Image control won't show ImageURL

zliminator
zliminator used Ask the Experts™
on
I've got a black image control on my webform and a dropdownlistbox which gives a list of jpg files to choose from.  I step threw it and verify the correct path is being sent to Image1.ImageURL but no picture shows up. I can't find any other properties to set on the Image control. Also, why do I have to make pathx static? When it was private (or public) it got set to null when assigning it to target string.

using System;
using System.Data;
using System.Configuration;
using System.Web;
using System.Web.Security;
using System.Web.UI;
using System.Web.UI.WebControls;
using System.Web.UI.WebControls.WebParts;
using System.Web.UI.HtmlControls;
using System.IO;
using System.Collections;

public partial class _Default : System.Web.UI.Page 
{
    static string pathx;
    protected void Page_Load(object sender, EventArgs e)
    {
        if(!IsPostBack)
        {
            DirectoryInfo dInfo = new DirectoryInfo(Server.MapPath("pics"));
            pathx = dInfo.FullName;
            ArrayList alFiles = new ArrayList();
           
            alFiles.AddRange(dInfo.GetFiles("*.jpg"));

            foreach (FileInfo fInfo in alFiles)
            {
                DropDownList1.Items.Add(fInfo.Name);
            }
        }
    }
   
    protected void DropDownList1_TextChanged(object sender, EventArgs e)
    {
        string x = DropDownList1.SelectedValue;
        string target = pathx;
        target += "\\";
        target += x;
        Image1.ImageUrl = target;
    }
 
}
 

Open in new window

Comment
Watch Question

Do more with

Expert Office
EXPERT OFFICE® is a registered trademark of EXPERTS EXCHANGE®
ǩa̹̼͍̓̂ͪͤͭ̓u͈̳̟͕̬ͩ͂̌͌̾̀ͪf̭̤͉̅̋͛͂̓͛̈m̩̘̱̃e͙̳͊̑̂ͦ̌ͯ̚d͋̋ͧ̑ͯ͛̉Glanced up at my screen and thought I had coded the Matrix...  Turns out, I just fell asleep on the keyboard.
Most Valuable Expert 2011
Top Expert 2015
Commented:
Also, why do I have to make pathx static?
You don't. The only reason why I can think of that it would be "set to null when assigning it to target string" is that the SelectedValue of the DropDownList was null.

Your pathx variable is set to the full local path of the directory for "pics". This is something anyone not on your physical machine (i.e. everyone not sitting at your computer) would have access to. You need to use the "ASP path". That is "pics" by itself. You use the full local path to retrieve the files from disk; you use the "ASP path" to serve up files to your users.

Try changing line 36 to:

string target = "pics";

Open in new window

Software Architect
Top Expert 2008
Commented:
I think this may be a cleaner solution:

protected void DropDownList1_TextChanged(object sender, EventArgs e)
{
    Image1.ImageUrl = ResolveUrl("~/pics/" +DropDownList1.SelectedValue);
}

no need for 'pathx'

Author

Commented:
It works but I need to study that article.

Do more with

Expert Office
Submit tech questions to Ask the Experts™ at any time to receive solutions, advice, and new ideas from leading industry professionals.

Start 7-Day Free Trial