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  • What&rsquo;s in a name?

    - by Aaron Kowall
    My online presence has become caffeinatedgeek.  As such, I recently had my blog moved from geekswithblogs.net/aaronsblog to geekswithblogs.net/caffeinatedgeek. Same sporadic but hoepfully valuable posting, just new web home. Technorati Tags: caffeinatedgeek

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  • ASP.NET Chart Control - During a PostBack

    - by Guilherme Cardoso
    To use the Chart control from a PostBack is necessary to modify the ChartImg.axd HttpHandler, otherwise we'll get the error message: Error executing child request for ChartImg.axd In Web.Config search the line: <add path = "ChartImg.axd" verb = "GET,HEAD" type = "System.Web.UI.DataVisualization.Charting.ChartHttpHandler, System.Web.DataVisualization, Version=3.5.0.0, Culture=neutral, PublicKeyToken=31bf3856ad364e35" <Add path = "ChartImg.axd" verb = "GET, HEAD" type = "System.Web.UI.DataVisualization.Charting.ChartHttpHandler, System.Web.DataVisualization, Version = 3.5.0.0, Culture = neutral, PublicKeyToken = 31bf3856ad364e35 " validate = "false" /> Validate = "false" />   Change to: <add path = "ChartImg.axd" verb = "GET,HEAD,POST" type = "System.Web.UI.DataVisualization.Charting.ChartHttpHandler, System.Web.DataVisualization, Version=3.5.0.0, Culture=neutral, PublicKeyToken=31bf3856ad364e35" <Add path = "ChartImg.axd" verb = "GET, HEAD, POST" type = "System.Web.UI.DataVisualization.Charting.ChartHttpHandler, System.Web.DataVisualization, Version = 3.5.0.0, Culture = Neutral, PublicKeyToken = 31bf3856ad364e35 " validate = "false" /> validate = "false" /> The attribute that we are adding is the Post.  For those not familiar with this control is very useful for creating graphics. You can see more information here .

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  • Building the Ultimate SharePoint 2010 Development Environment

    - by Manesh Karunakaran
    It’s been more than a month since SharePoint 2010 RTMed. And a lot of people have downloaded and set up their very own SharePoint 2010 development rigs. And quite a few people have written blogs about setting up good development environments, there is even an MSDN article on it. Two of the blogs worth noting are from MVPs Sahil Malik and Wictor Wilén. Make sure that you check these out as well. Part of the bad side-effects of being a geek is the need to do the technical stuff the best way possible (pragmatic or otherwise), but the problem with this is that what is considered “best” is relative. Precisely the reason why you are reading this post now. Most of the posts that I read are out dated/need updations or are using the wrong OS’es or virtualization solutions (again, opinions vary) or using them the wrong way. Here’s a developer’s view of Building the Ultimate SharePoint 2010 Development Rig. If you are a sales guy, it’s time to close this window. Confusion 1: Which Host Operating System and Virtualization Solution to use? This point has been beaten to death in numerous blog posts in the past, if you have time to invest, read this excellent post by our very own SharePoint Joel on this subject. But if you are planning to build the Ultimate Development Rig, then Windows Server 2008 R2 with Hyper-V is the option that you should be looking at. I have been using this as my primary OS for about 6-7 months now, and I haven’t had any Driver issue or Application compatibility issue. In my experience all the Windows 7 drivers work fine with WIN2008 R2 also. You can enable Aero for eye candy (and the Windows 7 look and feel) and except for a few things like the Hibernation support (which a can be enabled if you really want it), Windows Server 2008 R2, is the best Workstation OS that I have used till date. But frankly the answer to this question of which OS to use depends primarily on one question - Are you willing to change your primary OS? If the answer to that is ‘Yes’, then Windows 2008 R2 with Hyper-V is the best option, if not look at vmWare or VirtualBox, both are equally good. Those who are familiar with a Virtual PC background might prefer Sun VirtualBox. Besides, these provide support for running 64 bit guest machines on 32 bit hosts if the underlying hardware is truly 64 bit. See my earlier post on this. Since we are going to make the ultimate rig, we will use Windows Server 2008 R2 with Hyper-V, for reasons mentioned above. Confusion 2: Should I use a multi-(virtual) server set up? A lot of people use multiple servers for their development environments - like Wictor Wilén is suggesting - one server hosting the Active directory, one hosting SharePoint Server and another one for SQL Server. True, this mimics the production environment the best possible way, but as somebody who has fallen for this set up earlier, I can tell you that you don’t really get anything by doing this. Microsoft has done well to ensure that if you can do it on one machine, you can do it in a farm environment as well. Besides, when you run multiple Server class machine instances in parallel, there are a lot of unwanted processor cycles wasted for no good use. In my personal experience, as somebody who needs to switch between MOSS 2007/SharePoint 2010 environments from time to time, the best possible solution is to Make the host Windows Server 2008 R2 machine your Domain Controller (AD Server) Make all your Virtual Guest OS’es join this domain. Have each Individual Guest OS Image have it’s own local SQL Server instance. The advantages are that you can reuse the users and groups in each of the Guest operating systems, you can manage the users in one place, AD is light weight and doesn't take too much resources on your host machine and also having separate SQL instances for each of the Development images gives you maximum flexibility in terms of configuration, for example your SharePoint rigs can have simpler DB configurations, compared to your MS BI blast pits. Confusion 3: Which Operating System should I use to run SharePoint 2010 Now that’s a no brainer. Use Windows 2008 R2 as your Guest OS. When you are building the ultimate rig, why compromise? If you are planning to run Windows Server 2008 as your Guest OS, there are a few patches that you need to install at different times during the installation, for that follow the steps mentioned here Okay now that we have made our choices, let’s get to the interesting part of building the rig, Step 1: Prepare the host machine – Install Windows Server 2008 R2 Install Windows Server 2008 R2 on your best Desktop/Laptop. If you have read this far, I am quite sure that you are somebody who can install an OS on your own, so go ahead and do that. Make sure that you run the compatibility wizard before you go ahead and nuke your current OS. There are plenty of blogs telling you how to make a good Windows 2008 R2 Workstation that feels and behaves like a Windows 7 machine, follow one and once you are done, head to Step 2. Step 2: Configure the host machine as a Domain Controller Before we begin this, let me tell you, this step is completely optional, you don’t really need to do this, you can simply use the local users on the Guest machines instead, but if this is a much cleaner approach to manage users and groups if you run multiple guest operating systems.  This post neatly explains how to configure your Windows Server 2008 R2 host machine as a Domain Controller. Follow those simple steps and you are good to go. If you are not able to get it to work, try this. Step 3: Prepare the guest machine – Install Windows Server 2008 R2 Open Hyper-V Manager Choose to Create a new Guest Operating system Allocate at least 2 GB of Memory to the Guest OS Choose the Windows 2008 R2 Installation Media Start the Virtual Machine to commence installation. Once the Installation is done, Activate the OS. Step 4: Make the Guest operating systems Join the Domain This step is quite simple, just follow these steps below, Fire up Hyper-V Manager, open your Guest OS Click on Start, and Right click on ‘Computer’ and choose ‘Properties’ On the window that pops-up, click on ‘Change Settings’ On the ‘System Properties’ Window that comes up, Click on the ‘Change’ button Now a window named ‘Computer Name/Domain Changes’ opens up, In the text box titled Domain, type in the Domain name from Step 2. Click Ok and windows will show you the welcome to domain message and ask you to restart the machine, click OK to restart. If the addition to domain fails, that means that you have not set up networking in Hyper-V for the Guest OS to communicate with the Host. To enable it, follow the steps I had mentioned in this post earlier. Step 5: Install SQL Server 2008 R2 on the Guest Machine SQL Server 2008 R2 gets installed with out hassle on Windows Server 2008 R2. SQL Server 2008 needs SP2 to work properly on WIN2008 R2. Also SQL Server 2008 R2 allows you to directly add PowerPivot support to SharePoint. Choose to install in SharePoint Integrated Mode in Reporting Server Configuration. Step 6: Install KB971831 and SharePoint 2010 Pre-requisites Now install the WCF Hotfix for Microsoft Windows (KB971831) from this location, and SharePoint 2010 Pre-requisites from the SP2010 Installation media. Step 7: Install and Configure SharePoint 2010 Install SharePoint 2010 from the installation media, after the installation is complete, you are prompted to start the SharePoint Products and Technologies Configuration Wizard. If you are using a local instance of Microsoft SQL Server 2008, install the Microsoft SQL Server 2008 KB 970315 x64 before starting the wizard. If your development environment uses a remote instance of Microsoft SQL Server 2008 or if it has a pre-existing installation of Microsoft SQL Server 2008 on which KB 970315 x64 has already been applied, this step is not necessary. With the wizard open, do the following: Install SQL Server 2008 KB 970315 x64. After the Microsoft SQL Server 2008 KB 970315 x64 installation is finished, complete the wizard. Alternatively, you can choose not to run the wizard by clearing the SharePoint Products and Technologies Configuration Wizard check box and closing the completed installation dialog box. Install SQL Server 2008 KB 970315 x64, and then manually start the SharePoint Products and Technologies Configuration Wizard by opening a Command Prompt window and executing the following command: C:\Program Files\Common Files\Microsoft Shared Debug\Web Server Extensions\14\BIN\psconfigui.exe The SharePoint Products and Technologies Configuration Wizard may fail if you are using a computer that is joined to a domain but that is not connected to a domain controller. Step 8: Install Visual Studio 2010 and SharePoint 2010 SDK Install Visual Studio 2010 Download and Install the Microsoft SharePoint 2010 SDK Step 9: Install PowerPivot for SharePoint and Configure Reporting Services Pop-In the SQLServer 2008 R2 installation media once again and install PowerPivot for SharePoint. This will get added as another instance named POWERPIVOT. Configure Reporting Services by following the steps mentioned here, if you need to get down to the details on how the integration between SharePoint 2010 and SQL Server 2008 R2 works, see Working Together: SQL Server 2008 R2 Reporting Services Integration in SharePoint 2010 an excellent article by Alan Le Marquand Step 10: Download and Install Sample Databases for Microsoft SQL Server 2008R2 SharePoint 2010 comes with a lot of cool stuff like PerformancePoint Services and BCS, if you need to try these out, you need to have data in your databases. So if you want to save yourself the trouble of creating sample data for your PerformancePoint and BCS experiments, download and install Sample Databases for Microsoft SQL Server 2008R2 from CodePlex. And you are done! Fire up your Visual Studio 2010 and Start Coding away!!

