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public class ExtendedImageField : DataControlField

#region Propiedades

/// <summary>

/// Gets or sets the image URL.

/// </summary>

/// <value>The image URL.</value>

public string ImageUrl

{

    get { return _imageUrl; }

    set { _imageUrl = value; }

}

/// <summary>

/// Gets or sets the name of the property.

/// </summary>

/// <value>The name of the property.</value>

public string PropertyName

{

    get { return _propertyName; }

    set { _propertyName = value; }

}

#endregion

/// <summary>

/// When overridden in a derived class, creates an empty <see cref="T:System.Web.UI.WebControls.DataControlField"/>-derived object.

/// </summary>

/// <returns>

/// An empty <see cref="T:System.Web.UI.WebControls.DataControlField"/>-derived object.

/// </returns>

protected override DataControlField CreateField()

{

    return new ExtendedImageField();

}

/// <summary>

/// Adds text or controls to a cell's controls collection.

/// </summary>

/// <param name="cell">A <see cref="T:System.Web.UI.WebControls.DataControlFieldCell"/> that contains the text or controls of the <see cref="T:System.Web.UI.WebControls.DataControlField"/>.</param>

/// <param name="cellType">One of the <see cref="T:System.Web.UI.WebControls.DataControlCellType"/> values.</param>

/// <param name="rowState">One of the <see cref="T:System.Web.UI.WebControls.DataControlRowState"/> values, specifying the state of the row that contains the <see cref="T:System.Web.UI.WebControls.DataControlFieldCell"/>.</param>

/// <param name="rowIndex">The index of the row that the <see cref="T:System.Web.UI.WebControls.DataControlFieldCell"/> is contained in.</param>

public override void InitializeCell(DataControlFieldCell cell, DataControlCellType cellType, DataControlRowState rowState, int rowIndex)

{

    base.InitializeCell(cell, cellType, rowState, rowIndex);

    if (cellType == DataControlCellType.DataCell)

    {

        cell.DataBinding += new EventHandler(OnBindingField);

    }

}

/// <summary>

/// Called when [binding field].

/// </summary>

/// <param name="sender">The sender.</param>

/// <param name="e">The <see cref="System.EventArgs"/> instance containing the event data.</param>

private void OnBindingField(object sender, EventArgs e)

{

    Control target = (Control)sender;

    TableCell tCell = target as TableCell;

    if (tCell != null)

    {

        tCell.Attributes.Add("valign", "center");

        object dataItem = DataBinder.GetDataItem(target.NamingContainer);

        string _tooltipText = (string)DataBinder.GetPropertyValue(dataItem, _propertyName);

        if (!String.IsNullOrEmpty(_tooltipText))

        {

            Image image = new Image();

            image.ImageUrl = _imageUrl;

            image.ToolTip = _tooltipText;

            target.Controls.Add(image);

        }

    }

}

protected void Page_Load(object sender, EventArgs e)

    {

        if (!Page.IsPostBack)

        {

            User user = new User();

            string _userid = Request.QueryString["userid"];

            using (SqlConnection conexion = new SqlConnection(""))

            {

                conexion.Open();

                ///Pruebas SQL Injection CAT.NET

                SqlCommand comando = new SqlCommand();

                comando.CommandText = "SELECT Name, Surname FROM Users WHERE Id = '" + _userid + "'";

                comando.Connection = conexion;

                IDataReader reader = comando.ExecuteReader();

                if (reader.Read())

                {

                    user.Id = _userid;

                    user.Name = reader.GetString(0);

                    user.Surname = reader.GetString(1);

                }

            }

        }

    }

public void ProcessRequest(HttpContext context)

    {

        if (!string.IsNullOrEmpty(context.Request.QueryString["file"]))

        {

            string fileName = context.Request.QueryString["file"];

            string folder = "/files/";

            if (System.IO.File.Exists(context.Server.MapPath(folder) + fileName))

            {

                context.Response.AppendHeader("Content-Disposition", "attachment; filename=" + context.Server.UrlEncode(fileName));

                context.Response.Cache.SetCacheability(HttpCacheability.NoCache);

                context.Server.Transfer(folder + fileName, false);

            }

            else

            {

                context.Response.Status = "404 Bad Request";

            }

        }

    } 

   public class ExtendedWorkLoadToolPart : ToolPart

protected override void CreateChildControls()

{

    base.CreateChildControls();

    /// Añadir nuestros controles  

}

/// <summary>

/// Sends the tool part content to the specified HtmlTextWriter object, 

/// which writes the content to be rendered on the client.

