Linq GetEnumerator.reset and new MS Chart charting controls

So I thought I would try out the new Microsoft charting controls for ASP.Net and winforms...

Looks fantastic but when I came to do some runtime databinding to a simple linq collection (selecting an x and y value into an enumerable anonymous type...) it failed miserably with an obscure error message.

With a bit of snooping I found that the problem is that the chart control always calls .Reset() on its IEnumerable(Of T) datasource before iterating the collection. Unfortunately the System.Linq.Enumerable.Iterator(Of TSource) that Linq returns as a concrete IEnumerable throws a "NotImplementedException" in its implementation of IEnumerable.Reset() - good one MS! (Check it out in Reflector)

Simple answer - call .ToArray() on your Linq collection and hey presto your Linq query will work as a chart datasource.

UPDATE - Click here and vote for MS to fix this bug!!!

Retro Games Released

As a programming "hobby" I have been writing retro 8-bit games - you can play the results here:

http://wiki.cpc-live.com/index.php/Robotron_6128

http://wiki.cpc-live.com/index.php/Sewer_Rat

Credit Services NZ Ltd

An Improved MsgBox for Asp.Net

Often times a simple messagebox is required at the client under ASP.Net. This is easy to do by sending back a JavaScript Alert(). However, this does not work so well if the user navigates around using the back and forward buttons, as they will see the message multiple times. Also, we would like our msgbox to be usable from AJAX enabled apps, so that an asynchronous postback can also trigger an alert.

The below vb.net 3.5 code meets these criteria:

Module PageExtensions

    <extension()> _

    Public Sub MsgBox(ByVal aPage As Page, ByVal aMessage As String)

        Dim timeStr As String = "msgbox" & Date.Now().Ticks.ToString

        ' Set a cookie after showing alert so as will not re-show if back button or refresh is used.

        Dim alertScript As String = "if (document.cookie.indexOf('" & timeStr & "') == -1) {"

        alertScript &= "alert(""" & aMessage & """);"

        alertScript &= "document.cookie = '" & timeStr & "=deleted';}"

        System.Web.UI.ScriptManager.RegisterStartupScript(aPage, GetType(String), aMessage, alertScript, True)

    End Sub

End Module

To use within a page, you can now simply type:

MsgBox("Hello World"), just like in a Windows App.

A temporary cookie is set for each msgbox invoked so that the msgbox will only be shown once. The method is an extension method of the Page class, so needs to be contained within a Module, or used without the attribute.

Note also you will need a reference to System.Web.Extensions in your project.

EazyCaptcha.com Simple Captcha Server

As a programming exercise I created a public captcha server that can be used to generate captchas without requiring any software libraries or complex programming by the developer.

You can try it out here...

www.eazycaptcha.com

VegePlan

VegePlan is a pet .Net project I have been working on to get up to speed on AJAX and LINQ.

It is a basic drag-n-drop vegetable garden planner and designer.

I have openend it up for anyone to use here:

www.vegeplan.com

I have used the JavaScript Prototype library for the AJAX, and YUI and the Ajax Control Toolkit for the drag-n-drop and other UI functionality.

Homebrew Google Position finder for Keywords / Domain

SEO sites like http://www.seomoz.org/rank-checker are great if you want to check out how your page ranks in Google for a given set of keywords, but you can only perform 5 searches per day using the free account :(.
There are others out there that will let you perform lots of searches, but restrict you to the first 100 results.

Apparently Google limits a given user to only so many (1000?) searches per day before having to use a CAPTCHA to perform subsequent searches, which I guess is understandable.

But what if you want to do more than 5 but less than 1000? And you want to scan the first 1000 results, because your site is really crap and you want to see if it's getting better? Luckily ,it is trivial to replicate the behaviour of SEOMOZ using simple screen scraping techniques. If you use the code below and install it on your localhost IIS you will be able to perform (practically) unlimited SEO searches. With the caveat that Google may at their whim change their HTML of course and hence break it!

Use at your own risk would be my advice.

You will need the latest .Net Framework 3.5 to run this. Create a new web app project in Visual Studio Pro 2008 or Web Dev Express and make a new .aspx page. Copy and paste the code below and voila, it should all work! (Oh yeah, you'll need a couple of images too if you want the nice AJAX effect - I suggest http://www.ajaxload.info/) If you are wondering it's Open Source so feel free to make it work better for you!


