Exposing Properties from a User Control : Introduction « Custom Controls « ASP.NET Tutorial






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  3. Introduction
File: Control.ascx

<%@ Control Language="C#" ClassName="PropertyRandomImage" %>
<%@ Import Namespace="System.IO" %>
<script runat="server">

    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);
    }
</script>

<asp:Image
    id="imgRandom"
    Width="300px"
    Runat="server" />
<br />
<asp:Label
    id="lblRandom"
    Runat="server" />

File: ShowDeclarative.aspx

<%@ Page Language="C#" %>
<%@ Register TagPrefix="user" TagName="PropertyRandomImage" Src="~/Control.ascx" %>
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.1//EN"
"http://www.w3.org/TR/xhtml11/DTD/xhtml11.dtd">
<html xmlns="http://www.w3.org/1999/xhtml" >
<head id="Head1" runat="server">
    <title>Show Declarative</title>
</head>
<body>
    <form id="form1" runat="server">
    <div>

    <user:PropertyRandomImage
        ID="PropertyRandomImage1"
        ImageFolderPath="~/Images2"
        Runat="server" />

    </div>
    </form>
</body>
</html>








14.1.Introduction
14.1.1.Differences between user controls and web pages
14.1.2.Page control with full qualified name(C#)
14.1.3.Get value from asp.net page control (VB.net)
14.1.4.Use properties defined in custom control
14.1.5.Page component with code behind (VB.net)
14.1.6.Exposing Properties from a User Control
14.1.7.Set the properties from user control programmatically.