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  • List of Upcoming Appearances

    - by Chris Gardner
    Greetings. I know I have been in work sponsored hiding lately. We are working furiously on a beta project to secure a contract, and I can't really talk about it yet. Hopefully, the contracts will be soon signed. Not only will we then have money, but I can talk about all this really cool tech with which I have been playing. However, since the contract is not signed, I need to bring you people up to date with where I will be during the summer. Let's face it, you can't be a speaker / blogger without pandering to shameless self-promotion. First, I will, once again, be staffing the Hands-on-Labs at TechEd North America. Unfortunately, TechEd North America is already sold out for this year. However, if you're already going, drop by the labs and say Hi. Also, keep an eye on Twitter to track me throughout the event. Also, look for a post in a few hours with my specific picks for what content I'm looking forward to seeing this year. Immediately following TechEd North America, I will be flying into Knoxville to speak at CodeStock. I will be presenting my introduction and intermediate Xbox 360 development talks. There are a TON of great content at CodeStock this year, but there are only about 50 tickets left. After that whirlwind of work, things settle for awhile. That means I'm available to speak at your User Group, luncheon, bowling league, birthday party, anniversary, or bat mitzvah. Mid August brings us to That Conference. This one is going to be a blast. If you haven't heard of That Conference yet, you should really check it out. This will also be my introduction and intermediate Xbox 360 development talks. This is a new conference, and it looks like it will be a great one. Finally, we will turn our attention to DevLink. DevLink has the distinction of picking up my newest talk, Creating Stereoscopic 3D Graphics in XNA. On top of that, I'm giving an general Xbox 360 and Windows Phone 7 talk. DevLink has added an new "XNA and Kinect" track, so there will me a ton of great game content. That should bring us through the summer. As I solidify the Stereoscopic talk, look for some content on that to creep up on here. I will say it's the first topic I've played around with that is easier in 3D than 2D. Also, the organizers of Alabama Code Camp are still trying to reschedule the event. When that happens, I'll get that information out. Also, we are looking to expand our development team. If you are interested in working for / with me, keep an eye on the T & W Operations website. I know we're immediately looking for a junior level developer, but I think a few higher level position may come up soon. You MUST apply through the website, but drop me a personal line if you do apply. I'll keep an eye out for the application.

