Custom Controls ASP.Net Tutorial

File: Control.ascx
<%@ Control Language="C#" ClassName="PropertyRandomImage" %>
<%@ Import Namespace="System.IO" %>

    private string _imageFolderPath = "~/Images";
    public string ImageFolderPath
    {
        get { return _imageFolderPath; }
        set { _imageFolderPath = value; }
    }
    void Page_Load()
    {
        string imageToDisplay = GetRandomImage();
        imgRandom.ImageUrl = Path.Combine(_imageFolderPath, imageToDisplay);
        lblRandom.Text = imageToDisplay;
    }
    private string GetRandomImage()
    {
        Random rnd = new Random();
        string[] images = Directory.GetFiles(MapPath("~/Images"), "*.jpg");
        string imageToDisplay = images[rnd.Next(images.Length)];
        return Path.GetFileName(imageToDisplay);
    }

    id="imgRandom"
    Width="300px"
    Runat="server" />

    id="lblRandom"
    Runat="server" />
File: ShowDeclarative.aspx
<%@ Page Language="C#" %>
<%@ Register TagPrefix="user" TagName="PropertyRandomImage" Src="~/Control.ascx" %>
"http://www.w3.org/TR/xhtml11/DTD/xhtml11.dtd">


    Show Declarative


    
    

            ID="PropertyRandomImage1"
        ImageFolderPath="~/Images2"
        Runat="server" />