Why my Searcher App crash and how to handle it ?

I wrote a File-Searcher Windows Application (with .NET 4.5) and use Async technique to search faster without locking the GUI.

It tracks it's directory to find files with the given name and extension.

I used Linq Query instead of iterating on files using foreach. (Is it better than foreach ? )

It works great! but it just has a problem. It crashes rapidly!

As I write more than 2 character in the text box, it STOPS WORKING . . .

Do you have any idea that what cause it and how shall I handle it ?

This is my app :

Dictionary<string, string> DS = new Dictionary<string, string>();

        //

        public Form1()
        {
            InitializeComponent();
        }

        //

        private void Form1_Load(object sender, EventArgs e)
        {
        }

        private void Txt_Text_TextChanged(object sender, EventArgs e)
        {
            try
            {
                if (!String.IsNullOrWhiteSpace(this.Txt_Text.Text))
                {
                    Action a = new Action(Search_Name);
                    a.BeginInvoke(AsyncCore, a);
                }
            }
            catch (Exception ex)
            {
                MessageBox.Show(ex.Message);
            }
        }

        private void Txt_Ext_TextChanged(object sender, EventArgs e)
        {
            try
            {
                if (!String.IsNullOrWhiteSpace(this.Txt_Ext.Text))
                {
                    Action a = new Action(Search_Ext);
                    a.BeginInvoke(AsyncCore, a);
                }
            }
            catch (Exception ex)
            {
                MessageBox.Show(ex.Message);
            }
        }
/// <summary>
        /// To open the file that listed. (On user's click)
        /// </summary>
        private void ListBox_SelectedIndexChanged(object sender, EventArgs e)
        {
            try
            {
                string FPath = (from x in DS
                                where x.Key == this.ListBox.SelectedItem.ToString()
                                select x.Value).Single();

                Process.Start(FPath);
            }
            catch (Exception ex)
            {
                MessageBox.Show(ex.Message);
            }
        }

        //

        void Search_Name()
        {
            try
            {
                DirectoryInfo DI = new DirectoryInfo(Environment.CurrentDirectory);

                var Q = from FileInfo x in DI.GetFiles()
                        where x.Name.Contains(this.Txt_Ext.Text)
                        select new { FName = x.Name , FPath = x.FullName };

                foreach (var item in Q)
                {
                    DS.Add(item.FName, item.FPath);
                }
            }
            catch (Exception ex)
            {
                throw ex;
            }
        }

        void Search_Ext()
        {
            try
            {
                DirectoryInfo DI = new DirectoryInfo(Environment.CurrentDirectory);

                var Q = from FileInfo x in DI.GetFiles()
                        where x.Extension == "." + this.Txt_Ext.Text
                        select new { FName = x.Name, FPath = x.FullName };

                foreach (var item in Q)
                {
                    DS.Add(item.FName, item.FPath);
                }
            }
            catch (Exception ex)
            {
                throw ex;
            }
        }

        void FillListBox()
        {
            try
            {
                this.ListBox.Items.Clear();

                foreach (KeyValuePair<string, string> item in DS)
                {
                    this.ListBox.Items.Add(item.Key);
                }
            }
            catch (Exception ex)
            {
                throw ex;
            }
        }

        void AsyncCore(IAsyncResult ar)
        {
            try
            {
                Action a = (Action)ar.AsyncState;

                a.EndInvoke(ar);

                this.Invoke((MethodInvoker)delegate
                {
                    FillListBox();
                });
            }
            catch (Exception ex)
            {
                throw ex;
            }
        }

Hamed Shams The consultant and executer of IT projects. Windows and Web programmer based on Microsoft technology.