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  • Create Excel (.XLS and .XLSX) file from C#

    - by mistrmark
    What is the best tool for creating an Excel Spreadsheet with C#. Ideally, I would like open source so I don't have to add any third party dependencies to my code, and I would like to avoid using Excel directly to create the file (using OLE Automation.) The .CSV file solution is easy, and is the current way I am handling this, but I but I would like to control the output formats. EDIT: I am still looking at these to see the best alternative for my solution. Interop will work, but it requires Excel to be on the machine you are using. Also the OLEDB method is intriguing, but may not yield much more than what I can achieve with CSV files. I will look more into the 2003 xml format, but that also puts a Excel 2003 requirement on the file. I am currently looking at a port of the PEAR (PHP library) Excel Writer that will allow some pretty good XLS data and formatting and it is in the Excel_97 compatible format that all modern versions of Excel support. The PEAR Excel Writer is here: PEAR - Excel Writer

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  • C# Prevent ItemChecked event on a ListView from Interering with SubItemClicked?

    - by John M
    I am using a in-place editable listview control for a project. The editable listview adds a 'SubItemClicked' event so that each 'cell' can be edited. lstSD2.SubItemClicked += new ListViewEx.SubItemEventHandler(lstSD2_SubItemClicked); I also have the listview checkboxes enabled with a 'ItemChecked' event. The problem is that once the 'ItemChecked' event is enabled double-clicking on any row fires the 'ItemChecked' event and prevents the 'SubItemClicked' event from firing. Is there a way to enforce the need to actually 'check' the listview checkbox instead of firing whenever the row is double-clicked?

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  • C#: Fill DataGridView From Anonymous Linq Query

    - by mdvaldosta
    // From my form BindingSource bs = new BindingSource(); private void fillStudentGrid() { bs.DataSource = Admin.GetStudents(); dgViewStudents.DataSource = bs; } // From the Admin class public static List<Student> GetStudents() { DojoDBDataContext conn = new DojoDBDataContext(); var query = (from s in conn.Students select new Student { ID = s.ID, FirstName = s.FirstName, LastName = s.LastName, Belt = s.Belt }).ToList(); return query; } I'm trying to fill a datagridview control in Winforms, and I only want a few of the values. The code compiles, but throws a runtime error: Explicit construction of entity type 'DojoManagement.Student' in query is not allowed. Is there a way to get it working in this manner?

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  • Simple Branching and Merging with SVN

    Its a good idea not to do too much work without checking something into source control.  By too much work I mean typically on the order of a couple of hours at most, and certainly its a good practice to check in anything you have before you leave the office for the day.  But what if your changes break the build (on the build server you do have a build server dont you?) or would cause problems for others on your team if they get the latest code?  The solution with Subversion is branching and merging (incidentally, if youre using Microsoft Visual Studio Team System, you can shelve your changes and share shelvesets with others, which accomplishes many of the same things as branching and merging, but is a bit simpler to do). Getting Started Im going to assume you have Subversion installed along with the nearly ubiquitous client, TortoiseSVN.  See my previous post on installing SVN server if you want to get it set up real quick (you can put it on your workstation/laptop just to learn how it works easily enough). Overview When you know you are going to be working on something that you wont be able to check in quickly, its a good idea to start a branch.  Its also perfectly fine to create the branch after-the-fact (have you ever started something thinking it would be an hour and 4 hours later realized you were nowhere near done?).  In any event, the first thing you need to do is create a branch.  A branch is simply a copy of the current trunk (a typical subversion setup has root directories called trunk, tags, and branches its a good idea to keep this and to put your branches in the branches folder).  Once you have a new branch, you need to switch your working copy so that it is bound to your branch.  As you work,  you may want to merge in changes that are happening in the trunk to your branch, and ultimately when you are done youll want to merge your branch back into the trunk.  When done, you can delete your branch (or not, but it may add clutter).  To sum up: Create a new branch Switch your local working copy to the new branch Develop in the branch (commit changes, etc.) Merge changes from trunk into your branch Merge changes from branch into trunk Delete the branch Create a new branch From the root of your repository, right-click and select TortoiseSVN > Branch/tag as shown at right (click to enlarge).  This will bring up the Copy (Branch / Tag) interface.  By default the From WC at URL: should be pointing at the trunk of your repository.  I recommend (after ensuring that you have the latest version) that you choose to make the copy from the HEAD revision in the repository (the first radio button).  In the To URL: textbox, you should change the URL from /trunk to /branches/NAME_OF_BRANCH.  You can name the branch anything you like, but its often useful to give it your name (if its just for your use) or some useful information (such as a datestamp or a bug/issue ID from that it relates to, or perhaps just the name of the feature you are adding. When youre done with that, enter in a log message for your new branch.  If you want to immediately switch your local working copy to the new branch/tag, check the box at the bottom of the dialog (Switch working copy to new branch/tag).  You can see an example at right. Assuming everything works, you should very quickly see a window telling you the Copy finished, like the one shown below: Switch Local Working Copy to New Branch If you followed the instructions above and checked the box when you created your branch, you dont need to do this step.  However, if you have a branch that already exists and you would like to switch over to working on it, you can do so by using the Switch command.  Youll find it in the explorer context menu under TortoiseSVN > Switch: This brings up a dialog that shows you your current binding, and lets you enter in a new URL to switch to: In the screenshot above, you can see that Im currently bound to a branch, and so I could switch back to the trunk or to another branch.  If youre not sure what to enter here, you can click the [] next to the URL textbox to explore your repository and find the appropriate root URL to use.  Also, the dropdown will show you URLs that might be a good fit (such as the trunk of the current repository). Develop in the Branch Once you have created a branch and switched your working copy to use it,  you can make changes and Commit them as usual.  Your commits are now going into the branch, so they wont impact other users or the build server that are working off of the trunk (or their own branches).  In theory you can keep on doing this forever, but practically its a good idea to periodically merge the trunk into your branch, and/or keep your branches short-lived and merge them back into the trunk before they get too far out of sync. Merge Changes from Trunk into your Branch Once you have been working in a branch for a little while, change to the trunk will have occurred that youll want to merge into your branch.  Its much safer and easier to integrate changes in small increments than to wait for weeks or months and then try to merge in two very different codebases.  To perform the merge, simply go to the root of your branch working copy and right click, select TortoiseSVN->Merge.  Youll be presented with this dialog: In this case you want to leave the default setting, Merge a range of revisions.  Click Next.  Now choose the URL to merge from.  You should select the trunk of your current repository (which should be in the dropdownlist, or you can click the [] to browse your repository for the correct URL).  You can leave everything else blank since you want to merge everything: Click Next.  Again you can leave the default settings.  If you want to do something more granular than everything in the trunk, you can select a different Merge depth, to include merging just one item in the tree.  You can also perform a Test merge to see what changes will take place before you click Merge (which is often a good idea).  Heres what the dialog should look like before you click Merge: After clicking Merge (or Test merge) you should see a confirmation like this (it will say Test Only in the title if you click Test merge): Now you should build your solution, run all of your tests, and verify that your branch still works the way it should, given the updates that youve just integrated from the trunk.  Once everything works, Commit your changes, and then continue with your work on the branch.  Note that until you commit, nothing has actually changed in your branch on the server.  Other team members who may also be working in this branch wont be impacted, etc.  The Merge is purely a client-side operation until you perform a Commit. In a more real-world scenario, you may have conflicts.  When you do, youll be presented with a dialog like this one: Its up to you which option you want to go with.  The more frequently you Merge, the fewer of these youll have to deal with.  Also, be very sure that youre merging the right folders together.  If you try and merge your trunk with some subfolder in your branchs structure, youll end up with all kinds of conflicts and problems.  Fortunately, theyre only on your working copy (unless you commit them!) but if you see something like that, be sure to doublecheck your URL and your local file location. Merge Your Branch Back Into Trunk When youre done working in your branch, its time to pull it back into the trunk.  The first thing you should do is follow the previous steps instructions for merging the latest from the trunk into your branch.  This lets you ensure that what you have in your branch works correctly with the current trunk.  Once youve done that and committed your changes to your branch, youre ready to proceed with this step. Once youre confident your branch is good to go, you should go to its root folder and select TortoiseSVN->Merge (as above) from the explorer right-click menu.  This time, select Reintegrate a branch as shown below: Click Next.  Youll want it to merge with the trunk, which should be the default: Click Next. Leave the default settings: Click Test merge to see a test, and then if all looks good, click Merge.  Note that if you havent checked in your working copy changes, youll see something like this: If on the other hand things are successful: After this step, its likely you are finished working in your branch.  Dont forget to use the ToroiseSVN->Switch command to change your working copy back to the trunk. Delete the Branch You dont have to delete the branch, but over time your branches area of your repository will get cluttered, and in any event if theyre not actively being worked on the branches are just taking up space and adding to later confusion.  Keeping your branches limited to things youre actively working on is simply a good habit to get into, just like making sure your codebase itself remains tidy and not filled with old commented out bits of code. To delete the branch after youre finished with it, the simplest thing to do is choose TortoiseSVN->Repo Browser.  From there, assuming you did this from your branch, it should already be highlighted.  In any event, navigate to your branch in the treeview on the left, and then right-click and select Delete.  Enter a log message if youd like: Click OK, and its gone.  Dont be too afraid of this, though.  You can still get to the files by viewing the log for branches, and selecting a previous revision (anything before the delete action): If for some reason you needed something that was previously in this branch, you could easily get back to any changeset you checked in, so you should have absolutely no fear when it comes to deleting branches youre done with.   Resources If youre using Eclipse, theres a nice write-up of the steps required by Zach Cox that I found helpful here. Did you know that DotNetSlackers also publishes .net articles written by top known .net Authors? We already have over 80 articles in several categories including Silverlight. Take a look: here.