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  • West Palm Beach Dev Group August 2012 Meeting Recap

    - by Sam Abraham
    As the saying goes, it’s better late than never. Such is the case with my overdue West Palm Beach Dev Group August 2012 meeting report. Our August meeting was full of both knowledge and adventure. It comes as no surprise that the knowledge was brought to us by our favorite DotNetNuke Technical Evangelist, Will Strohl. Will introduced and thoroughly presented the new social features in DNN 6.2. Unfortunately, our meeting date coincided with Hurricane Isaac having just passed us by. Aside from road closures and floods that kept public schools closed for two days, our meeting host, PC Professor, had to close the school the day of our meeting on a short notice due to flooding which we found out about at midnight on the day of the event.  This left us scrambling to find an available alternate meeting location close enough to our original venue. Cancelling the meeting was always an option, but we opted to keep it as the very last resort. Luckily, we were fortunate to find a meeting room at the Hampton Inn only a few minutes away from our original location. Having heard of our challenge, our event sponsor, Applied Innovations, stepped-in and covered the meeting room cost in addition to the food and beverages. We would like to thank our volunteers and sponsors who made that event a success: Jess Coburn, CEO and Cara Pluff, Director of Sales at Applied Innovations, Dave Noderer for suggesting the alternate venue and Venkat Subramanian for his hard work keeping our members informed of the venue change and for being our event photographer.   We look forward to seeing you at our upcoming meetings: -September 25th, 2012 with Jonas Stawski, Microsoft MVP -October 23rd, 2012 with our Microsoft Developer Evangelist, Joe “DevFish” Healy -Ending an exciting year will be our November 27th meeting with Dycom Industries’ Senior Software Developer, Tom Huynh.   All the best, --Sam

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  • Converting Openfire IM datetime values in SQL Server to / from VARCHAR(15) and DATETIME data types

    - by Brian Biales
    A client is using Openfire IM for their users, and would like some custom queries to audit user conversations (which are stored by Openfire in tables in the SQL Server database). Because Openfire supports multiple database servers and multiple platforms, the designers chose to store all date/time stamps in the database as 15 character strings, which get converted to Java Date objects in their code (Openfire is written in Java).  I did some digging around, and, so I don't forget and in case someone else will find this useful, I will put the simple algorithms here for converting back and forth between SQL DATETIME and the Java string representation. The Java string representation is the number of milliseconds since 1/1/1970.  SQL Server's DATETIME is actually represented as a float, the value being the number of days since 1/1/1900, the portion after the decimal point representing the hours/minutes/seconds/milliseconds... as a fractional part of a day.  Try this and you will see this is true:     SELECT CAST(0 AS DATETIME) and you will see it returns the date 1/1/1900. The difference in days between SQL Server's 0 date of 1/1/1900 and the Java representation's 0 date of 1/1/1970 is found easily using the following SQL:   SELECT DATEDIFF(D, '1900-01-01', '1970-01-01') which returns 25567.  There are 25567 days between these dates. So to convert from the Java string to SQL Server's date time, we need to convert the number of milliseconds to a floating point representation of the number of days since 1/1/1970, then add the 25567 to change this to the number of days since 1/1/1900.  To convert to days, you need to divide the number by 1000 ms/s, then by  60 seconds/minute, then by 60 minutes/hour, then by 24 hours/day.  Or simply divide by 1000*60*60*24, or 86400000.   So, to summarize, we need to cast this string as a float, divide by 86400000 milliseconds/day, then add 25567 days, and cast the resulting value to a DateTime.  Here is an example:   DECLARE @tmp as VARCHAR(15)   SET @tmp = '1268231722123'   SELECT @tmp as JavaTime, CAST((CAST(@tmp AS FLOAT) / 86400000) + 25567 AS DATETIME) as SQLTime   To convert from SQL datetime back to the Java time format is not quite as simple, I found, because floats of that size do not convert nicely to strings, they end up in scientific notation using the CONVERT function or CAST function.  But I found a couple ways around that problem. You can convert a date to the number of  seconds since 1/1/1970 very easily using the DATEDIFF function, as this value fits in an Int.  If you don't need to worry about the milliseconds, simply cast this integer as a string, and then concatenate '000' at the end, essentially multiplying this number by 1000, and making it milliseconds since 1/1/1970.  If, however, you do care about the milliseconds, you will need to use DATEPART to get the milliseconds part of the date, cast this integer to a string, and then pad zeros on the left to make sure this is three digits, and concatenate these three digits to the number of seconds string above.  And finally, I discovered by casting to DECIMAL(15,0) then to VARCHAR(15), I avoid the scientific notation issue.  So here are all my examples, pick the one you like best... First, here is the simple approach if you don't care about the milliseconds:   DECLARE @tmp as VARCHAR(15)   DECLARE @dt as DATETIME   SET @dt = '2010-03-10 14:35:22.123'   SET @tmp = CAST(DATEDIFF(s, '1970-01-01 00:00:00' , @dt) AS VARCHAR(15)) + '000'   SELECT @tmp as JavaTime, @dt as SQLTime If you want to keep the milliseconds:   DECLARE @tmp as VARCHAR(15)   DECLARE @dt as DATETIME   DECLARE @ms as int   SET @dt = '2010-03-10 14:35:22.123'   SET @ms as DATEPART(ms, @dt)   SET @tmp = CAST(DATEDIFF(s, '1970-01-01 00:00:00' , @dt) AS VARCHAR(15))           + RIGHT('000' + CAST(@ms AS VARCHAR(3)), 3)   SELECT @tmp as JavaTime, @dt as SQLTime Or, in one fell swoop:   DECLARE @dt as DATETIME   SET @dt = '2010-03-10 14:35:22.123'   SELECT @dt as SQLTime     , CAST(DATEDIFF(s, '1970-01-01 00:00:00' , @dt) AS VARCHAR(15))           + RIGHT('000' + CAST( DATEPART(ms, @dt) AS VARCHAR(3)), 3) as JavaTime   And finally, a way to simply reverse the math used converting from Java date to SQL date. Note the parenthesis - watch out for operator precedence, you want to subtract, then multiply:   DECLARE @dt as DATETIME   SET @dt = '2010-03-10 14:35:22.123'   SELECT @dt as SQLTime     , CAST(CAST((CAST(@dt as Float) - 25567.0) * 86400000.0 as DECIMAL(15,0)) as VARCHAR(15)) as JavaTime Interestingly, I found that converting to SQL Date time can lose some accuracy, when I converted the time above to Java time then converted  that back to DateTime, the number of milliseconds is 120, not 123.  As I am not interested in the milliseconds, this is ok for me.  But you may want to look into using DateTime2 in SQL Server 2008 for more accuracy.

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  • Why is IaaS important in Azure&hellip;

    - by Steve Loethen
    Three weeks ago, Microsoft released the next phase of Azure.  I have had several clients waiting on this release.  The fact that they have been waiting and are now more receptive to looking at the cloud.  Customers expressed fear of the unknown.  And a fear of lack of control, even when that lack of control also means a huge degree of flexibility to innovate with concerns about the underlying infrastructure.  I think IaaS will be that “gateway drug” to get customers who have been hesitant to take another look at the cloud.  The dialog can change from the cloud being this big scary unknown to a resource for workloads.  The conversations should have always been, and can know be even stronger, geared toward the following points: 1) The cloud is not unicorns and glitter, the cloud is resources.  Compute, storage, db’s, services bus, cache…..  Like many of the resources we have on-premise.  Not magic, just another resource with advantages and obstacles like any other resource. 2) The cloud should be part of the conversation for any new project.  All of the same criteria should be applied, on-premise or off.  Cost, security, reliability, scalability, speed to deploy, cost of licenses, need to customize image, complex workloads.  We have been having these discussions for years when we talk about on-premise projects.  We make decisions on OS’s, Databases, ESB’s, configuration and products based on a myriad of factors.  We use the same factors but now we have a additional set of resources to consider in our process. 3) The cloud is a great solution looking for some interesting problems.  It is our job to recognize the right problems that fit into the cloud, weigh the factors and decide what to do. IaaS makes this discussion easier, offers more choices, and often choices that many enterprises will find more better than PaaS.  Looking forward to helping clients realize the power of the cloud.

