Controls are not inherited from other class

I have a function like this defined in one class:

using System;
using System.Collections.Generic;

using System.Linq;
using System.Text;

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

using System.Windows.Forms;
using Syste开发者_如何转开发m.Configuration;
using System.Diagnostics;
using MFDBAnalyser;

namespace MFDBAnalyser

{

    public class DataAccessMaster:MFDBAnalyser

    {


        //        /// <summary>
        //        /// This function gets the list of all the databases present in the local server.
        //        /// </summary>
        //        /// <returns></returns>


        public static DataSet GetAllDataBaseNames()

        {

            SqlConnectionStringBuilder objConnectionString = new SqlConnectionStringBuilder();
            objConnectionString.DataSource = txtHost.Text;
            objConnectionString.UserID = txtUsername.Text;
            objConnectionString.Password = txtPassword.Text;

            SqlConnection sConnection = new SqlConnection(objConnectionString.ConnectionString);

            //If connected then give this message to user
            lblMessage.Visible = true;
            lblMessage.Text = "You are connected to the SQL Server....";

            try
            {
                //To Open the connection.
                sConnection.Open();

                //Query to select the list of databases.
                string selectDatabaseNames = @"SELECT 
                                                    NAME 
                                                 FROM 
                                                    [MASTER]..[SYSDATABASES]";

                //Create the command object
                SqlCommand sCommand = new SqlCommand(selectDatabaseNames, sConnection);

                //Create the data set 
                DataSet sDataset = new DataSet("master..sysdatabases");

                //Create the dataadapter object
                SqlDataAdapter sDataAdapter = new SqlDataAdapter(selectDatabaseNames, sConnection);
                sDataAdapter.TableMappings.Add("Table", "master..sysdatabases");

                //Fill the dataset
                sDataAdapter.Fill(sDataset);

                //Bind the database names in combobox
                DataViewManager dsv = sDataset.DefaultViewManager;

            }
            catch(Exception ex)
            {
                //All the exceptions are handled and written in the EventLog.
                EventLog logException = new EventLog("Application");
                logException.Source = "MFDBAnalyser";
                logException.WriteEntry(ex.Message);
                MessageBox.Show("Login Failed!!", "Error Occured");
            }
            finally
            {
                //If connection is not closed then close the connection
                if(sConnection.State != ConnectionState.Closed)
                {
                    sConnection.Close();
                }
            }
        }
    }
}

And then I called this function in another class like this:

public void BindDBDropDown()

        {

 DataSet dsTablesWithoutForeignKeys = default(DataSet);

            try
            {
                //The function GetAllForeignKeyTables() is called from the class PluginManager.
                dsTablesWithoutForeignKeys = DataAccessMaster.GetAllDataBaseNames();

                cmbDatabases.DisplayMember = "TABLE_NAME";
                cmbDatabases.ValueMember = "";
                cmbDatabases.DataSource = dsTablesWithoutForeignKeys.Tables["master..sysdatabases"];
            }
            catch(Exception ex)
            {
                //All the exceptions are handled and written in the EventLog.
                EventLog logException = new EventLog("Application");
                logException.Source = "MFDBAnalyser";
                logException.WriteEntry(ex.Message);
            }
        }

But there is showing a error like txtHost etx doesn't exist and when I change the protected modifier of designer.cs class to public then also it is showing error...

Can anybody tell me whats is happening??

Assuming that your text boxes are defined in MFDBAnayser class, you still will not be able to access them in your GetAllDataBaseNames function. GetAllDataBaseNames is a static function and therefore it will not be able to access instance variables like the text boxes or other controls.

Verify that the modifier of txtHost is also protected or public.

U cannot get the values for a form in another class. Try using the parameters. Or use properties {get ;set;} to acess the values. I think u can use some property and assign the value of textbox. If u are doing in winforms it is Ok that u can use static variables.But in the case of web u must pass arguments.