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  • Cannot open xls file in IE

    - by Vladimir Bezugliy
    We have JSF web application that generates XLS file and gives user link to thes file. All works fine if access this file via HTTP. But IE(8) cannot open/save this xls file via HTTPS. There is following error message: Internet Explorer cannot download ...466088C5C313F92808BDB0AFF3447 from testhost. Internet Explorer was not able to open this Internet site. The requested site is either unavailable or cannot be found. Please try again later. I can open the same document via HTTPS in Firefox and in Chrome. What can be the problem with IE? Headers: HTTP/1.1 200 OK Date: Fri, 18 Jun 2010 14:45:42 GMT Server: Apache-Coyote/1.1 X-Powered-By: Servlet 2.5; JBoss-5.0/JBossWeb-2.1 X-UA-Compatible: IE=EmulateIE7 Last-Modified: Fri, 18 Jun 2010 14:45:11 GMT Cache-control: max-age=0, no-store, no-cache Pragma: no-cache Expires: 0 Content-Type: application/vnd.ms-excel Content-Length: 6656 Keep-Alive: timeout=5, max=100 Connection: Keep-Alive

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  • MDI WinForm application and duplicate child form memory leak

    - by Steve
    This is a WinForm MDI application problem (.net framework 3.0). It will be described in C#. Sorry it is a bit long because I try to make things as clear as possible. I have a MDI application. At some point I find that one MDI child form is never released. There is a menu that creates the MDI child form and show it. When the MDI child form is closed, it is supposed to be destroyed and the memory taken by it should be given back to .net. But to my surprise, this is not true. All the MDI child form instances are kept in memory. This is obviously a "memory leak". Well, it is not a real leak in .net. It is just that I think the closed form should be dead but somehow there is at least one unknown reference from outside world that still connect with the closed form. I read some articles on the Web. Some says that when the MDI child form is closing, I should unwire all the event handlers, otherwise some event handlers may keep my form alive. Some says that DataBindings should be cleaned before the form is closing otherwise the DataBindings will add references to some global Hashtable and thus keep my form alive. My form contains quite a lot things. Many event handlers and many DataBindings and many BindingSources and few suspected controls containing user control and HelpProvider. I create a big method that unwires all the event handlers from all the relevant controls, clear all the DataBindings and DataSources. The HelpProvider and user controls are disposed carefully. At the end, I find that, I don't have to clear DataBindings and DataSources. Event handlers are definitely causing the problem. And MDI form structure also contributes to something. During my experiments, I find that, if you create a MDI child form, even if you close it, there will still be one instance in the memory. The reference is from PropertyStore of the main form. This means, unless the main form is closed (application ends), there will always be one instance of MDI child form in the memory. The good news is that, no matter how many times you open and close the child form, there will be only one instance, not a big "leak". When it comes to event handlers, things become more tricky. I have to address that, all the event handlers on my form are anonymous event handlers. Here is an example code: //On MDI child form's design code... Button btnSave = new Button(); btnSave.Click += new System.EventHandler(btnSave_Click); Where btnSave_Click is also a method in MDI child form. The above is always the case for various controls and various types of event. To me, this is a bi-directional circular reference. btnSave keeps a reference of MDI child form via the event handler. MDI child form keeps a reference of btnSave instance. To me again, such bi-directional circular reference should not cause any problem for .net's garbage collector. This means that I do not have to explicitly unwire the event when the form is being disposed: btnSave.Click -= btnSave_Click; But the truth is not so. For some event handlers, they are safe. Ignoring them do not cause any duplicate instance. For some other event handlers, they will cause one instance remaining in the memory (similar effect as the MDI form structure, but this time caused by the hanging event handlers). For some other event handlers, they will cause every instance opened in the memory. I am totally confused about the differences between these three types of event handlers. The controls are created in the same way and the event is attached in the same way. What is the difference? (Don't tell me it is the event handle methods that make difference.) Anyone has experience of this wired scenario and has an answer for me? Thanks a lot. So now, for safety issue, I will have to unwire all the event handlers when the form is being disposed. That will be a long list of similar code for each control. Is there a general way of removing events from controls in recursive way using reflection? What about performance issue? That's the end of my story and I am still in the middle of my problem. For any help, I thank you.

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  • WebClient vs. HttpWebRequest/HttpWebResponse

    - by Dan
    It seems to me that most of what can be accomplished with HttpWebRequest/Response can also be accomplished with the WebClient class. I read somewhere that WebClient is a high-level wrapper for WebRequest/Response. So far, I can't see anything that can be accomplished with HttpWebRequest/Response that can not be accomplished with WebClient, nor where HttpWebRequest/Response will give you more "fine-grained" control. When should I use WebClient and when HttpWebRequest/Response? (Obviously, HttpWebRequest/Response are HTTP specific.) If HttpWebRequest/Response are lower level then WebClient, what can I accomplish with HttpWebRequest/Response that I cannot accomplish with WebClient?