(Copy all to new .aspx page)

<%@ Import Namespace="System.IO" %>

<%@ Import Namespace="System.Net" %>



<%@ Page Language="vb" AutoEventWireup="false" EnableViewState="false" %>



<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">



<script runat="server">







   Private _baseURL As String = "http://www.google.co.nz/search?num=100"

  

    Protected Sub btnGo_Click(ByVal sender As Object, ByVal e As EventArgs) Handles btnGo.Click

        Dim baseurl As String = _baseURL & "&q=" & Me.txtKeywords.Text.Trim



        Dim numTries As Int32 = Math.Min(CInt(Me.cbxResults.Text) \ 100, 10)





        For iTry As Int32 = 1 To numTries

            Dim url As String = baseurl

            If iTry > 1 Then

                url &= "&start=" & ((iTry - 1) * 100).ToString

            End If



            Dim results As String = Me.readHTMLPage(url)



            If results.ToLower.Contains(Me.txtDomain.Text.Trim.ToLower) Then

                Me.showResults(results, (iTry - 1) * 100, url)

                Return

            End If

        Next



        ' If got here then not found

        Me.lblResult.Text = "Not found..."

        Me.lblResult.Visible = True

    End Sub



    Private Sub showResults(ByVal someHTML As String, ByVal addResults As Int32, ByVal googleURL As String)



        Dim googleResults As New List(Of String)(someHTML.Split(New String() {"<div class=g>", "<div class=g "}, StringSplitOptions.RemoveEmptyEntries))



        If googleResults.Count > 0 Then

            googleResults.RemoveAt(0) ' Remove the header rubbish from google

        End If



        Dim resultNum As Int32 = 1



        For Each aResult As String In googleResults

            If aResult.ToLower.Contains(Me.txtDomain.Text.Trim.ToLower) Then

                Me.lblResult.Text = "Result found at position " & (addResults + resultNum).ToString()

                Me.lblResult.Visible = True



                Dim link As New HyperLink()

                link.NavigateUrl = googleURL

                link.Text = googleURL



                Me.panelResults.Controls.Add(link)

                Me.panelResults.Controls.Add(New LiteralControl("<br /><hr />"))



                ' Show the resulting text

                If aResult.ToLower.Contains("<br clear=""all""/>") Then

                    ' Remove below that

                    aResult = Split(aResult, "<br clear=""all""/>", , CompareMethod.Text)(0)

                End If

                aResult = Replace(aResult, "onmousedown", "onmousedownX") ' Disable on mousedown

                Dim lit As New LiteralControl(aResult)

                Me.panelResults.Controls.Add(lit)

                Return

            End If



            resultNum += 1

        Next



    End Sub



    Private Function readHTMLPage(ByVal url As String) As String

        Dim result As String

        'Threading.Thread.Sleep(3000)



        Dim objRequest As WebRequest = HttpWebRequest.Create(url)



        objRequest.Credentials = CredentialCache.DefaultCredentials



        Dim objResponse As WebResponse = objRequest.GetResponse()



        Using sr As New StreamReader(objResponse.GetResponseStream())

            result = sr.ReadToEnd()



            sr.Close()

        End Using



        Return result



    End Function

</script>



<html xmlns="http://www.w3.org/1999/xhtml" >

<head runat="server">

    <title>Untitled Page</title>

    <style type="text/css">

        .style1

        {

            width: 255px;

        }

        .style2

        {

            font-size: x-large;

        }

    </style>

    <style type="text/css">

        div,td,.n a,.n a:visited{color:#000}.ts td,.tc{padding:0}.ts,.tb{border-collapse:collapse}.ti,.bl{display:inline}.ti{display:inline-table}.f,.m{color:#666}.flc,a.fl{color:#77c}a,.w,.q:visited,.q:active,.q,.b a,.b a:visited,.mblink:visited{color:#00c}a:visited{color:#551a8b}a:active{color:red}.t{background:#d5ddf3;color:#000;padding:5px 1px 4px}.bb{border-bottom:1px solid #36c}.bt{border-top:1px solid #36c}.j{width:34em}.h{color:#36c}.i{color:#a90a08}.a{color:green}.z{display:none}div.n{margin-top:1ex}.n a,.n .i{font-size:10pt}.n .i,.b a{font-weight:bold}.b a{font-size:12pt}.std{font-size:82%}#np,#nn,.nr,#logo span,.ch{cursor:pointer;cursor:hand}.ta{padding:3px 3px 3px 5px}#tpa2,#tpa3{padding-top:9px}#gbar{float:left;height:22px;padding-left:2px}.gbh,.gb2 div{border-top:1px solid #c9d7f1;font-size:0;height:0}.gbh{position:absolute;top:24px;width:100%}.gb2 div{margin:5px}#gbi{background:#fff;border:1px solid;border-color:#c9d7f1 #36c #36c #a2bae7;font-size:13px;top:24px;z-index:1000}#guser{padding-bottom:7px !important}#gbar,#guser{font-size:13px;padding-top:1px !important}@media all{.gb1,.gb3{height:22px;margin-right:.73em;vertical-align:top}.gb2 a,.gb2 b{display:block;padding:.2em .5em}}#gbi,.gb2{display:none;position:absolute;width:8em}.gb2{z-index:1001}#gbar a{color:#00c}.gb2 a,.gb3 a{text-decoration:none}#gbar .gb2 a:hover{background:#36c;color:#fff;display:block}.sl,.r{display:inline;font-weight:normal;margin:0}.sl{font-size:84%}.r{font-size:100%}.e{margin:.75em 0}.m{font-size:84%}.sm{display:block;margin:0;margin-left:40px}.slk td{padding-top:5px;padding-left:40px;vertical-align:top;font-size:84%}.slk div{text-indent:-10px;padding-left:10px}.csb,.n div,#logo span{background:url(/images/nav_logo3.png) no-repeat;height:26px;overflow:hidden}.n .nr{background-position:-60px 0;width:16px}#np{width:44px}#nf{background-position:-26px 0;width:18px}#nc{background-position:-44px 0;width:16px}#nn{margin-right:34px;width:66px}#nl{width:46px}#nn,#nl{background-position:-76px 0}#logo{display:block;height:52px;margin:13px 0 7px;overflow:hidden;position:relative;width:150px}#logo span{background-position:0 -26px;height:100%;left:0;position:absolute;top:0;width:100%}.ss{background:url(/images/nav_logo3.png) no-repeat;background-position:0 -87px;display:block;left:0;overflow:hidden;position:absolute;top:0}.cps{overflow:hidden;height:18px;width:114px}.mbi{display:block;font-size:0;width:12px;height:12px;background-position:-114px -78px;margin-right:2px}.mblink{font-size:100%}body,td,div,.p,a{font-family:arial,sans-serif}.g{margin:1em 0}#sd{font-size:84%;font-weight:bold}#ap{font-size:64%}