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  • Microsoft gets a first for it&rsquo;s cloud security

    - by TATWORTH
    Originally posted on: http://geekswithblogs.net/TATWORTH/archive/2014/05/21/microsoft-gets-a-first-for-itrsquos-cloud-security.aspxAt http://blogs.technet.com/b/microsoft_blog/archive/2014/04/10/privacy-authorities-across-europe-approve-microsoft-s-cloud-commitments.aspx, the official Microsoft Blog by Brad Smith records that Microsoft now has approval by european data protection authorities that Microsoft’s Cloud Contracts meets EU data protection law.

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  • Sixeyed.Caching available now on NuGet and GitHub!

    - by Elton Stoneman
    Originally posted on: http://geekswithblogs.net/EltonStoneman/archive/2013/10/22/sixeyed.caching-available-now-on-nuget-and-github.aspxThe good guys at Pluralsight have okayed me to publish my caching framework (as seen in Caching in the .NET Stack: Inside-Out) as an open-source library, and it’s out now. You can get it here: Sixeyed.Caching source code on GitHub, and here: Sixeyed.Caching package v1.0.0 on NuGet. If you haven’t seen the course, there’s a preview here on YouTube: In-Process and Out-of-Process Caches, which gives a good flavour. The library is a wrapper around various cache providers, including the .NET MemoryCache, AppFabric cache, and  memcached*. All the wrappers inherit from a base class which gives you a set of common functionality against all the cache implementations: •    inherits OutputCacheProvider, so you can use your chosen cache provider as an ASP.NET output cache; •    serialization and encryption, so you can configure whether you want your cache items serialized (XML, JSON or binary) and encrypted; •    instrumentation, you can optionally use performance counters to monitor cache attempts and hits, at a low level. The framework wraps up different caches into an ICache interface, and it lets you use a provider directly like this: Cache.Memory.Get<RefData>(refDataKey); - or with configuration to use the default cache provider: Cache.Default.Get<RefData>(refDataKey); The library uses Unity’s interception framework to implement AOP caching, which you can use by flagging methods with the [Cache] attribute: [Cache] public RefData GetItem(string refDataKey) - and you can be more specific on the required cache behaviour: [Cache(CacheType=CacheType.Memory, Days=1] public RefData GetItem(string refDataKey) - or really specific: [Cache(CacheType=CacheType.Disk, SerializationFormat=SerializationFormat.Json, Hours=2, Minutes=59)] public RefData GetItem(string refDataKey) Provided you get instances of classes with cacheable methods from the container, the attributed method results will be cached, and repeated calls will be fetched from the cache. You can also set a bunch of cache defaults in application config, like whether to use encryption and instrumentation, and whether the cache system is enabled at all: <sixeyed.caching enabled="true"> <performanceCounters instrumentCacheTotalCounts="true" instrumentCacheTargetCounts="true" categoryNamePrefix ="Sixeyed.Caching.Tests"/> <encryption enabled="true" key="1234567890abcdef1234567890abcdef" iv="1234567890abcdef"/> <!-- key must be 32 characters, IV must be 16 characters--> </sixeyed.caching> For AOP and methods flagged with the cache attribute, you can override the compile-time cache settings at runtime with more config (keyed by the class and method name): <sixeyed.caching enabled="true"> <targets> <target keyPrefix="MethodLevelCachingStub.GetRandomIntCacheConfiguredInternal" enabled="false"/> <target keyPrefix="MethodLevelCachingStub.GetRandomIntCacheExpiresConfiguredInternal" seconds="1"/> </targets> It’s released under the MIT license, so you can use it freely in your own apps and modify as required. I’ll be adding more content to the GitHub wiki, which will be the main source of documentation, but for now there’s an FAQ to get you started. * - in the course the framework library also wraps NCache Express, but there's no public redistributable library that I can find, so it's not in Sixeyed.Caching.

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  • A SpecTECHular follow-up: Windows Server 2012 #HyperV, #SysCtr 2012 and #Windows8

    - by KeithMayer
    Last week, I had the pleasure of presenting at the New Horizons SpecTECHular events (www.spectechular.com) in Cincinnati and Dayton OH.  It was great meeting some very engaged IT Pros and discussing the new features of Windows Server 2012 Hyper-V, System Center 2012 / Private Cloud, and Windows 8.  Since there was so much interest in these topics, I've posted my decks online at the following link locations: What's New in Windows Server 2012 & Hyper-V What's New in Windows 8 for IT Professionals Building Private Clouds with System Center 2012 Once you've had a chance to review each deck, let me know if there's specific topics in which you have more interest.  If you have an IT Pro technical community located in the US Heartland, I'd also be happy to discuss presenting these topics at one of your upcoming events! - Keithhttp://keithmayer.com | Twitter: @KeithMayer | LinkedIn: http://linkedin.com/in/KeithM

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  • First look at the cloud with Google App Engine and Udacity

    - by Ken Hortsch
    Udacity is free online university and offers a CS253 intro to web development class.  Since I am currently a web developer/architect in ASP.Net (and recent project has brought me back to Java) it is a bit light.  However, it does offer me a nice problem set and my first exposure to writing cloud apps with GAE and Google Datastore. Steve Huffman, who developed reddit, is the instructor and does offer nice real-life stories.  Give it a look.