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  • Is there a way to mark up code to tell ReSharper not to format it?

    - by adrianbanks
    I quite often use the ReSharper "Clean Up Code" command to format my code to our coding style before checking it into source control. This works well in general, but some bits of code are better formatted manually (eg. because of the indenting rules in ReSharper, things like chained linq methods or multi-line ternary operators have a strange indent that pushes them way to the right). Is there any way to mark up parts of a file to tell ReSharper not to format that area? I'm hoping for some kind of markup similar to how ReSharper suppresses other warnings/features. If not, is there some way of changing a combination of settings to get ReSharper to format the indenting correctly? EDIT: I have found this post from the ReSharper forums that says that generated code sections (as defined in the ReSharper options page) are ignored in code cleanup. Having tried it though, it doesn't seem to get ignored.

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  • MSHTML - Auto Click for javascript confirm dialog

    - by Soliton
    I try to automatically parse/submit web page using MSHTML (in C#.Net 3.1 WPF WebBrowser control). I can fill the forms, click buttons, naviagate pages without problems. But do not know how to automatically click "ok" button on javascript confirmation dialog which appear when I click "Submit" button. C# code: mshtml.IHTMLDocument2 doc = (mshtml.IHTMLDocument2)webBrowser.Document; mshtml.IHTMLFormElement form = doc.forms.item("inputForm", 0) as mshtml.IHTMLFormElement; mshtml.IHTMLElement btnSubmit = form.item("btnFormSubmit", null) as mshtml.IHTMLElement; btnSubmit.click(); The confirmation dialog ("Are you sure?" appears. I want somehow to send "Enter" keystroke to MSHTML document to automatically confirm the submission.

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  • Can I prevent window.onbeforeunload from being called when doing an AJAX call

    - by Paul
    I have an AJAX-based grid control. We hook into the window.onbeforeunload event to check if they have unsaved data and if so present them with a message "Are you sure you want to navigate away...you have unsaved data...". All this is good. But AJAX calls also trigger window.onbeforeunload and so if the grid has unsaved data and we make an AJAX call (such as to delete a row in another grid) the user gets the "Are you sure you want to navigate away...you have unsaved data..." message which is not good. Is it possible to suppress the onbeforeunload event for AJAX calls? Or is it possible to detect that a call is an AJAX call? Otherwise we'll have to get hacking! Thanks

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  • Joomla "online-order" component for Joomla

    - by mIRU
    Hello Word :) Somebody can help me in finding an "online - ordering" component for joomla . That can contain the following function : Possibility of creating Form with pages like RS!Form Uploading Files Supporting Payment Gateways like PayPal , MasterCard , WebMoney , YandexMoney ,Money Bookers , Google Checkout ... more ) Saving data in database. A friendly control panel where admin can check statistics , income and expenditure, including offline transactions, and report on the data . A good example , for what I'm looking , is this component http://www.nbill.co.uk/ , but is to expensive and complicated . I'll be happy fore some links or advices :) . Thank a Lot ! for all who are trying to help me ! And sorry for my bad English :-)

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  • Best aproach for multi-page WPF application

    - by 0xDEAD BEEF
    How do i create multislide application in WPF? What is beast approach? What i need is something very similar to having tabcontrol with multiple pages and navigation buttons bellow, but i dont think that tab control is best for this task. I would like to have each view to be in seperate .xaml + class file. AND- it would be cool to have some animiation, when navigating to another page (like old page slides away or something like that. What would be best technique to achieve this?

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  • Where does Internet Explorer store saved passwords?

    - by Ian Boyd
    Where does Internet Explorer store saved passwords? And since this is a programming site, i'm not literally asking for the location where IE stores passwords, but which API ie uses to save passwords. At first i assumed that Microsoft was using the standard api: CredRead CredWrite which is used to save domain and generic program/web-site credentials. CredRead/CredWrite turn around and use CryptProtectData CryptUnprotectData to encrypt data with the current user's account. CredRead/CredWrite then store the data in some magical location, which contents you can see from the control panel: But i don't see IE passwords in there. So ie doesn't store passwords using CredRead/CredWrite. What api does IE use to store passwords, and if it uses CryptProtectData, where does it then store the protected data?

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  • Installing a configuration profile on iPhone - programmatically

    - by Seva Alekseyev
    Hi all, I would like to ship a configuration profile with my iPhone application, and install it if needed. Mind you, we're talking about a configuration profile, not a provisioning profile. First off, such a task is possible. If you place a config profile on a Web page and click on it from Safari, it will get installed. If you e-mail a profile and click the attachment, it will install as well. "Installed" in this case means "The installation UI is invoked" - but I could not even get that far. So I was working under the theory that initiating a profile installation involves navigating to it as a URL. I added the profile to my app bundle. A) First, I tried [sharedApp openURL] with the file:// URL into my bundle. No such luck - nothing happens. B) I then added an HTML page to my bundle that has a link to the profile, and loaded it into a UIWebView. Clicking on the link does nothing. Loading an identical page from a Web server in Safari, however, works fine - the link is clickable, the profile installs. I provided a UIWebViewDelegate, answering YES to every navigation request - no difference. C) Then I tried to load the same Web page from my bundle in Safari (using [sharedApp openURL] - nothing happens. I guess, Safari cannot see files inside my app bundle. D) Uploading the page and the profile on a Web server is doable, but a pain on the organizational level, not to mention an extra source of failures (what if no 3G coverage? etc.). So my big question is: how do I install a profile programmatically? And the little questions are: what can make a link non-clickable within a UIWebView? Is it possible to load a file:// URL from my bundle in Safari? If not, is there a local location on iPhone where I can place files and Safari can find them? EDIT on B): the problem is somehow in the fact that we're linking to a profile. I renamed it from .mobileconfig to .xml ('cause it's really XML), altered the link. And the link worked in my UIWebView. Renamed it back - same stuff. It looks as if UIWebView is reluctant to do application-wide stuff - since installation of the profile closes the app. I tried telling it that it's OK - by means of UIWebViewDelegate - but that did not convince. Same behavior for mailto: URLs within UIWebView. For mailto: URLs the common technique is to translate them into [openURL] calls, but that doesn't quite work for my case, see scenario A. For itms: URLs, however, UIWebView works as expected... EDIT2: tried feeding a data URL to Safari via [openURL] - does not work, see here: http://stackoverflow.com/questions/641461/iphone-open-data-url-in-safari EDIT3: found a lot of info on how Safari does not support file:// URLs. UIWebView, however, very much does. Also, Safari on the simulator open them just fine. The latter bit is the most frustrating.

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  • two different version of AjaxControlToolkit in same web application

    - by shailesh
    I have two different version of AjaxControlToolkit dll and I have added reference of both dll in my web application. I also set up control tagprefix in web.config. Now one of the page is using 1.0 version and I want to use 3.0 version in another page. I am getting following error. "The server tag 'ajaxToolkit:SliderExtender' is ambiguous. Please modify the associated registration that is causing ambiguity and pick a new tag prefix." Any idea where I am doing wrong?

