Quick and Simple CSharp Windows Form

// Here is the entire program.  After playing around with it...seems to work.
// 2 labels, 2 buttons, a textbox, and a gridview.

    using System;  
    using System.Drawing; 
    using System.Windows.Forms;

    using System.Data;
    using System.Data.SqlClient;

    class MyForm : System.Windows.Forms.Form  
    {  
        Label label1;  
        Label label2;  
        TextBox txtbx1;  
        Button btn1;  
        Button exit;  

        DataGridView dataGridView1 = new DataGridView();
        BindingSource bindingSource1 = new BindingSource();
        SqlDataAdapter dataAdapter = new SqlDataAdapter();

        public MyForm()  
        {           
            label1 = new Label();  
            label2 = new Label();  
            txtbx1 = new TextBox();  
            btn1 = new Button();  
            exit = new Button(); 
 
            label1.UseMnemonic = true;  
            label1.Text = "Enter Server:";  
            label1.Location = new Point(20, 15); 
            label1.BackColor = System.Drawing.Color.Transparent; 
            //label1.BackColor = Color.LightGray;  
            label1.ForeColor = Color.Maroon;  
            label1.Size = new Size(label1.PreferredWidth, label1.PreferredHeight + 2);  

            txtbx1.Text = "";  
            txtbx1.Location = new Point(25 + label1.PreferredWidth + 5, 15);  
            txtbx1.BorderStyle = System.Windows.Forms.BorderStyle.FixedSingle;  
            txtbx1.BackColor = Color.LightGray;  
            txtbx1.ForeColor = Color.Maroon;  
            txtbx1.Size = new Size(110, 20);  

            btn1.Text = "&Run";  
            btn1.Location = new Point(15 + txtbx1.Location.X + txtbx1.Size.Width, 15);  
            btn1.Size = new Size(50, 20);  
 
            label2.UseMnemonic = true;  
            label2.Text = "                                                                               ";  
            label2.Location = new Point(100 + txtbx1.Location.X + btn1.Location.X , 15);  
            label2.BackColor = Color.LightGray;  
            label2.ForeColor = Color.Maroon;  
            label2.BorderStyle = System.Windows.Forms.BorderStyle.FixedSingle;  
            label2.Size = new Size(500,20);
            label2.AutoSize = true;

  
            exit.Text = "Exit";  
            exit.Location = new Point(60 + btn1.Location.X , 15);  
            exit.Size = new Size(50, 20);  
            exit.BackColor = Color.Maroon;  
            exit.ForeColor = Color.White;

            dataGridView1.Location = new Point(15, 50);
            dataGridView1.Size = new Size(1000,500);
            dataGridView1.BorderStyle = System.Windows.Forms.BorderStyle.FixedSingle;  
            dataGridView1.AutoSizeColumnsMode = DataGridViewAutoSizeColumnsMode.DisplayedCells;

            //Text to be Displayed in the Caption-Title Bar  
            this.Text = "CSharp Form for SQL Server";  
            this.StartPosition = FormStartPosition.CenterScreen;  
            this.AutoScaleBaseSize = new Size(5, 13);  
            this.ClientSize = new Size(1100, 600); //Size except the Title Bar-CaptionHeight  
            this.AutoScroll = true;  
            this.MaximizeBox = false;  
            this.Controls.Add(label1);  
            this.Controls.Add(txtbx1);  
            this.Controls.Add(btn1);  
            this.Controls.Add(exit); 
            this.Controls.Add(label2);  
            this.Controls.Add(dataGridView1); 

            btn1.Click += new EventHandler(Btn_Clicked);  
            exit.Click += new EventHandler(Ext_Clicked);  
        }  
//// Next part runs when the RUN button is clicked.
        public void Btn_Clicked(object ob, EventArgs e)  
        { 
         if (string.IsNullOrEmpty(txtbx1.Text))
            {
                MessageBox.Show("PLEASE ENTER A SERVER ", "ERROR");
            }
            else
            {
                string connectionString = "Data Source=" + txtbx1.Text + ";Initial Catalog=msdb;Integrated Security=True";
           // Next line if you try to use a drop-down
           //     string connectionString = "Data Source=" + comboBoxServ1.Text + ";Initial Catalog=msdb;Integrated Security=True";

                using (SqlConnection SqlCon = new SqlConnection(connectionString))
                {
                    try
                    {
                        SqlCon.Open();
                    }
                    catch
                    {
                        MessageBox.Show("Cant connect to the server. Check your spelling. ", "Connect ERROR");
                    }

