LinkList Class (C#, ASP.NET)

This class can be used to generate a list of links that could be used for breadcrumbs or menu navigation. Add items to the list as follows (1st parameter is text, 2nd is the page url and 3rd is the tooltip, which is optional):

LinkList links = new LinkList();
links.Add(new LinkList.Link("Home", ResolveUrl("home.aspx"), "Home Page"));
links.Add(new LinkList.Link("Page 1", ResolveUrl("page1.aspx")));
links.Add(new LinkList.Link("Page 2", ResolveUrl("page2.aspx")));
links.Add(new LinkList.Link("Page 3", ResolveUrl("page3.aspx")));
// need to set CssClass for 'Inline' and 'Block' types
links.CssClass = "myclass";

There are four types of list types. Shown in the order they are added in. Also, if the current page you are on is the same as one in the list, the text is displayed instead of the link.

One is 'Inline', which surrounds the links with a span tag (only if you set the CssClass to a non-blank string) and separates the links with whatever you define (the default is the > symbol):

// use inline type (surround with span tags)
links.ListType = LinkList.ListTypes.Inline;
this.Controls.Add(new LiteralControl("<p>Inline ListType</p>"));
this.Controls.Add(new LiteralControl(links.ToString()));

Inline ListType

Home > Page 1 > Page 2 > Page 3

Another is 'Block' (works in same way as 'Inline', but uses a div tag):

// use block type (surround with div tags)
links.ListType = LinkList.ListTypes.Block;
// change separator
links.Separator = " | ";
this.Controls.Add(new LiteralControl("<p>Block ListType</p>"));
this.Controls.Add(new LiteralControl(links.ToString()));

Block ListType

Home | Page 1 | Page 2 | Page 3

Another is 'OrderedList':

// use ordered list type (surround with ol, li tags)
links.ListType = LinkList.ListTypes.OrderedList;
this.Controls.Add(new LiteralControl("<p>OrderedList ListType</p>"));
this.Controls.Add(new LiteralControl(links.ToString()));

OrderedList ListType

  1. Home
  2. Page 1
  3. Page 2
  4. Page 3

Finally 'UnorderedList':

// use unordered list type (surround with ul, li tags)
links.ListType = LinkList.ListTypes.UnorderedList;
this.Controls.Add(new LiteralControl("<p>UnorderedList ListType</p>"));
this.Controls.Add(new LiteralControl(links.ToString()));

UnorderedList ListType

The code that actually does the work is as follows:

using System;
using System.Collections;
using System.Text;
using System.Web;

namespace WebDeveloperBlog
{  
 public class LinkList : CollectionBase
 {
  public class Link
  {
   private string url;
   public string Url
   {
    get
    {
     return url;
    }
    set
    {
     url = value;
    }
   }
   private string text;
   public string Text
   {
    get
    {
     return text;
    }
    set
    {
     text = value;
    }
   }
   private string tooltip;
   public string Tooltip
   {
    get
    {
     return tooltip;
    }
    set
    {
     tooltip = value;
    }
   }
   public Link(string text, string url)
   {
    this.Text = text;
    this.Url = url;
   }
   public Link(string text, string url, string tooltip)
   {
    this.Text = text;
    this.Url = url;
    this.Tooltip = tooltip;
   }
  }
  
  public string cssClass = string.Empty;
  public string CssClass
  {
   get
   {
    return (cssClass);
   }
   set
   {
    this.cssClass = value;
   }
  }
  
  public enum ListTypes
  {
   Inline, Block, OrderedList, UnorderedList
  }
  
  public ListTypes listType = ListTypes.Inline;
  public ListTypes ListType
  {
   get
   {
    return (listType);
   }
   set
   {
    this.listType = value;
   }
  }
  
  public string separator = " > ";
  public string Separator
  {
   get
   {
    return (separator);
   }
   set
   {
    this.separator = value;
   }
  }
  