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  • custom events in child userControls c# .net or Child to Parent Communication in UserControls

    - by Asad Malik
    Okay here is the scenario: I have a parent "SalesUC" UserControl which contains a "itemDetailsUC" UserControl, as well as a status label. (plz see sample below) What I want: If there occurs any exception in itemDetailsUC, it should be able to communicate the exception text to parent control (i.e. SalesUC). Remember: the "ItemDetailsUC" is also used in other controls that may or may not have status label. any suggestions, answers... please. Framework: .net 3.0/3.5 Language: c# Domain: Windows Application, WinForms, etc. Sample ScreenShot regards.

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  • JavaScript and CSS files for ASP.NET MVC 2 EditorTemplate user controls

    - by Zack Peterson
    I'm using an EditorTemplate DateTime.ascx in my ASP.NET MVC 2 project. <%@ Control Language="C#" Inherits="System.Web.Mvc.ViewUserControl<DateTime>" %> <%: Html.TextBox(String.Empty, Model.ToString("M/dd/yyyy h:mm tt")) %> <script type="text/javascript"> $(function () { $('#<%: ViewData.TemplateInfo.GetFullHtmlFieldId(String.Empty) %>').AnyTime_picker({ format: "%c/%d/%Y %l:%i %p" }); }); </script> This uses the Any+Time™ JavaScript library for jQuery by Andrew M. Andrews III. I've added those library files (anytimec.js and anytimec.css) to the <head> section of my master page. Rather than include these JavaScript and Cascading Style Sheet files on every page of my web site, how can I instead include the .js and .css files only on pages that need them--pages that edit a DateTime type value?

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  • Hitting the Done button does not dismiss the View of a MPMoviePlayerController on OS 4.0 beta

    - by Hakim
    Hi All Hope someone can help me on this, on the old OS version 3.0 and down , hitting the done button one playing a Video would automatically dismiss the view, but now since we have to control the view appearance, hitting the Done just stops the movie but does not dismiss the view, I tried to check if it was linked to any notification and found that each time the Done button was hit, MPMoviePlayerPlaybackStateDidChangeNotification is triggered the problem is that the same notification is received for any change of state pausing /playing... so dismissing the view when MPMoviePlayerPlaybackStateDidChangeNotification is triggered is not an option. does anyone have an answer for this problem Thx for your help

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  • ASP.NET MVC2 and AJAX

    - by Jason
    I am currently developing a new website utilizing ASP.NET MVC2. Much of what I want to do with the website (from a front-end standpoint) involves AJAX-y-type tasks. Two examples: I want to display forms, and switch between them via a drop-down menu (or through links) without having to go back and hit the server every single time. I want the user to be able to select points on a Chart Control and have portions of the page refresh with the appropriate data depending on what he/she selects (partial page refresh). In both these cases, I am able to accomplish what I wish to accomplish using the traditional web forms event handlers, etc. Unfortunately, the use of a ScriptManager violates the spirit of MVC. It seems as if MVC prevents the use of many of the controls that are available to ASP.NET. So, my question is: how do I use AJAX and make AJAX calls without utilizing ScriptManager and the web forms method of utilizing event handlers?

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  • How to use JQuery UI datepicker with bgIframe on IE 6

    - by Steve Davies
    I am trying to use the JQuery UI datepicker (latest stable version 1.5.2) on an IE6 website. But I am having the usual problems with combo boxes (selects) on IE6 where they float above other controls. I have tried adding the bgIframe plugin after declaring the datepicker with no luck. My guess is that the .ui-datepicker-div to which I am attaching the bgIframe doesn't exist until the calendar is shown. I am wondering if I can put the .bgIframe() command directly into the datepicker .js file and if so, where? (the similar control by kelvin Luck uses this approach) Current code $(".DateItem").datepicker({ showOn:"button", ... etc ... }); $(".ui-datepicker-div").bgIframe();

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  • SendMessage vs. WndProc

    - by Poma
    I'm trying to extend TextBox control to add watermarking functionality. The example I've found on CodeProject is using imported SendMessage function. [DllImport("user32.dll", CharSet = CharSet.Auto, SetLastError = false)] static extern IntPtr SendMessage(IntPtr hWnd, uint Msg, uint wParam, [MarshalAs(UnmanagedType.LPWStr)] string lParam); void SetWatermark() { SendMessage(this.Handle, 0x1501, 0, "Sample"); } I'm wondering why not use protected WndProc instead void SetWatermark() { var m =new Message() { HWnd = this.Handle, Msg = 0x1501, WParam = (IntPtr)0, LParam = Marshal.StringToHGlobalUni("Sample") }; WndProc(ref m); } Both seem to work fine. Almost all examples I've seen on internet use SendMessagefunction. Why is that? Isn't WndProc function designed to replace SendMessage? P.S. I don't know right to convert string to IntPtr and found that Marshal.StringToHGlobalUni works ok. Is it right function to do this?

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  • Include weather information in ASP.Net site from weather.com services