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  • Christian Radio Locator iPhone app

    - by Tim Hibbard
    For the last three months or so I've been working on an iPhone (and iPad) app in my spare time. It all started when I took the kids to Minneapolis and had a hard time finding radio stations to listen to on the trip. I looked in the App Store for an app that would use my GPS to show me Christian radio stations nearby, but there wasn't one. So I decided to build my own. Using public information from the FCC and a few other sources, I built a database in Google docs that contains the frequency for all Christian radio stations, where the tower is located and how far the tower can reach. I also included any streaming audio information and other contact information like Facebook or Twitter that I could find. Google spreadsheets publish in JSON format (yes, really) and Xcode can automatically deserialize JSON into a properly formatted entity. This is one area that Xcode is far superior to C#. In a just a few lines of code, I can have a list of in-memory strongly typed objects from a web-based JSON feed. To accomplish the same thing natively in .NET would be much more work and wouldn't feel nearly as clean when it was said and done. The snazzy icon shown above was built by my very talented wife. She hasn't yet provided any feedback on the app's user interface, which is why it is so plain and boring. I used a navigation view controller and EGO pull to refresh table view to construct the main window. Pulling down to refresh initiates a GPS lookup, which queries the database for radio stations in range (yes, you can pass parameters to Google spreadsheets and get a subset back in JSON). Pulling up on the table extends the range of the search and includes stations that may not be close enough to get clear audio. This feature is not that intuitive and the next version contains an update to that functionality. Tapping a cell will show a detail view that displays additional information about the station. The user can click to view the station on a map, click to listen to an online stream (if available) or click to see the station's Facebook or Twitter pages. Swiping back and forth on the table changes the information that is displayed on the right hand side of the table cell. It scrolls through the city where the tower is located, how far the phone is from the tower, the range of the tower and in the next version a signal strength indicator. This was pretty easy to implement once I figured out how to assign the gesture recognizer delegate.  Tapping and holding on a cell will jump the user to the map view screen. Which is pretty cool, but very hard for even a power user to discover. To tackle the issue of discoverability, the next version has a series of instructions displayed at the bottom of the screen to show the user the various shortcuts. Once the user has performed the swipes and long holds, the instructions disappear. I've learned a lot developing this app. Spending over a decade exclusively in .NET made the learning curve a bit steep, but once I learned the structure and syntax of Objective-C, I've learned to appreciate the power and simplicity of it. Here are a few screenshots. I would really appreciate any feedback and especially iTunes reviews. Technically it is open source and a smart googler could probably find it. I just haven't promoted it as open source.     Cross posted from timhibbard.com

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  • Win a set of Infragistics Silverlight Controls with Data Visualization!

    - by mbcrump
    Infragistics recently released their new Silverlight Data Visualization Controls. I saw a couple of samples and had to take a look. I headed over to their website and downloaded the controls. I first noticed the hospital floor-plan demo shown on their site and started thinking of ways that I could use this in my own organization. I emailed them asking if I could give away the Silverlight Data Visualization controls on my site and they said, Yes! They also wanted to throw in the standard Silverlight Line of Business controls. (combined they are worth about $3000 US). I am very thankful they were willing to help the Silverlight community with this giveaway. So some quick rules below: ----------------------------------------------------------------------------------------------------------------------------------------------------------- Win a FREE developer’s license of Infragistics Silverlight Controls with Data Visualization ($3000 Value) Random winner will be announced on January 1st, 2011! To be entered into the contest do the following things: Subscribe to my feed. Leave a comment below with a valid email account (I WILL NOT share this info with anyone.) For extra entries simply: Retweet a link to this page using the following URL [ http://mcrump.me/iscfree ]. It does not matter what the tweet says, just as long as the URL is the same. Unlimited tweets, but please don’t go crazy! This URL will allow me to track the users that Tweet this page. Don’t forget to visit Infragistics because they made this possible. ---------------------------------------------------------------------------------------------------------------------------------------------------------- Before we get started with the Silverlight Controls, here is a couple of links to bookmark: The Silverlight Line of Business Control page is here. You can also check out the live demos here. The Data Visualization page is here. You can also check out the live demos here. Don’t worry about the Samples/Help Documentation. You can install all of that to your local HDD when you are installing it. I am going to walk you through the Silverlight Controls recently released by Infragistics. Begin by downloading the trial version and running the executable. If you downloaded the Complete bundle then you will have the following options to pick from. I like having help documentation and samples on my local HDD in case I do not have access to the internet and want to code. After it is installed, you may want to take a look at your Toolbox in Visual Studio 2010. Look for NetAdvantage 10.3 Silverlight and you will see that you now have access to all of these controls. At this point, to use the controls it’s as simple as drag/drop onto your Silverlight container. It will create the proper Namespaces for you. I wanted to highlight a few of the controls that I liked the most: Grid – After using the Infragistics grid you will wonder how you ever survived using the grid supplied by Microsoft standard controls.  This grid was designed to get your application up and running very fast. It’s simple to bind, it handles LARGE DataSets, easy to filter and allows endless possibilities of formatting data. The screenshot below is an example of the grid. For a real-time updating demo click here. SpellChecker- If your users are creating emails or performing any other function that requires Spell Checking then this control is great. Check out the screenshots below: In this first screen, I have a word that is not in the dictionary [DotNet]. The Spell Checker finds the word and allows the user to correct it. What is so great about Infragistics controls is that it only takes a few lines of code to have a full-featured Spell Checker in your application. TagCloud – This is a control that I haven’t seen anywhere else. It allows you to create keywords for popular search terms. This is very similar to TagCloud seen all over the internet.  Below is a screenshot that shows “Facebook” being a very popular item in the cloud. You can link these items to a hyperlink if you wanted. Importing/Exporting from Excel – I work with data a majority of the time. We all know the importance of Excel in our organizations, its used a lot. With Infragistics controls it make importing and exporting data from a Grid into Excel a snap. One of the things that I liked most about this control was the option to choose the Excel format (2003 or 2007). I haven’t seen this feature in other controls. Creating/Saving/Extracting/Uploading Zip Files – This is another control that I haven’t seen many others making. It allows you to basically manipulate a zip file in any way you like. You can even create a password on the zip file. Schedule – The Schedule that Infragistics provides resembles Outlook’s calendar. I think that it’s important for a user to see your app for the first time and immediately be able to start using because they are already familiar with the UI. The Schedule control accomplishes that in my opinion. I have just barely scratched the surface with the Infragistics Silverlight Line of Business controls. To check all of them then click here. A quick thing to note is that this giveaway also comes with the following Silverlight Data Visualization Controls. Below is a screenshot that list all of them:   I wanted to highlight 2 of the controls that I liked the most: xamBarcode– The xamBarcode supports the following Symbologies: Below is an example of the barcode generated by Infragistics controls. This is a high resolution barcode that you will not have to wonder if your scanner can read it. As long as you have ink in your printer your barcode will read it. I used a Symbol barcode reader to test this barcode. xamTreemap– I’ve never seen a way of displaying data like this before, but I like it. You can style this anyway that you like of course and it also comes with an Office 2010 Theme. Thanks to Infragistics for providing the controls to one lucky reader. I hope that you enjoyed this post and good luck to those that entered the contest.  Subscribe to my feed

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  • Flashing your Windows Phone Dummies

