Read/Write Web.config File

To modify the web.config [AppSettings] keys value at runtime
in grid like format using asp.net 2.0

1) Create a class in App_Code and copy & paste the below code

//Create an entity to store the config key and value

    public class AppSettingsKeys
    {
      
        int _configID;
       
        int _conID;
        string _conName;
        string _conValue;

        string _configName;
        string _configValue;

        public AppSettingsKeys()
        {
            this._configID = 0;
            this._configName = string.Empty;
            this._configValue = string.Empty;
           
            this._conID = 0;
            this._conName = string.Empty;
            this._conValue = string.Empty;
        }

        public int ConID
        {
            get { return _conID; }
            set { _conID = value; }
        }

        public string ConnectionName
        {
            get { return _conName; }
            set { _conName = value; }
        }

        public string ConnectionValue
        {
            get { return _conValue; }
            set { _conValue = value; }
        }

        public int ConfigID
        {
            get { return _configID; }
            set { _configID = value; }
        }
        public string ConfigName
        {
            get { return _configName; }
            set { _configName = value; }
        }
        public string ConfigValue
        {
            get { return _configValue; }
            set { _configValue = value; }
        }

        public void SetInfo(int id, string configName, string configValue)
        {
            this.ConfigID = id;
            this._configName = configName;
            this._configValue = configValue;
        }
    }
 
//2) Create a collection class like the below:

    public class AppSettingsKeysList : List
    { }

    public class AppSettingsOperations
    {
        //get all keys

        public AppSettingsKeysList getAllAppSettingsKeys()
        {
            AppSettingsKeys appSettingKey = null;
            AppSettingsKeysList appSettingKeyList = new AppSettingsKeysList();
            int idCount = 0;

            Configuration configuration = WebConfigurationManager.OpenWebConfiguration("~");
            AppSettingsSection appSettingsSection = (AppSettingsSection) configuration.GetSection("appSettings");

            ConnectionStringsSection ConStringSection = (ConnectionStringsSection)configuration.GetSection("connectionStrings");
           
            if (appSettingsSection != null)
            {
                foreach (string key in appSettingsSection.Settings.AllKeys)
                {
                    idCount++;
                    appSettingKey = new AppSettingsKeys();
                    appSettingKey.ConfigID = idCount;
                    appSettingKey.ConfigName = key;
                    appSettingKey.ConfigValue = appSettingsSection.Settings[key].Value;

                    appSettingKeyList.Add(appSettingKey);
                }
            }
            return appSettingKeyList;
        }

        //modify the key List

        public bool ModifyKey(AppSettingsKeys appSettingKeys)
        {
            try
            {
                Configuration configuration = WebConfigurationManager.OpenWebConfiguration("~");
                AppSettingsSection appSettingsSection =(AppSettingsSection) configuration.GetSection("appSettings");

                if (appSettingsSection != null)
                {
                    appSettingsSection.Settings[appSettingKeys.ConfigName].Value = appSettingKeys.ConfigValue;
                    configuration.Save();
                }
            }
            catch (Exception errorObject)
            {
                return false;
            }
            return true;
        }

    }

4) Create an aspx page and paste the below code:


 protected void Page_Load(object sender, EventArgs e)
    {

        lblMsg.Text = string.Empty;

       
       
        if (!IsPostBack)
        {
            //calling the method for papulating all app Settings keys
            try
            {
                GetAppSettingsKeys();
            }
            catch (Exception ex)
            {
                ExceptionMethod(ex);
            }
        }
    }
    private void ExceptionMethod(Exception errorObject)
    {
        lblMsg.Text = errorObject.Message.ToString();
        lblMsg.ForeColor = System.Drawing.Color.Red;
    }

    private void BindGridView(AppSettingsKeysList allKeyList)
    {
        try
        {
            GVAppConfig.DataSource = allKeyList;
            GVAppConfig.DataBind();
        }
        catch (Exception ex)
        {
            throw ex;
        }
    }

    private void GetAppSettingsKeys()
    {
        AppSettingsOperations appSettingsOperations = new AppSettingsOperations();
        AppSettingsKeysList appSettingsKeyList = new AppSettingsKeysList();

        try
        {
            appSettingsKeyList = appSettingsOperations.getAllAppSettingsKeys();
            if (appSettingsKeyList.Count > 0)
            {
                //calling the bind gridView Method
                BindGridView(appSettingsKeyList);
            }
            else
            {
                lblMsg.Text = ">> No Keys Avaliable..!";
            }
        }
        catch (Exception ex)
        {
            throw ex;
        }
    }

    protected void GVAppConfig_PageIndexChanging(object sender, GridViewPageEventArgs e)
    {
        try
        {
            GVAppConfig.PageIndex = e.NewPageIndex;
            GetAppSettingsKeys();
        }
        catch (Exception ex)
        {
            ExceptionMethod(ex);
        }
    }
    protected void GVAppConfig_RowCancelingEdit(object sender, GridViewCancelEditEventArgs e)
    {
        try
        {
            GVAppConfig.EditIndex = -1;
            GetAppSettingsKeys();
        }
        catch (Exception ex)
        {
            ExceptionMethod(ex);
        }
    }
    protected void GVAppConfig_RowEditing(object sender, GridViewEditEventArgs e)
    {
        try
        {
            GVAppConfig.EditIndex = e.NewEditIndex;
            GetAppSettingsKeys();
        }
        catch (Exception ex)
        {
            ExceptionMethod(ex);
        }
    }
    protected void GVAppConfig_RowUpdating(object sender, GridViewUpdateEventArgs e)
    {
        AppSettingsKeys appSettings = new AppSettingsKeys();
        AppSettingsOperations appSettingOperation = new AppSettingsOperations();

        try
        {
            Label lblKey = (Label) GVAppConfig.Rows[e.RowIndex].Cells[2].Controls[1];
            TextBox txtValue =(TextBox) GVAppConfig.Rows[e.RowIndex].FindControl("txtConfigValue");
           
            appSettings.ConfigID = Convert.ToInt32(GVAppConfig.DataKeys[e.RowIndex].Value);
            appSettings.ConfigValue = txtValue.Text;
            appSettings.ConfigName = lblKey.Text;

            //Update the key with the user entered value
            if (appSettingOperation.ModifyKey(appSettings))
            {
                lblMsg.ForeColor = System.Drawing.Color.Green;
                lblMsg.Text = ">> Key has been sucessfully updated...!";
            }
            else
            {
                lblMsg.ForeColor = System.Drawing.Color.Red;
                lblMsg.Text = ">> There is some problem in updating the key ,try later....!";
            }

            GVAppConfig.EditIndex = -1;
            GetAppSettingsKeys();
        }
        catch (Exception ex)
        {
            ExceptionMethod(ex);
        }
    }