Word Automation

using System;
using System.IO;
using System.Text;
using System.Data;
using System.Drawing;
using System.Windows.Forms;
using System.ComponentModel;
using Automation;

namespace AutomationTest
{
    public partial class Automation : Form
    {
        private object _wordApplication = null;
        private object _wordDocument = null;
        public Automation()
        {
            InitializeComponent();            
        }

        private void btnBrowse_Click(object sender, EventArgs e)
        {
            WordAutomation automation = new WordAutomation();
            if (_wordApplication == null)
            {
                 _wordApplication = automation.CreateWordApplication();
            }           
            OpenFileDialog dlg = new OpenFileDialog();
            dlg.Filter = "All word documents(*.doc)|*.doc";
            if (DialogResult.OK == dlg.ShowDialog(this))
            {
                if (File.Exists(dlg.FileName))
                {
                    if (_wordDocument != null)
                    {
                        automation.CloseWordDoc(_wordDocument, true);
                    }
                    _wordDocument = automation.CreateWordDoc(
                        dlg.FileName, _wordApplication, false);
                    txtFileName.Text = dlg.FileName;
                }
            }
        }

        private void btnGetCount_Click(object sender, EventArgs e)
        {
            lblCount.Text = string.Empty;
            if (_wordApplication != null && _wordDocument != null)
            {
                if (txtFind.Text.Trim().Length == 0)
                {
                    MessageBox.Show("Enter a text to find.", AppName,
                        MessageBoxButtons.OK, MessageBoxIcon.Warning);
                }
                int count = new WordAutomation().GetWordCount(
                    _wordDocument, txtFind.Text.Trim());
                lblCount.Text = count.ToString();
            }
            else
            {
                MessageBox.Show("Open a valid document to continue.", AppName,
                        MessageBoxButtons.OK, MessageBoxIcon.Warning);
            }
        }
        public string AppName
        {
            get
            {
                return "Word Automation";
            }
        }

        private void Automation_FormClosing(object sender, FormClosingEventArgs e)
        {
            if (_wordDocument != null)
            {
                new WordAutomation().CloseWordDoc(_wordDocument, true);
            }
            if (_wordApplication != null)
            {                
                new WordAutomation().CloseWordApp(_wordApplication);
            }
        }

        private void btnReplaceAll_Click(object sender, EventArgs e)
        {
            if (_wordApplication != null && _wordDocument != null)
            {
                if (txtFind.Text.Trim().Length == 0)
                {
                    MessageBox.Show("Enter a text to find.", AppName,
                        MessageBoxButtons.OK, MessageBoxIcon.Warning);
                    return;
                }
                if (txtReplace.Text.Trim().Length == 0)
                {
                    MessageBox.Show("Enter a text to replace.", AppName,
                       MessageBoxButtons.OK, MessageBoxIcon.Warning);
                    return;
                }
                new WordAutomation().FindReplace(_wordDocument, 
                    _wordApplication, txtFind.Text.Trim(), txtReplace.Text.Trim());
                MessageBox.Show("Replaced successfully.", AppName,
                       MessageBoxButtons.OK, MessageBoxIcon.Information);
            }
            else
            {
                MessageBox.Show("Open a valid document to continue.", AppName,
                       MessageBoxButtons.OK, MessageBoxIcon.Warning);
            }
        }
    }
}