                    //  string sql = "select top 20 server_name, backup_finish_date, database_name from backupset where database_name = ''msdb'';";

                    string sql =
                   "Create Table #dbInfo (dId smallint, tgroupID smallint NULL, dbName sysname,  segName varchar(256) NULL, " +
                          " filName varchar(520) NULL, sizeMg decimal(10,2) null, " +
                          " usedMg decimal(10,2) null,  " +
                         " pcntUsed decimal(10,2) null, backup_finish_date Datetime null, recov_type char(15) NULL ) " +
                   " Declare @sSql varchar(1000) " +
                   " Set @sSql = 'Use [?]; " +
                   " Insert #dbInfo (dId, tgroupID, dbName, segName, filName, sizeMg, usedMg, recov_type) " +
                   " Select db_id(), groupid, db_name(),  rtrim(name), filename, Cast(size/128.0 As Decimal(10,2)), " +
                   " Cast(Fileproperty(name, ''SpaceUsed'')/128.0 As Decimal(10,2)), CAST(DATABASEPROPERTYEX(db_name(),  ''RECOVERY''  ) as CHAR(15)) " +
                   " From dbo.sysfiles Order By groupId Desc; ' " +

                   " Exec sp_MSforeachdb @sSql " +
                   " Update #dbInfo Set " +
                   " pcntUsed = (usedMg/sizeMg)*100 " +

                   " Update db  " +
                   " Set db.backup_finish_date = T2.backup_finish_date  " +
                   " From msdb.dbo.backupset T2 " +
                   " Inner Join #dbInfo db on (db.dbName =T2.database_name) " +
                   " where db.dbName = T2.database_name " +
                   " and T2.type = 'D' " +
                   " and db.tgroupID > 0 " +
                   "  and T2.backup_finish_date =   " +
                   " (select MAX(backup_finish_date) from msdb.dbo.backupset T3 inner join msdb.dbo.backupmediafamily bmf on (T3.media_set_id = bmf.media_set_id) " +
                   "  where T3.database_name = T2.database_name and T3.type='D'  AND LEFT(bmf.physical_device_name,1) <> '{') " +

                   " Update db " +
                   " Set db.backup_finish_date = T2.backup_finish_date " +
                   " From msdb.dbo.backupset T2 " +
                   " Inner Join #dbInfo db on (db.dbName =T2.database_name) " +
                   " where db.dbName = T2.database_name  " +
                   " and T2.type = 'L' " +
                   "  and db.tgroupID = 0 " +
                   "  and T2.backup_finish_date =  (select MAX(backup_finish_date) from msdb.dbo.backupset T3 where T3.database_name = T2.database_name and T3.type='L' ) " +

                   " select dbName, segName as 'FileGroup', sizeMg as 'DB Size MB',  pcntUsed as '% Used', recov_type as 'Recovery Type', backup_finish_date as 'Backup Date', filName as 'File' from #dbInfo " +
                   " drop table #dbInfo ";

                    try
                    {
/// Next lines fill a data table and bind to the gridview.
                        SqlDataAdapter sqlDa = new SqlDataAdapter(sql, SqlCon);
                        DataTable dtb1 = new DataTable();
                        sqlDa.Fill(dtb1);
                        dataGridView1.DataSource = dtb1;
/// Next lines setup version info.  There are linefeeds in @@version hence the LEFT.
                        SqlCommand sqlcmd1 = new SqlCommand("Select LEFT(@@version,charindex(char(10),@@version)-1);", SqlCon);
                        SqlDataReader da = sqlcmd1.ExecuteReader();
                        while (da.Read())
                        {
                            label2.Text = da.GetValue(0).ToString();
                        }

                    }
                    catch
                    {
                     // Next line used to debug if you try new/changed query
                     //  MessageBox.Show("query= " + sql, "ERROR");
                    }

                }
            }  //end blank server  
         
        }  
        public void Ext_Clicked(object ob, EventArgs e)  
        {  
            Application.Exit();  
            MessageBox.Show("Successfully Closed", "EXIT");//not Shown! Do you know Why?  
        }  
        public static void Main()  
        {  
            Application.Run(new MyForm());  
        }  
    }