    - by sreejukg
    In this article, I am going to demonstrate how you can use the XMLOAP services (referred as XOAP from here onwards) provided by weather.com to display the weather information in your website. The XOAP services are available to be used for free of charge, provided you are comply with requirements from weather.com. I am writing this article from a technical point of view. If you are planning to use weather.com XOAP services in your application, please refer to the terms and conditions from weather.com website. In order to start using the XOAP services, you need to sign up the XOAP datafeed. The signing process is simple, you simply browse the url http://www.weather.com/services/xmloap.html. The URL looks similar to the following. Click on the sign up button, you will reach the registration page. Here you need to specify the site name you need to use this feed for. The form looks similar to the following. Once you fill all the mandatory information, click on save and continue button. That’s it. The registration is over. You will receive an email that contains your partner id, license key and SDK. The SDK available in a zipped format, contains the terms of use and documentation about the services available. Other than this the SDK includes the logos and icons required to display the weather information. As per the SDK, currently there are 2 types of information available through XOAP. These services are Current Conditions for over 30,000 U.S. and over 7,900 international Location IDs Updated at least Hourly Five-Day Forecast (today + 4 additional forecast days in consecutive order beginning with tomorrow) for over 30,000 U.S. and over 7,900 international Location IDs Updated at least Three Times Daily The SDK provides detailed information about the fields included in response of each service. Additionally there is a refresh rate that you need to comply with. As per the SDK, the refresh rate means the following “Refresh Rate” shall mean the maximum frequency with which you may call the XML Feed for a given LocID requesting a data set for that LocID. During the time period in between refresh periods the data must be cached by you either in the memory on your servers or in Your Desktop Application. About the Services Weather.com will provide you with access to the XML Feed over the Internet through the hostname xoap.weather.com. The weather data from the XML feed must be requested for a specific location. So you need a location ID (LOC ID). The XML feed work with 2 types of location IDs. First one is with City Identifiers and second one is using 5 Digit US postal codes. If you do not know your location ID, don’t worry, there is a location id search service available for you to retrieve the location id from city name. Since I am a resident in the Kingdom of Bahrain, I am going to retrieve the weather information for Manama(the capital of Bahrain) . In order to get the location ID for Manama, type the following URL in your address bar. http://xoap.weather.com/search/search?where=manama I got the following XML output. <?xml version="1.0" encoding="UTF-8"?> <!-- This document is intended only for use by authorized licensees of The –> <!-- Weather Channel. Unauthorized use is prohibited. Copyright 1995-2011, –> <!-- The Weather Channel Interactive, Inc. All Rights Reserved. –> <search ver="3.0">       <loc id="BAXX0001" type="1">Al Manama, Bahrain</loc> </search> You can try this with any city name, if the city is available, it will return the location id, and otherwise, it will return nothing. In order to get the weather information, from XOAP,  you need to pass certain parameters to the XOAP service. A brief about the parameters are as follows. Please refer SDK for more details. Parameter name Possible Value cc Optional, if you include this, the current condition will be returned. Value can be anything, as it will be ignored e.g. cc=* dayf If you want the forecast for 5 days, specify dayf=5 This is optional iink Value should be XOAP par Your partner id. You can find this in your registration email from weather.com prod Value should be XOAP key The license key assigned to you. This will be available in the registration email unit s or m (standard or matric or you can think of Celsius/Fahrenheit) this is optional field, if not specified the unit will be standard(s) The URL host for the XOAP service is http://xoap.weather.com. So for my purpose, I need the following request to be made to access the XOAP services. http://xoap.weather.com/weather/local/BAXX0001?cc=*&link=xoap&prod=xoap&par=*********&key=************** (The ***** to be replaced with the corresponding alternatives) The response XML have a root element “weather”. Under the root element, it has the following sections <head> - the meta data information about the weather results returned. <loc> - the location data block that provides, the information about the location for which the wheather data is retrieved. <lnks> - the 4 promotional links you need to place along with the weather display. Additional to these 4 links, there should be another link with weather channel logo to the home page of weather.com. <cc> - the current condition data. This element will be there only if you specify the cc element in the request. <dayf> - the forcast data as you specified. This element will be there only if you specify the dayf in the request. In this walkthrough, I am going to capture the weather information for Manama (Location ID: BAXX0001). You need 2 applications to display weather information in your website. A Console application that retrieves data from the XMLOAP and store in the SQL Server database (or any data store as you prefer).This application will be scheduled to execute in every 25 minutes using windows task scheduler, so that we can comply with the refresh rate. A web application that display data from the SQL Server database Retrieve the Weather from XOAP I have created a console application named, Weather Service. I created a SQL server database, with the following columns. I named the table as tblweather. You are free to choose any name. Column name Description lastUpdated Datetime, this is the last time when the weather data is updated. This is the time of the service running TemparatureDateTime The date and time returned by XML feed Temparature The temperature returned by the XML feed. TemparatureUnit The unit of the temperature returned by the XML feed iconId The id of the icon to be used. Currently 48 icons from 0 to 47 are available. WeatherDescription The Weather Description Phrase returned by the feed. Link1url The