  public override string ToString()
  {
   StringBuilder sb = new StringBuilder();
   if (ListType == ListTypes.OrderedList)
   {
    sb.Append("<ol");
    if (CssClass != string.Empty)
    {
     sb.Append(" class=\"" + CssClass + "\"");
    }
    sb.Append(">");
   }
   if (ListType == ListTypes.UnorderedList)
   {
    sb.Append("<ul");
    if (CssClass != string.Empty)
    {
     sb.Append(" class=\"" + CssClass + "\"");
    }
    sb.Append(">");
   }
   if (CssClass != string.Empty && ListType == ListTypes.Inline)
   {
    sb.Append("<span class=\"" + CssClass + "\">");
   }
   if (CssClass != string.Empty && ListType == ListTypes.Block)
   {
    sb.Append("<div class=\"" + CssClass + "\">");
   }
   foreach(Link item in this)
   {
    if(this.IndexOf(item)!=0 && (ListType == ListTypes.Inline || ListType == ListTypes.Block))
    {
     sb.Append(HttpContext.Current.Server.HtmlEncode(Separator));
    }
    if (ListType == ListTypes.OrderedList || ListType == ListTypes.UnorderedList)
    {
     sb.Append("<li>");
    }
    if(item.Url != HttpContext.Current.Request.Url.AbsolutePath)
    {
     sb.Append("<a href=\"" + item.Url + "\"");
     if (item.Tooltip != null)
     {
      sb.Append(" title=\"" + item.Tooltip + "\"");
     }
     sb.Append(">" + item.Text + "</a>");
    }
    else
    {
     sb.Append(item.Text);
    }
    if (ListType == ListTypes.OrderedList || ListType == ListTypes.UnorderedList)
    {
     sb.Append("</li>");
    }
   }
   if (CssClass != string.Empty && ListType == ListTypes.Inline)
   {
    sb.Append("</span>");
   }
   if (CssClass != string.Empty && ListType == ListTypes.Block)
   {
    sb.Append("</div>");
   }
   if (ListType == ListTypes.OrderedList)
   {
    sb.Append("</ol>");
   }
   if (ListType == ListTypes.UnorderedList)
   {
    sb.Append("</ul>");
   }
   return sb.ToString();
  }
  
  public Link this[int index]
  {
   get
   {
    return ((Link)(this.List[index]));
   }
   set
   {
    this.List[index] = value;
   }
  }
  
  public int Add(Link value)
  {
   return this.List.Add(value);
  }
  
  public void Insert(int index, Link value)
  {
   this.List.Insert(index, value);
  }
  
  public int IndexOf(Link value)
  {
   return this.List.IndexOf(value);
  }
  
  public bool Contains(Link value)
  {
   return this.List.Contains(value);
  }
  
  public void Remove(Link value)
  {
   this.List.Remove(value);
  }
  
  public void CopyTo(Link[] array, int index)
  {
   this.List.CopyTo(array, index);
  }
 }
}

Tags: , ,

Comments

Post a Comment

Popular posts from this blog

Select box manipulation with jQuery

If you read the jQuery mailing list , you may be aware that I have updated my plugins for working with select boxes . Summary of changes: addOption replaces any options with the same value (so think of it as an add/replace options plugin selectOptions selected options in addition to what was already selected, but there is now an option for it not to do this There are two new methods: copyOptions which is for copying options between select boxes ajaxAddOption allows you to add options via AJAX (i.e. could be used for create options dynamically from a server script)
Read more

iTextSharp: Generating a Basic PDF file (ASP.NET/C#)

iTextSharp is free library for .NET that allows you to create PDF documents. It can be used to dynamically create PDF's which can be streamed to the user. As there is no HTML being sent to the user, a WebHandler (ashx file) is a more appropriate way to generate your PDF than an aspx page. Download itextsharp-3.0.10-dll.zip (latest version as of 08 Feb 2006) and save the dll in the archive to your websites bin directory. Here is a basic sample of creating a PDF (more complex samples may follow in future posts). BasicPDF.ashx <%@ WebHandler Language="C#" Class="MyNamespace.BasicPDF" %> using System; using System.IO; using System.Web; using iTextSharp.text; using iTextSharp.text.pdf; namespace MyNamespace { public class BasicPDF: IHttpHandler { public bool IsReusable { get { return true; } } /// <summary> /// Font used for any hyperlinks added to the PDF /// </summary> private Font LinkFont { get ...
Read more

Popup Window Countdown (JavaScript)

This code opens a new popup window that contains a timer that counts down, then closes the window when it reaches 0. Will not work if user has a popup blocker blocking the page. <html> <head> <title>Popup Timer</title> <script language="JavaScript" type="text/JavaScript"> // popup window var var popup; // At what number shall the countdown counter start? CounterStart = 10; // This function CustomAction() can be modified to do // whatever you want done every second. function CustomAction() { popup.document.timer.timeleft.value = CounterStart; } // end of function CustomAction() // end of JavaScript customization function Decrement() { CounterStart--; CustomAction(); if(CounterStart <= 0) { popup.close(); alert('Timer reached 0'); } else { setTimeout('Decrement()',1000); } } function StartTheCounter() { openPopup(120,100); setTimeout('Decrement()',1000); } f...
Read more