</style>

</head>

<body>

    

    <script type="text/javascript" src="script/prototype.js"></script>

    

      

    <form id="form1" runat="server">

    <asp:ScriptManager ID="ScriptManager1" runat="server">

    </asp:ScriptManager>

        <asp:UpdatePanel ID="UpdatePanel1" runat="server">

        <ContentTemplate>

    <div>

        <table style="width: 100%;">

            <tr>

                <td class="style1">

                    Keywords</td>

                <td>

                    <asp:TextBox ID="txtKeywords" runat="server" Width="356px"></asp:TextBox>

                </td>

            </tr>

            <tr>

                <td class="style1">

                    Domain </td>   <td>

                    <asp:TextBox ID="txtDomain" runat="server" Width="358px"></asp:TextBox>

                </td>

            </tr>

            <tr>

                <td class="style1">

                    Results to search</td>

                <td>

                    <asp:DropDownList ID="cbxResults" runat="server">

                        <asp:ListItem>100</asp:ListItem>

                        <asp:ListItem>200</asp:ListItem>

                        <asp:ListItem>300</asp:ListItem>

                        <asp:ListItem>400</asp:ListItem>

                        <asp:ListItem>500</asp:ListItem>

                        <asp:ListItem>600</asp:ListItem>

                        <asp:ListItem>700</asp:ListItem>

                        <asp:ListItem>800</asp:ListItem>

                        <asp:ListItem>900</asp:ListItem>

                        <asp:ListItem>1000</asp:ListItem>

                    </asp:DropDownList>

                </td>

            </tr>

            <tr>

                <td class="style1">

                    <asp:Button ID="btnGo" runat="server" Text="Find page rank"  />

                </td>

                <td>

                    <asp:UpdateProgress

                        ID="UpdateProgress1" runat="server" AssociatedUpdatePanelID="UpdatePanel1" DynamicLayout=true>

                        <ProgressTemplate>

                        <div style="background-image: url('images/bg.jpg'); width: 179px;">

                        <img src="Images/loading.gif" /><span class="style2">Searching..</span>.

                        </div>

                            </ProgressTemplate>

                    </asp:UpdateProgress>

                </td>

            </tr>

        </table>

    </div>

    

    <div id=results>

    

    </div>

    

        <asp:Panel ID="panelResults" runat="server">

            <asp:Label ID="lblResult" runat="server" Text="Label" Visible="False"

                Font-Bold="True" Font-Size="X-Large"></asp:Label>

        </asp:Panel>

        </ContentTemplate>

    </asp:UpdatePanel>

    </form>

</body>

</html>

Online Viewstate Viewer / Decoder for Asp.Net 2.0

I got frustrated trying to find an online viewstate decoder for ASP.Net 2.0(.aspx), so wrote my own. You can use it below. NOTE! this is very basic; if you do something wrong you will get a generic error so make sure you copy the viewstate carefully (Firebug in Firefox makes this easy!).

Also, if you have a large viewstate it will take a while for the Treeview to build as I am just using the MS TreeView control which is very verbose in its HTML output.

Breaking news : World's first (possibly) online hex file viewer written entirely in Javascript!