url to the first promo link Link1Text The text for the first promo link Link2url The url to the second promo link Link2Text The text for the second promo link Link3url The url to the third promo link Link3Text The text for the third promo link Link4url The url to the fourth promo link Link4Text The text for the fourth promo link Every time when the service runs, the application will update the database columns from the XOAP data feed. When the application starts, It is going to get the data as XML from the url. This demonstration uses LINQ to extract the necessary data from the fetched XML. The following are the code segment for extracting data from the weather XML using LINQ. // first, create an instance of the XDocument class with the XOAP URL. replace **** with the corresponding values. XDocument weather = XDocument.Load("http://xoap.weather.com/weather/local/BAXX0001?cc=*&link=xoap&prod=xoap&par=***********&key=c*********"); // construct a query using LINQ var feedResult = from item in weather.Descendants() select new { unit = item.Element("head").Element("ut").Value, temp = item.Element("cc").Element("tmp").Value, tempDate = item.Element("cc").Element("lsup").Value, iconId = item.Element("cc").Element("icon").Value, description = item.Element("cc").Element("t").Value, links = from link in item.Elements("lnks").Elements("link") select new { url = link.Element("l").Value, text = link.Element("t").Value } }; // Load the root node to a variable, you may use foreach construct instead. var item1 = feedResult.First(); *If you want to learn more about LINQ and XML, read this nice blog from Scott GU. http://weblogs.asp.net/scottgu/archive/2007/08/07/using-linq-to-xml-and-how-to-build-a-custom-rss-feed-reader-with-it.aspx Now you have all the required values in item1. For e.g. if you want to get the temperature, use item1.temp; Now I just need to execute an SQL query against the database. See the connection part. using (SqlConnection conn = new SqlConnection(@"Data Source=sreeju\sqlexpress;Initial Catalog=Sample;Integrated Security=True")) { string strSql = @"update tblweather set lastupdated=getdate(), temparatureDateTime = @temparatureDateTime, temparature=@temparature, temparatureUnit=@temparatureUnit, iconId = @iconId, description=@description, link1url=@link1url, link1text=@link1text, link2url=@link2url, link2text=@link2text,link3url=@link3url, link3text=@link3text,link4url=@link4url, link4text=@link4text"; SqlCommand comm = new SqlCommand(strSql, conn); comm.Parameters.AddWithValue("temparatureDateTime", item1.tempDate); comm.Parameters.AddWithValue("temparature", item1.temp); comm.Parameters.AddWithValue("temparatureUnit", item1.unit); comm.Parameters.AddWithValue("description", item1.description); comm.Parameters.AddWithValue("iconId", item1.iconId); var lstLinks = item1.links; comm.Parameters.AddWithValue("link1url", lstLinks.ElementAt(0).url); comm.Parameters.AddWithValue("link1text", lstLinks.ElementAt(0).text); comm.Parameters.AddWithValue("link2url", lstLinks.ElementAt(1).url); comm.Parameters.AddWithValue("link2text", lstLinks.ElementAt(1).text); comm.Parameters.AddWithValue("link3url", lstLinks.ElementAt(2).url); comm.Parameters.AddWithValue("link3text", lstLinks.ElementAt(2).text); comm.Parameters.AddWithValue("link4url", lstLinks.ElementAt(3).url); comm.Parameters.AddWithValue("link4text", lstLinks.ElementAt(3).text); conn.Open(); comm.ExecuteNonQuery(); conn.Close(); Console.WriteLine("database updated"); } Now click ctrl + f5 to run the service. I got the following output Check your database and make sure, the data is updated with the latest information from the service. (Make sure you inserted one row in the database by entering some values before executing the service. Otherwise you need to modify your application code to count the rows and conditionally perform insert/update query) Display the Weather information in ASP.Net page Now you got all the data in the database. You just need to create a web application and display the data from the database. I created a new ASP.Net web application with a default.aspx page. In order to comply with the terms of weather.com, You need to use Weather.com logo along with the weather display. You can find the necessary logos to use under the folder “logos” in the SDK. Additionally copy any of the icon set from the folder “icons” to your web application. I used the 93x93 icon set. You are free to use any other sizes available. The design view of the page in VS2010 looks similar to the following. The page contains a heading, an image control (for displaying the weather icon), 2 label controls (for displaying temperature and weather description), 4 hyperlinks (for displaying the 4 promo links returned by the XOAP service) and weather.com logo with hyperlink to the weather.com home page. I am going to write code that will update the values of these controls from the values stored in the database by the service application as mentioned in the previous step. Go to the code behind file for the webpage, enter the following code under Page_Load event handler. using (SqlConnection conn = new SqlConnection(@"Data Source=sreeju\sqlexpress;Initial Catalog=Sample;Integrated Security=True")) { SqlCommand comm = new SqlCommand("select top 1 * from tblweather", conn); conn.Open(); SqlDataReader reader = comm.ExecuteReader(); if (reader.Read()) { lblTemparature.Text = reader["temparature"].ToString() + "&deg;" + reader["temparatureUnit"].ToString(); lblWeatherDescription.Text = reader["description"].ToString(); imgWeather.ImageUrl = "icons/" + reader["iconId"].ToString() + ".png"; lnk1.Text = reader["link1text"].ToString(); lnk1.NavigateUrl = reader["link1url"].ToString(); lnk2.Text = reader["link2text"].ToString(); lnk2.NavigateUrl = reader["link2url"].ToString(); lnk3.Text = reader["link3text"].ToString(); lnk3.NavigateUrl = reader["link3url"].ToString(); lnk4.Text = reader["link4text"].ToString(); lnk4.NavigateUrl = reader["link4url"].ToString(); } conn.Close(); } Press ctrl + f5 to run the page. You will see the following output. That’s it. You need to configure the console application to run every 25 minutes so that the database is updated. Also you can fetch the forecast information and store those in the database, and then retrieve it later in your web page. Since the data resides in your database, you have the full control over your display. You need to make sure your website comply with weather.com license requirements. If you want to get the source code of this walkthrough through the application, post your email address below. Hope you enjoy the reading.

