string tableName)
        {
            //Here code for getting next id from database. 
            int id = 0;
            SqlConnection conn = new SqlConnection(conStr);
            conn.Open();

            string query = "SELECT MAX(ISNULL(id,0))+1 AS ID FROM COMPANY";

            SqlCommand command = new SqlCommand();
            command.CommandText = query;
            command.CommandType = CommandType.Text;
            command.Connection = conn;
            try
            {
                SqlDataReader reader = command.ExecuteReader();
                if (reader.Read())
                {
                    id = int.Parse(reader["ID"].ToString());
                }
            }
            catch (Exception exc)
            {
                MessageBox.Show("Exception getting next id: " + exc.Message);
            }
            finally
            {
                conn.Close();
                conn = null;
            }

            return id;
        }

        public bool InsertCompany(int id)
        {
            bool result = false;

            SqlConnection conn = new SqlConnection(conStr);
            conn.Open();

            string query = "INSERT INTO COMPANY(ID,NAME,LOGIN,PASSWORD) VALUES(@ID, @NAME, @LOGIN, @PASSWORD)";

            SqlCommand command = new SqlCommand();
            command.CommandText = query;
            command.CommandType = CommandType.Text;
            command.Connection = conn;
            command.Parameters.Add("@ID", SqlDbType.Int).Value = id;
            command.Parameters.Add("@NAME", SqlDbType.VarChar).Value = txtName.Text;
            command.Parameters.Add("@Login", SqlDbType.VarChar).Value = txtLogin.Text;
            command.Parameters.Add("@Password", SqlDbType.VarChar).Value = txtPassword.Text;

            try
            {
                command.ExecuteNonQuery();
                result = true;
            }
            catch (Exception exc)
            {
                MessageBox.Show("Exception in inserting record: " + exc.Message);
            }
            finally
            {
                conn.Close();
                conn = null;
            }
            return result;
        }

        public bool DeleteCompany(int id)
        {
            bool result = false;

            SqlConnection conn = new SqlConnection(conStr);
            conn.Open();

            string query = "DELETE FROM COMPANY WHERE ID = " + id;

            SqlCommand command = new SqlCommand();
            command.CommandText = query;
            command.CommandType = CommandType.Text;
            command.Connection = conn;

            try
            {
                command.ExecuteNonQuery();
                result = true;
            }
            catch (Exception exc)
            {
                MessageBox.Show("Exception in deleting record: " + exc.Message);
            }
            finally
            {
                conn.Close();
                conn = null;
            }
            return result;
        }

        private void btnAdd_Click(object sender, EventArgs e)
        {
            int id = GetNextId("company");
            if (InsertCompany(id))
            {
                MessageBox.Show("Record inserted");
            }
            else
            {
                MessageBox.Show("Unable to insert record");
            }
        }

        private void btnDel_Click(object sender, EventArgs e)
        {
            int id = 5;
            if (DeleteCompany(id))
            {
                MessageBox.Show("Record deleted successfully");
            }
            else
            {
                MessageBox.Show("Unable to delete record");
            }
        }

        private void button1_Click(object sender, EventArgs e)
        {
            monthCalendar1.Visible = true;
        }

    }
}

推荐答案

您忘记了数据绑定

dg.DataSource = ds.Tables ["company"];
dg.DataBind();

You forgot to databind

dg.DataSource = ds.Tables["company"];
dg.DataBind();

这篇关于当我运行程序时网格不显示数据的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！