    - by Martin Hinshelwood
    The rate at which vendors release new updates for the HD2 is ridiculously slow. You have to wait for Microsoft to release the new OS, then you wait for HTC to build it into a ROM, and then you have to wait up to 6 months for your operator to badly customise it for their network. Once Windows Phone 7 is released this problem should go away as Microsoft is likely to be able to update the phone over the air, but what do we do until then? I want Windows Mobile 6.5.5 now!   I’m an early adopter. If there is a new version of something then that’s the version I want. As long as you accept that you are using something on a “let the early adopter beware” and accept that there may be bugs, sometimes serious crippling bugs the go for it. Note that I won't be responsible if you end up bricking your phone, unlocking or flashing your radio or ROM can be risky. If you follow the instructions then you should be fine, I've flashed my phones (SPV, M300, M1000, M2000, M3100, TyTN, TyTN 2, HD2) hundreds of times without any problems! I have been using Windows Mobile 6.5.5 before it was called 6.5.5 and for long enough that I don’t even remember when I first started using it. I was using it on my HTC TyTN 2 before I got an HD2 a couple of months before Christmas, and the first custom ROM’s for the HD2 were a couple of months after that. I always update to the latest ROM that I like, and occasionally I go back to the stock ROM’s to have a look see, but I am always disappointed. Terms: Soft Reset: Same as pulling out the battery, but is like a reboot for your phone Hard Reset: Reinstalls the Operating system from the Image that is stored on it ROM: This is Image that is loaded onto your phone and it is used to reinstall your phone whenever you do a “hard reset”. Stock ROM: A ROM from the original vendor… So HTC Cook a ROM: Referring to Cooking a ROM is the process a ROM developer goes through to take all of the parts (OS, Drivers and Applications) that make up a running phone and compiling them into a ROM. ROM Kitchen: A place where you get an SDK and all the component parts of the phone: OD, Drivers and Application. There are usually lots of Tools for making it easier to compile and build the image. Flashing: The process of updating one of the layers of your phone with a new layer Bricked: This is what happens when flashing goes wrong. Your phone is now good for only one thing… stopping paper blowing away in a windy place. You can “cook” you own ROM using one of the many good “ROM Kitchens” or you can use a ROM built and tested by someone else. I have cooked my own ROM before, and while the tutorials are good, it is a lot of hassle. You can only Flash new ROM’s that are specifically for your phone only so find a ROM for your phone and XDA Developers is the best place to look. It has a forum based structure and you can find your phone quite easily. XDA Developer Forum Installing a new ROM does have its risks. In the past there have been stories about phones being “bricked” but I have not heard of a bricked phone for quite some years. if you follow the instructions carefully you should not have any problems. note: Most of the tools are written by people for whom English is not their first language to you will need concentrate hard to understand some of the instructions. Have you ever read a manual that was just literally translated from another language? Enough said… There are a number of layers on your phone that you will need to know about: SPL: This is the lowest level, like a BIOS on a PC and is the Operating Systems gateway to the hardware Radio: I think of this as the hardware drivers, and you will need a different Radio for CDMA than GSM networks ROM: This is like your Windows CD, but it is stored internally to the Phone. Flashing your phone consists of replacing one Image with another and then wiping your phone and automatically reinstall from the Image. Sometimes when you download an Image wither it is for a Radio or for ROM you only get a file called *.nbh. What do you do with this? Well you need an RUU application to push that Image to your phone. The RUU’s are different per phone, but there is a CustomRUU for the HD2 that will update your phone with any *.nbh placed in the same directory. Download and Instructions for CustomRUU #1 Flash HardSPL An SPL is kind of like a BIOS, and the default one has checks to make sure that you are only installing a signed ROM. This would prevent you from installing one that comes from any other source but the vendor. NOTE: Installing a HARD SPL invalidates your warranty so remember to Flash your phone with a “stock” vendor ROM before trying to send your phone in for repairs. Is the warranty reinstated when you go back to a stock ROM? I don’t know… Updating your SPL to a HardSPL effectively unlocks your phone so you can install anything you like. I would recommend the HardSPL2. Download and Instructions for HardSPL2 #2 Task29 One of the problems that has been seen on the HD2 when flashing new ROM’s is that things are left over from the old ROM. For a while the recommendation was to Flash a stock ROM first, but some clever cookies have come up with “Task29” which formats your phone first. After running this your phone will be blank and will only boot to the white HTC logo and no further. You should follow the instructions and reboot (remove battery) and hold down the “volume down” button while turning you HD2 on to enter the bootloader. From here you can run CustomRUU once the USB message appears. Download and Instructions for Task29 #2 Flash Radio You may need to play around with this one, there is no good and bad version and the latest is not always the best. You know that annoying thing when you hit “end call” on your phone and nothing happens? Well that's down to the Radio. Get this version right for you and you may even be able to make calls. From a Windows Mobile as well Download There are no instructions here, but they are the same as th ROM, but you use this *.nbh file. #3 Flash ROM If you have gotten this far then you are probably a pro by now Just download the latest ROM below and Flash to your phone. I have been really impressed by the Artemis line of ROM’s but it is no way the only choice. I like this one as the developer builds them as close to the stock ROM as possible while updating to the latest of everything. Download and Instructions for  Artemis HD2 vXX Conclusion While updating your ROM is not for the faint hearted it provides more options than the Stock ROM’s and quicker feature updates than waiting… Technorati Tags: WM6

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  • Modify Build Failure Work Item in TFS 2010 Build

    - by Jakob Ehn
    The default behaviour in TFS Team Build (all versions) is to create a bug work item when a build fails. This main benefit of this is that you get a work item for something that needs to be done, namely to fix the build!. When the developer responsible for the build failure has fixed the problem, he/she can associated that check-in with the work item that was created from the previous build failure. In TFS 2005/2008 you could modify the information in the created work item by changing some predefined properties in the TFSBuild.proj file:   <!-- WorkItemType The type of the work item created on a build failure. --> <WorkItemType>Bug</WorkItemType> <!-- WorkItemFieldValues Fields and values of the work item created on a build failure. Note: Use reference names for fields if you want the build to be resistant to field name changes. Reference names are language independent while friendly names are changed depending on the installed language. For example, "System.Reason" is the reference name for the "Reason" field. --> <WorkItemFieldValues>System.Reason=Build Failure;System.Description=Start the build using Team Build</WorkItemFieldValues> <!-- WorkItemTitle Title of the work item created on build failure. --> <WorkItemTitle>Build failure in build:</WorkItemTitle> <!-- DescriptionText History comment of the work item created on a build failure. --> <DescriptionText>This work item was created by Team Build on a build failure.</DescriptionText> <!-- BuildLogText Additional comment text for the work item created on a build failure. --> <BuildlogText>The build log file is at:</BuildlogText> <!-- ErrorWarningLogText Additional comment text for the work item created on a build failure. This text will only be added if there were errors or warnings. --> <ErrorWarningLogText>The errors/warnings log file is at:</ErrorWarningLogText>   In TFS 2010, with Windows Workflow, you change this by modifying the properties on the OpenWorkItem activity. The hardest part of this is to actually find where this activity is located in the build process workflow. If you open the build definition in XAML you can just search for OpenWorkItem. If you use the designer you need to click your way down to the Catch section of the Try to Compile the Project sequence: To change the default values of the created work item, select the Created Work Item activity and look at the Properties window: Note the CustomFields property which is a dictionary with key (work item field name) and value. If you add custom fields to your work item you can add a value for it here by adding a new entry in the dictionary.