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  • How to add icons to a PopUpMenuButton in Flex 3 using an XML file

    - by user168610
    Hi, I've been looking at the following example for populating a PupUpMenuButton http://blog.flexexamples.com/2008/02/21/creating-a-custom-label-function-on-a-flex-popupmenubutton-control/ and would like to add icons to each menu. Ideally, I would specify the icon in the xml and assign it in a similar way to using labelFunction for the text. I'm pretty new to Flex and would appreciate some guidance with this. The only information I've found via google is to create a menu as follows (seems I can't include more than one url, but it is an example that creates a menu object using the following function): private function initMenu():void { menu = new Menu(); menu.dataProvider = xmlList; menu.labelField = "@label"; menu.iconField = "@icon"; } but I would really prefer to build it all from the XML file. Many thanks, Bryn

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  • Laissez les bon temps rouler! (Microsoft BI Conference 2010)

    - by smisner
    "Laissez les bons temps rouler" is a Cajun phrase that I heard frequently when I lived in New Orleans in the mid-1990s. It means "Let the good times roll!" and encapsulates a feeling of happy expectation. As I met with many of my peers and new acquaintances at the Microsoft BI Conference last week, this phrase kept running through my mind as people spoke about their plans in their respective businesses, the benefits and opportunities that the recent releases in the BI stack are providing, and their expectations about the future of the BI stack. Notwithstanding some jabs here and there to point out the platform is neither perfect now nor will be anytime soon (along with admissions that the competitors are also not perfect), and notwithstanding several missteps by the event organizers (which I don't care to enumerate), the overarching mood at the conference was positive. It was a refreshing change from the doom and gloom hovering over several conferences that I attended in 2009. Although many people expect economic hardships to continue over the coming year or so, everyone I know in the BI field is busier than ever and expects to stay busy for quite a while. Self-Service BI Self-service was definitely a theme of the BI conference. In the keynote, Ted Kummert opened with a look back to a fairy tale vision of self-service BI that he told in 2008. At that time, the fairy tale future was a time when "every end user was able to use BI technologies within their job in order to move forward more effectively" and transitioned to the present time in which SQL Server 2008 R2, Office 2010, and SharePoint 2010 are available to deliver managed self-service BI. This set of technologies is presumably poised to address the needs of the 80% of users that Kummert said do not use BI today. He proceeded to outline a series of activities that users ought to be able to do themselves--from simple changes to a report like formatting or an addtional data visualization to integration of an additional data source. The keynote then continued with a series of demonstrations of both current and future technology in support of self-service BI. Some highlights that interested me: PowerPivot, of course, is the flagship product for self-service BI in the Microsoft BI stack. In the TechEd keynote, which was open to the BI conference attendees, Amir Netz (twitter) impressed the audience by demonstrating interactivity with a workbook containing 100 million rows. He upped the ante at the BI keynote with his demonstration of a future-state PowerPivot workbook containing over 2 billion records. It's important to note that this volume of data is being processed by a server engine, and not in the PowerPivot client engine. (Yes, I think it's impressive, but none of my clients are typically wrangling with 2 billion records at a time. Maybe they're thinking too small. This ability to work quickly with large data sets has greater implications for BI solutions than for self-service BI, in my opinion.) Amir also demonstrated KPIs for the future PowerPivot, which appeared to be easier to implement than in any other Microsoft product that supports KPIs, apart from simple KPIs in SharePoint. (My initial reaction is that we have one more place to build KPIs. Great. It's confusing enough. I haven't seen how well those KPIs integrate with other BI tools, which will be important for adoption.) One more PowerPivot feature that Amir showed was a graphical display of the lineage for calculations. (This is hugely practical, especially if you build up calculations incrementally. You can more easily follow the logic from calculation to calculation. Furthermore, if you need to make a change to one calculation, you can assess the impact on other calculations.) Another product demonstration will be available within the next 30 days--Pivot for Reporting Services. If you haven't seen this technology yet, check it out at www.getpivot.com. (It definitely has a wow factor, but I'm skeptical about its practicality. However, I'm looking forward to trying it out with data that I understand.) Michael Tejedor (twitter) demonstrated a feature that I think is really interesting and not emphasized nearly enough--overshadowed by PowerPivot, no doubt. That feature is the Microsoft Business Intelligence Indexing Connector, which enables search of the content of Excel workbooks and Reporting Services reports. (This capability existed in MOSS 2007, but was more cumbersome to implement. The search results in SharePoint 2010 are not only cooler, but more useful by describing whether the content is found in a table or a chart, for example.) This may yet be the dawning of the age of self-service BI - a phrase I've heard repeated from time to time over the last decade - but I think BI professionals are likely to stay busy for a long while, and need not start looking for a new line of work. Kummert repeatedly referenced strategic BI solutions in contrast to self-service BI to emphasize that self-service BI is not a replacement for the services that BI professionals provide. After all, self-service BI does not appear magically on user desktops (or whatever device they want to use). A supporting infrastructure is necessary, and grows in complexity in proportion to the need to simplify BI for users. It's one thing to hear the party line touted by Microsoft employees at the BI keynote, but it's another to hear from the people who are responsible for implementing and supporting it within an organization. Rob Collie (blog | twitter), Kasper de Jonge (blog | twitter), Vidas Matelis (site | twitter), and I were invited to join Andrew Brust (blog | twitter) as he led a Birds of a Feather session at TechEd entitled "PowerPivot: Is It the BI Deal-Changer for Developers and IT Pros?" I would single out the prevailing concern in this session as the issue of control. On one side of this issue were those who were concerned that they would lose control once PowerPivot is implemented. On the other side were those who believed that data should be freely accessible to users in PowerPivot, and even acknowledgment that users would get the data they want even if it meant they would have to manually enter into a workbook to have it ready for analysis. For another viewpoint on how PowerPivot played out at the conference, see Rob Collie's observations. Collaborative BI I have been intrigued by the notion of collaborative BI for a very long time. Before I discovered BI, I was a Lotus Notes developer and later a manager of developers, working in a software company that enabled collaboration in the legal industry. Not only did I help create collaborative systems for our clients, I created a complete project management from the ground up to collaboratively manage our custom development work. In that case, collaboration involved my team, my client contacts, and me. I was also able to produce my own BI from that system as well, but didn't know that's what I was doing at the time. Only in recent years has SharePoint begun to catch up with the capabilities that I had with Lotus Notes more than a decade ago. Eventually, I had the opportunity at that job to formally investigate BI as another product offering for our software, and the rest - as they say - is history. I built my first data warehouse with Scott Cameron (who has also ventured into the authoring world by writing Analysis Services 2008 Step by Step and was at the BI Conference last week where I got to reminisce with him for a bit) and that began a career that I never imagined at the time. Fast forward to 2010, and I'm still lauding the virtues of collaborative BI, if only the tools will catch up to my vision! Thus, I was anxious to see what Donald Farmer (blog | twitter) and Rita Sallam of Gartner had to say on the subject in their session "Collaborative Decision Making." As I suspected, the tools aren't quite there yet, but the vendors are moving in the right direction. One thing I liked about this session was a non-Microsoft perspective of the state of the industry with regard to collaborative BI. In addition, this session included a better demonstration of SharePoint collaborative BI capabilities than appeared in the BI keynote. Check out the video in the link to the session to see the demonstration. One of the use cases that was demonstrated was linking from information to a person, because, as Donald put it, "People don't trust data, they trust people." The Microsoft BI Stack in General A question I hear all the time from students when I'm teaching is how to know what tools to use when there is overlap between products in the BI stack. I've never taken the time to codify my thoughts on the subject, but saw that my friend Dan Bulos provided good insight on this topic from a variety of perspectives in his session, "So Many BI Tools, So Little Time." I thought one of his best points was that ideally you should be able to design in your tool of choice, and then deploy to your tool of choice. Unfortunately, the ideal is yet to become real across the platform. The closest we come is with the RDL in Reporting Services which can be produced from two different tools (Report Builder or Business Intelligence Development Studio's Report Designer), manually, or by a third-party or custom application. I have touted the idea for years (and publicly said so about 5 years ago) that eventually more products would be RDL producers or consumers, but we aren't there yet. Maybe in another 5 years. Another interesting session that covered the BI stack against a backdrop of competitive products was delivered by Andrew Brust. Andrew did a marvelous job of consolidating a lot of information in a way that clearly communicated how various vendors' offerings compared to the Microsoft BI stack. He also made a particularly compelling argument about how the existence of an ecosystem around the Microsoft BI stack provided innovation and opportunities lacking for other vendors. Check out his presentation, "How Does the Microsoft BI Stack...Stack Up?" Expo Hall I had planned to spend more time in the Expo Hall to see who was doing new things with the BI stack, but didn't manage to get very far. Each time I set out on an exploratory mission, I got caught up in some fascinating conversations with one or more of my peers. I find interacting with people that I meet at conferences just as important as attending sessions to learn something new. There were a couple of items that really caught me eye, however, that I'll share here. Pragmatic Works. Whether you develop SSIS packages, build SSAS cubes, or author SSRS reports (or all of the above), you really must take a look at BI Documenter. Brian Knight (twitter) walked me through the key features, and I must say I was impressed. Once you've seen what this product can do, you won't want to document your BI projects any other way. You can download a free single-user database edition, or choose from more feature-rich standard or professional editions. Microsoft Press ebooks. I also stopped by the O'Reilly Media booth to meet some folks that one of my acquisitions editors at Microsoft Press recommended. In case you haven't heard, Microsoft Press has partnered with O'Reilly Media for distribution and publishing. Apart from my interest in learning more about O'Reilly Media as an author, an advertisement in their booth caught me eye which I think is a really great move. When you buy Microsoft Press ebooks through the O'Reilly web site, you can receive it in any (or all) of the following formats where possible: PDF, epub, .mobi for Kindle and .apk for Android. You also have lifetime DRM-free access to the ebooks. As someone who is an avid collector of books, I fnd myself running out of room for storage. In addition, I travel a lot, and it's hard to lug my reference library with me. Today's e-reader options make the move to digital books a more viable way to grow my library. Having a variety of formats means I am not limited to a single device, and lifetime access means I don't have to worry about keeping track of where I've stored my files. Because the e-books are DRM-free, I can copy and paste when I'm compiling notes, and I can print pages when necessary. That's a winning combination in my mind! Overall, I was pleased with the BI conference. There were many more sessions that I couldn't attend, either because the room was full when I got there or there were multiple sessions running concurrently that I wanted to see. Fortunately, many of the sessions are accessible for viewing online at http://www.msteched.com/2010/NorthAmerica along with the TechEd sessions. You can spot the BI sessions by the yellow skyline on the title slide of the presentation as shown below. Share this post: email it! | bookmark it! | digg it! | reddit! | kick it! | live it!