/// </summary>

/// <param name="output">The HtmlTextWriter object that receives the tool part content.</param>

protected override void RenderToolPart(System.Web.UI.HtmlTextWriter output)

{

    // Establish a reference to the Web Part.

    WorkLoadWebPart workLoadWebPart =

        (WorkLoadWebPart)this.ParentToolPane.SelectedWebPart;

    output.Write("<table width=\"100%\" cellspacing=\"0\" cellpadding=\"2\"><tr><td colspan=\"2\">");

    _lblDataHeader.Text = SPUtility.GetLocalizedString("$Resources:webpart_lblDataHeader_text", "company", SPContext.Current.Web.Language);

    _lblDataHeader.Font.Bold = true;

    _lblDataHeader.RenderControl(output);

    output.Write("<hr></td></tr><tr><td>");

    _lblObjectType.Text = SPUtility.GetLocalizedString("$Resources:webpart_lblObjectType_text", "company", SPContext.Current.Web.Language);

    _lblObjectType.RenderControl(output);

    output.Write("</td><td>");

    _ddlObjectType.SelectedValue = Enum.GetName(typeof(EnumObjectType), workLoadWebPart.TipoObjeto);

    _ddlObjectType.RenderControl(output);

    output.Write("</td></tr><tr><td>");

    _lblActiveUser.Text = SPUtility.GetLocalizedString("$Resources:webpart_lblActiveUser_text", "company", SPContext.Current.Web.Language);

    _lblActiveUser.RenderControl(output);

    output.Write("</td><td>");

    _chkActiveUser.Checked = workLoadWebPart.UsuarioActivo;

    _chkActiveUser.RenderControl(output);

    output.Write("</td></tr><tr><td>");

    _lblDelimerChar.Text = SPUtility.GetLocalizedString("$Resources:webpart_lblDelimerChar_text", "company", SPContext.Current.Web.Language);

    _lblDelimerChar.RenderControl(output);

    output.Write("</td><td>");

    _txtDelimiterChar.Text = workLoadWebPart.DelimitadorUsurios.ToString();

    _txtDelimiterChar.RenderControl(output);

    output.Write("</td></tr><tr><td colspan=\"2\">");

    _lblVariosHeader.Text = SPUtility.GetLocalizedString("$Resources:webpart_lblVariosHeader_text", "company", SPContext.Current.Web.Language);

    _lblVariosHeader.Font.Bold = true;

    _lblVariosHeader.RenderControl(output);

    output.Write("<hr></td></tr><tr><td>");

    _lblBarType.Text = SPUtility.GetLocalizedString("$Resources:webpart_lblBarType_text", "company", SPContext.Current.Web.Language);

    _lblBarType.RenderControl(output);

    output.Write("</td><td>");

    _ddlBarType.SelectedValue = Enum.GetName(typeof(EnumBarType), workLoadWebPart.TipoBarra);

    _ddlBarType.RenderControl(output);

    output.Write("</td></tr><tr><td>");

    _lblShowLabels.Text = SPUtility.GetLocalizedString("$Resources:webpart_lblShowLabels_text", "company", SPContext.Current.Web.Language);

    _lblShowLabels.RenderControl(output);

    output.Write("</td><td>");

    _chkShowLabels.Checked = workLoadWebPart.MostrarEtiquetas;

    _chkShowLabels.RenderControl(output);

    output.Write("</td></tr><tr><td>");

    _lblPlacePecentage.Text = SPUtility.GetLocalizedString("$Resources:webpart_lblPlacePecentage_text", "company", SPContext.Current.Web.Language);