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  • Persistent Storage in Windows Phone 7

    - by Richard Jones
    Mark Arteaga – fellow MVP just helped me with this,  thought I’d share. Windows Phone 7 SilverLight supports persistent storage, which is a great way of saving settings betweens runs of your application. However I couldn’t get it to work. If you do this to create a persistant storage instance -    private IsolatedStorageSettings userSettings = IsolatedStorageSettings.ApplicationSettings; To retrieve settings do the following - string xx = userSettings[“SomeValue”].ToString();   Hiowever the bit that got me was how to save settings, you have todo this - userSettings.Add("Hello", DateTime.Now.ToShortTimeString());           userSettings.Save(); // <- This is the bit that got me   Hope this helps others

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  • A few things I learned regarding Azure billing policies

    - by Vincent Grondin
    An hour of small computing time: 0,12$ per hour A Gig of storage in the cloud: 0,15$ per hour 1 Gig of relational database using Azure SQL: 9,99$  per month A Visual Studio Professional with MSDN Premium account: 2500$ per year Winning an MSDN Professional account that comes preloaded with 750 free hours of Azure per month:  PRICELESS !!!      But was it really free???? Hmmm… Let’s see.....   Here's a few things I learned regarding Azure billing policies when I attended a promotional training at Microsoft last week...   1)  An instance deployed in the cloud really means whatever you upload in there... it doesn't matter if it's in STAGING OR PRODUCTION!!!!   Your MSDN account comes with 750 free hours of small computing time per month which should be enough hours per month for one instance of one application deployed in the cloud...  So we're cool, the application you run in the cloud doesn't cost you a penny....  BUT the one that's in staging is still consuming time!!!   So if you don’t want to end up having to pay 42$ at the end of the month on your credit card like this happened to a friend of mine, DELETE them staging applications once you’ve put them in production! This also applies to the instance count you can modify in the configuration file… So stop and think before you decide you want to spawn 50 of those hello world apps  .     2) If you have an MSDN account, then you have the promotional 750 hours of Azure credits per month and can use the Azure credits to explore the Cloud! But be aware, this promotion ends in 8 months (maybe more like 7 now) and then you will most likely go back to the standard 250 hours of Azure credits. If you do not delete your applications by then, you’ll get billed for the extra hours, believe me…   There is a switch that you can toggle and which will STOP your automatic enrollment after the promotion and prevent you from renewing the Azure Account automatically. Yes the default setting is to automatically renew your account and remember, you entered your credit card information in the registration process so, yes, you WILL be billed…  Go disable that ASAP    Log into your account, go to “Windows Azure Platform” then click the “Subscriptions” tab and on the right side, you’ll see a drop down with different “Actions” into it… Choose “Opt out of auto renew” and, NOW you’re safe…   Still, this is a great offer by Microsoft and I think everyone that has a chance should play a bit with Azure to get to know this technology a bit more...     Happy Cloud Computing All

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  • Windows CE training in Italy

    - by Valter Minute
    Se volete approfondire le vostre conoscenze su Windows CE (anche relativamente alle novità introdotte con la versione R3), o desiderate acquisire le basi per cominciare a lavorare con questo sistema operativo, questa è un'occasione da non perdere. Dal 12 al 16 Aprile si terrà presso gli uffici di Fortech Embedded Labs di Saronno (VA) il corso "Building Solutions with Windows Embedded CE 6.0", tenuto dal sottoscritto. Per maggiori informazioni sui contenuti e i costi: http://www.fortechembeddedlabs.it/node/27

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  • SQL Sharding and SQL Azure&hellip;

    - by Dave Noderer
    Herve Roggero has just published a paper that outlines patterns for scaling using SQL Azure and the Blue Syntax (he and Scott Klein’s company) sharding api. You can find the paper at: http://www.bluesyntax.net/files/EnzoFramework.pdf Herve and Scott have also just released an Apress book Pro SQL Azure. The idea of being able to split (shard) database operations automatically and control them from a web based management console is very appealing. These ideas have been talked about for a long time and implemented in thousands of very custom ways that have been costly, complicated and fragile. Now, there is light at the end of the tunnel. Scaling database access will become easier and move into the mainstream of application development. The main cost is using an api whenever accessing the database. The api will direct the query to the correct database(s) which may be located locally or in the cloud. It is inevitable that the api will change in the future, perhaps incorporated into a Microsoft offering. Even if this is the case, your application has now been architected to utilize these patterns and details of the actual api will be less important. Herve does a great job of laying out the concepts which every developer and architect should be familiar with!

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  • 7 Habits of Highly Effective Media Queries - by Brad Frost

    - by ihaynes
    Originally posted on: http://geekswithblogs.net/ihaynes/archive/2013/10/11/7-habits-of-highly-effective-media-queries---by-brad.aspxBrad Frost, one of the original proponents of responsive design, has written a great article on the "7 Habits of Highly Effective Media Queries".Let content determine breakpointsTreat layout as an enhancementUse major and minor breakpointsUse relative unitsGo beyond widthUse media queries for conditional loadingDon't go overboardGot you wondering? Read Brad's full article.Oh, and if you haven't read Steven Covey's original "7 Habits of Highly Effective People" book, it's a valuable read too, and might just change the way you relate to others and the world around you.

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  • It&rsquo;s ok to throw System.Exception&hellip;