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  • Ada and 'The Book'

    - by Phil Factor
    The long friendship between Charles Babbage and Ada Lovelace created one of the most exciting and mysterious of collaborations ever to have resulted in a technological breakthrough. The fireworks that created by the collision of two prodigious mathematical and creative talents resulted in an invention, the Analytical Engine, which went on to change society fundamentally. However, beyond that, we just don't know what the bulk of their collaborative work was about:;  it was done in strictest secrecy. Even the known outcome of their friendship, the first programmable computer, was shrouded in mystery. At the time, nobody, except close friends and family, had any idea of Ada Byron's contribution to the invention of the ‘Engine’, and how to program it. Her great insight was published in August 1843, under the initials AAL, standing for Ada Augusta Lovelace, her title then being the Countess of Lovelace. It was contained in a lengthy ‘note’ to her translation of a publication that remains the best description of Babbage's amazing Analytical Engine. The secret identity of the person behind those enigmatic initials was finally revealed by Prince de Polignac who, seventy years later, wrote to Ada's daughter to seek confirmation that her mother had, indeed, been the author of the brilliant sentences that described so accurately how Babbage's mechanical computer could be programmed with punch-cards. L.F. Menabrea's paper on the Analytical Engine first appeared in the 'Bibliotheque Universelle de Geneve' in October 1842, and Ada translated it anonymously for Taylor's 'Scientific Memoirs'. Charles Babbage was surprised that she had not written an original paper as she already knew a surprising amount about the way the machine worked. He persuaded her to at least write some explanatory notes. These notes ended up extending to four times the length of the original article and represented the first published account of how a machine could be programmed to perform any calculation. Her example of programming the Bernoulli sequence would have worked on the Analytical engine had the device’s construction been completed, and gave Ada an unassailable claim to have invented the art of programming. What was the reason for Ada's secrecy? She was the only legitimate child of Lord Byron, who was probably the best known celebrity of the age, so she was already famous. She was a senior aristocrat, with titles, a fortune in money and vast estates in the Midlands. She had political influence, and was the cousin of Lord Melbourne, who was the Prime Minister at that time. She was friendly with the young Queen Victoria. Her mathematical activities were a pastime, and not one that would be considered by others to be in keeping with her roles and responsibilities. You wouldn't dare to dream up a fictional heroine like Ada. She was dazzlingly beautiful and talented. She could speak several languages fluently, and play some musical instruments with professional skill. Contemporary accounts refer to her being 'accomplished in science, art and literature'. On top of that, she was a brilliant mathematician, a talent inherited from her mother, Annabella Milbanke. In her mother's circle of literary and scientific friends was Charles Babbage, and Ada's friendship with him dates from her teenage zest for Mathematics. She was one of the first people he'd ever met who understood what he had attempted to achieve with the 'Difference Engine', and with whom he could converse as intellectual equals. He arranged for her to have an education from the most talented academics in the country. Ada melted the heart of the cantankerous genius to the point that he became a faithful and loyal father-figure to her. She was one of the very few who could grasp the principles of the later, and very different, ‘Analytical Engine’ which was designed from the start to tackle a variety of tasks. Sadly, Ada Byron's life ended less than a decade after completing the work that assured her long-term fame, in November 1852. She was dying of cancer, her gambling habits had caused her to run up huge debts, she'd had more than one affairs, and she was being blackmailed. Her brilliant but unempathic mother was nursing her in her final illness, destroying her personal letters and records, and repaying her debts. Her husband was distraught but helpless. Charles Babbage, however, maintained his steadfast paternalistic friendship to the end. She appointed her loyal friend to be her executor. For years, she and Babbage had been working together on a secret project, known only as 'The Book'. We have a clue to what it was in a letter written by her nine years earlier, on 11th August 1843. It was a joint project by herself and Lord Lovelace, her husband, and was intended to involve Babbage's 'undivided energies'. It involved 'consulting your Engine' (it required Babbage’s computer). The letter gives no hint about the project except for the high-minded nature of its purpose, and its highly mathematical nature.  From then on, the surviving correspondence between the two gives only veiled references to 'The Book'. There isn't much, since Babbage later destroyed any letters that could have damaged her reputation within the Establishment. 'I cannot spare the book today, which I am very sorry for. At the moment I want it for constant reference, but I think you can have it tomorrow' (Oct 1844)  And 'I will send you the book directly, and you can say, when you receive it, how long you will want to keep it'. (Nov 1844)  The two of them were obviously intent on the work: She writes, four years later, 'I have an engagement for Wednesday which will prevent me from attending to your wishes about the book' (Dec 1848). This was something that they both needed to work on, but could not do in parallel: 'I will send the book on Tuesday, and it can be left with you till Friday' (11 Feb 1849). After six years work, it had been so well-handled that it was beginning to fall apart: 'Don't forget the new cover you promised for the book. The poor book is very shabby and wants one' (20 Sept 1849). So what was going on? The word 'book' was not a code-word: it was a real book, probably a 'printer's blank', plain paper, but properly bound so printers and publishers could show off how the published work might look. The hints from the correspondence are of advanced mathematics. It is obvious that the book was travelling between them, back and forth, each one working on it for less than a week before passing it back. Ada and her husband were certainly involved in gambling large sums of money on the horses, and so most biographers have concluded that the three of them were trying to calculate the mathematical odds on the horses. This theory has three large problems. Firstly, Ada's original letter proposing the project refers to its high-minded nature. Babbage was temperamentally opposed to gambling and would scarcely have given so much time to the project, even though he was devoted to Ada. Secondly, Babbage would have very soon have realized the hopelessness of trying to beat the bookies. This sort of betting never attracts his type of intellectual background. The third problem is that any work on calculating the odds on horses would not need a well-thumbed book to pass back and forth between them; they would have not had to work in series. The original project was instigated by Ada, along with her husband, William King-Noel, 1st Earl of Lovelace. Charles Babbage was invited to join the project after the couple had come up with the idea. What could William have contributed? One might assume that William was a Bertie Wooster character, addicted only to the joys of the turf, but this was far from the truth. He was a scientist, a Cambridge graduate who was later elected to be a Fellow of the Royal Society. After Eton, he went to Trinity College, Cambridge. On graduation, he entered the diplomatic service and acted as secretary under Lord Nugent, who was Lord Commissioner of the Ionian Islands. William was very friendly with Babbage too, able to discuss scientific matters on equal terms. He was a capable engineer who invented a process for bending large timbers by the application of steam heat. He delivered a paper to the Institution of Civil Engineers in 1849, and received praise from the great engineer, Isambard Kingdom Brunel. As well as being Lord Lieutenant of the County of Surrey for most of Victoria's reign, he had time for a string of scientific and engineering achievements. Whatever the project was, it is unlikely that William was a junior partner. After Ada's death, the project disappeared. Then, two years later, Babbage, through one of his occasional outbursts of temper, demonstrated that he was able to decrypt one of the most powerful of secret codes, Vigenère's autokey cipher.  All contemporary diplomatic and military messages used a variant of this cipher. Babbage had made three important discoveries, namely, the mathematical law of this cipher, the principle of the key periodicity, and the technique of the symmetry of position. The technique is now known as the Kasiski examination, also called the Kasiski test, but Babbage got there first. At one time, he listed amongst his future projects, the writing of a book 'The Philosophy of Decyphering', but it never came to anything. This discovery was going to change the course of history, since it was used to decipher the Russians’ military dispatches in the Crimean war. Babbage himself played a role during the Crimean War as a cryptographical adviser to his friend, Rear-Admiral Sir Francis Beaufort of the Admiralty. This is as much as we can be certain about in trying to make sense of the bulk of the time that Charles Babbage and Ada Lovelace worked together. Nine years of intensive work, involving the 'Engine' and a great deal of mathematics and research seems to have been lost: or has it? I've argued in the past http://www.simple-talk.com/community/blogs/philfactor/archive/2008/06/13/59614.aspx that the cracking of the Vigenère autokey cipher, was a fundamental motive behind the British Government's support and funding of the 'Difference Engine'. The Duke of Wellington, whose understanding of the military significance of being able to read enemy dispatches, was the most steadfast advocate of the project. If the three friends were actually doing the work of cracking codes by mathematical techniques that used the techniques of key periodicity, and symmetry of position (the use of a book being passed quickly to and fro is very suggestive), intending to then use the 'Engine' to do the routine cracking of each dispatch, then this is a rather different story. The project was Ada and William's idea. (William had served in the diplomatic service and would be familiar with the use of codes). This makes Ada Lovelace the initiator of a project which, by giving both Britain, and probably the USA, a diplomatic and military advantage in the second part of the Nineteenth century, changed world history. Ada would never have wanted any credit for cracking the cipher, and developing the method that rendered all contemporary military and diplomatic ciphering techniques nugatory; quite the reverse. And it is clear from the gaps in the record of the letters between the collaborators that the evidence was destroyed, probably on her request by her irascible but intensely honorable executor, Charles Babbage. Charles Babbage toyed with the idea of going public, but the Crimean war put an end to that. The British Government had a valuable secret, and intended to keep it that way. Ada and Charles had quite often discussed possible moneymaking projects that would fund the development of the Analytic Engine, the first programmable computer, but their secret work was never in the running as a potential cash cow. I suspect that the British Government was, even then, working on the concealment of a discovery whose value to the nation depended on it remaining so. The success of code-breaking in the Crimean war, and the American Civil war, led to the British and Americans  subsequently giving much more weight and funding to the science of decryption. Paradoxically, this makes Ada's contribution even closer to the creation of Colossus, the first digital computer, at Bletchley Park, specifically to crack the Nazi’s secret codes.

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