Load data by Thread

C#:

I want to load big data from Database and in loading progress i want display available to DatagridView. I use IDataReader and BackgroundWorker. But in hard try some way, i get error. I want when Execute Script to server, the data receive will have Schema information, and it 开发者_开发问答will dynamic to create structure of DatagridView and base from that structure the available data will add to grid row by row and User can see this changed. My code is below, but error. Any answer to help my I deal, i thanks very much!

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 WindowsFormsApplication1
{
    partial class Form1
    {

        string conectionString = "";

        IDbConnection connection;

        BackgroundWorker worker;

        BindingSource binding;

        IDbCommand GetExecuteCommand()
        {
            string commandText = "select * from dbo.B20DmBp";
            SqlCommand command = new SqlCommand();
            command.Connection = (SqlConnection)this.connection;
            command.CommandText = commandText;
            command.CommandType = CommandType.Text;
            return command;
        }

        public Form1()
        {
            InitializeComponent();
            Initialize();
            RegisterHandler();
        }

        void Initialize()
        {
            worker = new BackgroundWorker();
            worker.WorkerSupportsCancellation = true;
            worker.WorkerReportsProgress = true;

            binding = new BindingSource();
            this.dataGridView1.DataSource = binding;
            connection = new SqlConnection(conectionString);
        }

        void RegisterHandler()
        {
            worker.DoWork += new DoWorkEventHandler(worker_DoWork);
            worker.RunWorkerCompleted += new RunWorkerCompletedEventHandler(worker_RunWorkerCompleted);
            worker.ProgressChanged += new ProgressChangedEventHandler(worker_ProgressChanged);
        }

        void worker_ProgressChanged(object sender, ProgressChangedEventArgs e)
        {
            DataTable table = this.binding.DataSource as DataTable;

            IDataReader reader = e.UserState as IDataReader;

            table.Rows.Add(this.BuildDataRow(reader));

            this.binding.ResetBindings(false);
        }

        void worker_DoWork(object sender, DoWorkEventArgs e)
        {
            IDbCommand command = e.Argument as IDbCommand;

            BackgroundWorker worker2 = sender as BackgroundWorker;

            try
            {
                command.Connection.Open();
                IDataReader reader = command.ExecuteReader();

                while (reader.Read())
                {
                    if (worker.CancellationPending)
                    {
                        e.Cancel = true;
                    }
                    else
                    {
                        worker.ReportProgress(0, reader);
                    }
                }

                reader.Close();
                command.Connection.Close();
            }
            catch (Exception)
            {
                throw;
            }
            finally
            {
                command.Connection.Close();
            }
        }

        void worker_RunWorkerCompleted(object sender, RunWorkerCompletedEventArgs e)
        {
            throw new NotImplementedException();
        }

        void StartExecute()
        {
            this.binding.DataSource = new DataTable();

            this.worker.RunWorkerAsync(this.GetExecuteCommand());
        }

        void CancelExecute()
        {
            if (this.worker.WorkerSupportsCancellation)
            {
                this.worker.CancelAsync();
            }
        }

        DataRow BuildDataRow(IDataReader reader)
        {
            DataTable table = this.binding.DataSource as DataTable;

            if (table.Columns.Count == 0)
            {
                foreach (DataRow row in reader.GetSchemaTable().Rows)
                {
                    string columnName = row["ColumnName"].ToString();
                    table.Columns.Add(columnName);
                }

                this.binding.ResetBindings(true);
            }

            DataRow row2 = table.NewRow();

            foreach (DataRow row in reader.GetSchemaTable().Rows)
            {
                string columnName = row["ColumnName"].ToString();
                row2[columnName] = reader[columnName];
            }

            return row2;
        }

        private void button1_Click(object sender, EventArgs e)
        {
            this.StartExecute();
        }

        private void button2_Click(object sender, EventArgs e)
        {
            this.CancelExecute();
        }



















        /// <summary>
        /// Required designer variable.
        /// </summary>
        private System.ComponentModel.IContainer components = null;

        /// <summary>
        /// Clean up any resources being used.
        /// </summary>
        /// <param name="disposing">true if managed resources should be disposed; otherwise, false.</param>
        protected override void Dispose(bool disposing)
        {
            if (disposing && (components != null))
            {
                components.Dispose();
            }
            base.Dispose(disposing);
        }

        #region Windows Form Designer generated code

        /// <summary>
        /// Required method for Designer support - do not modify
        /// the contents of this method with the code editor.
        /// </summary>
        private void InitializeComponent()
        {
            this.dataGridView1 = new System.Windows.Forms.DataGridView();
            this.button1 = new System.Windows.Forms.Button();
            this.button2 = new System.Windows.Forms.Button();
            ((System.ComponentModel.ISupportInitialize)(this.dataGridView1)).BeginInit();
            this.SuspendLayout();
            // 
            // dataGridView1
            // 
            this.dataGridView1.ColumnHeadersHeightSizeMode = System.Windows.Forms.DataGridViewColumnHeadersHeightSizeMode.AutoSize;
            this.dataGridView1.Location = new System.Drawing.Point(35, 26);
            this.dataGridView1.Name = "dataGridView1";
            this.dataGridView1.Size = new System.Drawing.Size(240, 150);
            this.dataGridView1.TabIndex = 0;
            // 
            // button1
            // 
            this.button1.Location = new System.Drawing.Point(35, 194);
            this.button1.Name = "button1";
            this.button1.Size = new System.Drawing.Size(75, 23);
            this.button1.TabIndex = 1;
            this.button1.Text = "button1";
            this.button1.UseVisualStyleBackColor = true;
            this.button1.Click += new System.EventHandler(this.button1_Click);
            // 
            // button2
            // 
            this.button2.Location = new System.Drawing.Point(127, 194);
            this.button2.Name = "button2";
            this.button2.Size = new System.Drawing.Size(75, 23);
            this.button2.TabIndex = 2;
            this.button2.Text = "button2";
            this.button2.UseVisualStyleBackColor = true;
            this.button2.Click += new System.EventHandler(this.button2_Click);
            // 
            // Form1
            // 
            this.AutoScaleDimensions = new System.Drawing.SizeF(6F, 13F);
            this.AutoScaleMode = System.Windows.Forms.AutoScaleMode.Font;
            this.ClientSize = new System.Drawing.Size(323, 262);
            this.Controls.Add(this.button2);
            this.Controls.Add(this.button1);
            this.Controls.Add(this.dataGridView1);
            this.Name = "Form1";
            this.Text = "Form1";
            ((System.ComponentModel.ISupportInitialize)(this.dataGridView1)).EndInit();
            this.ResumeLayout(false);

        }

        #endregion

        private System.Windows.Forms.DataGridView dataGridView1;
        private System.Windows.Forms.Button button1;
        private System.Windows.Forms.Button button2;
    }
}

Are cross thread access error occurs? if yes, you can resolve as in topic: http://msdn.microsoft.com/en-us/library/ms171728%28VS.80%29.aspx