    _lblPlacePecentage.RenderControl(output);

    output.Write("</td><td>");

    _ddlPlacePercentage.SelectedValue = Enum.GetName(typeof(EnumPlacePercentage), workLoadWebPart.UbicacionPorcentaje);

    _ddlPlacePercentage.RenderControl(output);

    output.Write("</td></tr><tr><td>");

    output.Write("</td></tr><tr><td colspan=\"2\">");

    _lblSecurityHeader.Text = SPUtility.GetLocalizedString("$Resources:webpart_lblSecurityHeader_text", "company", SPContext.Current.Web.Language);

    _lblSecurityHeader.Font.Bold = true;

    _lblSecurityHeader.RenderControl(output);

    output.Write("<hr></td></tr><tr><td>");

    _lblProfiles.Text = SPUtility.GetLocalizedString("$Resources:webpart_lblProfiles_text", "company", SPContext.Current.Web.Language);

    _lblProfiles.RenderControl(output);

    output.Write("</td><td>");

    _ddlProfiles.SelectedValue = workLoadWebPart.PerfilPermitido;

    _ddlProfiles.RenderControl(output);

    output.Write("</td></tr></table>");

}

// Establish a reference to the Web Part.

WorkLoadWebPart customWebPartEx1 =

        (WorkLoadWebPart)this.ParentToolPane.SelectedWebPart;

/// <summary>

/// Called when the user clicks the OK or the Apply button in the tool pane.

/// </summary>

public override void ApplyChanges()

{

    // Establish a reference to the Web Part.

    WorkLoadWebPart workLoadWebPart =

        (WorkLoadWebPart)this.ParentToolPane.SelectedWebPart;

    workLoadWebPart.UbicacionPorcentaje = (EnumPlacePercentage)Enum.Parse(typeof(EnumPlacePercentage), _ddlPlacePercentage.SelectedValue);

    workLoadWebPart.TipoBarra = (EnumBarType)Enum.Parse(typeof(EnumBarType), _ddlBarType.SelectedValue);

    workLoadWebPart.PerfilPermitido = _ddlProfiles.SelectedValue;

    workLoadWebPart.TipoObjeto = (EnumObjectType)Enum.Parse(typeof(EnumObjectType), _ddlObjectType.SelectedValue);

    workLoadWebPart.MostrarEtiquetas = _chkShowLabels.Checked;

    workLoadWebPart.UsuarioActivo = _chkActiveUser.Checked;

    workLoadWebPart.DelimitadorUsurios = _txtDelimiterChar.Text.ToCharArray()[0];

}

/// <summary>

/// Determines which tool parts are displayed in the tool pane of the Web-based Web Part design user interface, and the order in which they are displayed.

/// </summary>

/// <returns>

/// An array of type <see cref="T:Microsoft.SharePoint.WebPartPages.ToolPart"></see> that determines which tool parts will be displayed in the tool pane. If a Web Part that implements one or more custom properties does not override the <see cref="M:Microsoft.SharePoint.WebPartPages.WebPart.GetToolParts"></see> method, the base class method will return an instance of the <see cref="T:Microsoft.SharePoint.WebPartPages.WebPartToolPart"></see> class and an instance of the <see cref="T:Microsoft.SharePoint.WebPartPages.CustomPropertyToolPart"></see> class. An instance of the <see cref="T:Microsoft.SharePoint.WebPartPages.WebPartToolPart"></see> class displays a tool part for working with the properties provided by the WebPart base class. An instance of the <see cref="T:Microsoft.SharePoint.WebPartPages.CustomPropertyToolPart"></see> class displays a built-in tool part for working custom Web Part properties, as long as the custom property is of one of the types supported by that tool part. The supported types are: String, Boolean, Integer, DateTime, or Enum.

/// </returns>

[SharePointPermission(SecurityAction.Demand, ObjectModel = true)]

public override ToolPart[] GetToolParts()

{

    return new ToolPart[] { new WebPartToolPart(), new ExtendedWorkLoadToolPart() };

}