    - by Chris Skardon
    No. No it’s not. It’s not just me saying that, it’s the Microsoft guidelines: http://msdn.microsoft.com/en-us/library/ms229007.aspx  Do not throw System.Exception or System.SystemException. Also – as important: Do not catch System.Exception or System.SystemException in framework code, unless you intend to re-throw.. Throwing: Always, always try to pick the most specific exception type you can, if the parameter you have received in your method is null, throw an ArgumentNullException, value received greater than expected? ArgumentOutOfRangeException. For example: public void ArgChecker(int theInt, string theString) { if (theInt < 0) throw new ArgumentOutOfRangeException("theInt", theInt, "theInt needs to be greater than zero."); if (theString == null) throw new ArgumentNullException("theString"); if (theString.Length == 0) throw new ArgumentException("theString needs to have content.", "theString"); } Why do we want to do this? It’s a lot of extra code when compared with a simple: public void ArgChecker(int theInt, string theString) { if (theInt < 0 || string.IsNullOrWhiteSpace(theString)) throw new Exception("The parameters were invalid."); } It all comes down to a couple of things; the catching of the exceptions, and the information you are passing back to the calling code. Catching: Ok, so let’s go with introduction level Exception handling, taught by many-a-university: You do all your work in a try clause, and catch anything wrong in the catch clause. So this tends to give us code like this: try { /* All the shizzle */ } catch { /* Deal with errors */ } But of course, we can improve on that by catching the exception so we can report on it: try { } catch(Exception ex) { /* Log that 'ex' occurred? */ } Now we’re at the point where people tend to go: Brilliant, I’ve got exception handling nailed, what next??? and code gets littered with the catch(Exception ex) nastiness. Why is it nasty? Let’s imagine for a moment our code is throwing an ArgumentNullException which we’re catching in the catch block and logging. Ok, the log entry has been made, so we can debug the code right? We’ve got all the info… What about an OutOfMemoryException – what can we do with that? That’s right, not a lot, chances are you can’t even log it (you are out of memory after all), but you’ve caught it – and as such - have hidden it. So, as part of this, there are two things you can do one, is the rethrow method: try { /* code */ } catch (Exception ex) { //Log throw; } Note, it’s not catch (Exception ex) { throw ex; } as that will wipe all your important stack trace information. This does get your exception to continue, and is the only reason you would catch Exception (anywhere other than a global catch-all) in your code. The other preferred method is to catch the exceptions you can deal with. It may not matter that the string I’m passing in is null, and I can cope with it like this: try{ DoSomething(myString); } catch(ArgumentNullException){} And that’s fine, it means that any exceptions I can’t deal with (OutOfMemory for example) will be propagated out to other code that can deal with it. Of course, this is horribly messy, no one wants try / catch blocks everywhere and that’s why Microsoft added the ‘Try’ methods to the framework, and it’s a strategy we should continue. If I try: int i = (int) "one"; I will get an InvalidCastException which means I need the try / catch block, but I could mitigate this using the ‘TryParse’ method: int i; if(!Int32.TryParse("one", out i)) return; Similarly, in the ‘DoSomething’ example, it might be beneficial to have a ‘TryDoSomething’ that returns a boolean value indicating the success of continuing. Obviously this isn’t practical in every case, so use the ol’ common sense approach. Onwards Yer thanks Chris, I’m looking forward to writing tonnes of new code. Fear not, that is where helpers come into it… (but that’s the next post)

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  • Sorting Algorithms

    - by MarkPearl
    General Every time I go back to university I find myself wading through sorting algorithms and their implementation in C++. Up to now I haven’t really appreciated their true value. However as I discovered this last week with Dictionaries in C# – having a knowledge of some basic programming principles can greatly improve the performance of a system and make one think twice about how to tackle a problem. I’m going to cover briefly in this post the following: Selection Sort Insertion Sort Shellsort Quicksort Mergesort Heapsort (not complete) Selection Sort Array based selection sort is a simple approach to sorting an unsorted array. Simply put, it repeats two basic steps to achieve a sorted collection. It starts with a collection of data and repeatedly parses it, each time sorting out one element and reducing the size of the next iteration of parsed data by one. So the first iteration would go something like this… Go through the entire array of data and find the lowest value Place the value at the front of the array The second iteration would go something like this… Go through the array from position two (position one has already been sorted with the smallest value) and find the next lowest value in the array. Place the value at the second position in the array This process would be completed until the entire array had been sorted. A positive about selection sort is that it does not make many item movements. In fact, in a worst case scenario every items is only moved once. Selection sort is however a comparison intensive sort. If you had 10 items in a collection, just to parse the collection you would have 10+9+8+7+6+5+4+3+2=54 comparisons to sort regardless of how sorted the collection was to start with. If you think about it, if you applied selection sort to a collection already sorted, you would still perform relatively the same number of iterations as if it was not sorted at all. Many of the following algorithms try and reduce the number of comparisons if the list is already sorted – leaving one with a best case and worst case scenario for comparisons. Likewise different approaches have different levels of item movement. Depending on what is more expensive, one may give priority to one approach compared to another based on what is more expensive, a comparison or a item move. Insertion Sort Insertion sort tries to reduce the number of key comparisons it performs compared to selection sort by not “doing anything” if things are sorted. Assume you had an collection of numbers in the following order… 10 18 25 30 23 17 45 35 There are 8 elements in the list. If we were to start at the front of the list – 10 18 25 & 30 are already sorted. Element 5 (23) however is smaller than element 4 (30) and so needs to be repositioned. We do this by copying the value at element 5 to a temporary holder, and then begin shifting the elements before it up one. So… Element 5 would be copied to a temporary holder 10 18 25 30 23 17 45 35 – T 23 Element 4 would shift to Element 5 10 18 25 30 30 17 45 35 – T 23 Element 3 would shift to Element 4 10 18 25 25 30 17 45 35 – T 23 Element 2 (18) is smaller than the temporary holder so we put the temporary holder value into Element 3. 10 18 23 25 30 17 45 35 – T 23   We now have a sorted list up to element 6. And so we would repeat the same process by moving element 6 to a temporary value and then shifting everything up by one from element 2 to element 5. As you can see, one major setback for this technique is the shifting values up one – this is because up to now we have been considering the collection to be an array. If however the collection was a linked list, we would not need to shift values up, but merely remove the link from the unsorted value and “reinsert” it in a sorted position. Which would reduce the number of transactions performed on the collection. So.. Insertion sort seems to perform better than selection sort – however an implementation is slightly more complicated. This is typical with most sorting algorithms – generally, greater performance leads to greater complexity. Also, insertion sort performs better if a collection of data is already sorted. If for instance you were handed a sorted collection of size n, then only n number of comparisons would need to be performed to verify that it is sorted. It’s important to note that insertion sort (array based) performs a number item moves – every time an item is “out of place” several items before it get shifted up. Shellsort – Diminishing Increment Sort So up to now we have covered Selection Sort & Insertion Sort. Selection Sort makes many comparisons and insertion sort (with an array) has the potential of making many item movements. Shellsort is an approach that takes the normal insertion sort and tries to reduce the number of item movements. In Shellsort, elements in a collection are viewed as sub-collections of a particular size. Each sub-collection is sorted so that the elements that are far apart move closer to their final position. Suppose we had a collection of 15 elements… 10 20 15 45 36 48 7 60 18 50 2 19 43 30 55 First we may view the collection as 7 sub-collections and sort each sublist, lets say at intervals of 7 10 60 55 – 20 18 – 15 50 – 45 2 – 36 19 – 48 43 – 7 30 10 55 60 – 18 20 – 15 50 – 2 45 – 19 36 – 43 48 – 7 30 (Sorted) We then sort each sublist at a smaller inter – lets say 4 10 55 60 18 – 20 15 50 2 – 45 19 36 43 – 48 7 30 10 18 55 60 – 2 15 20 50 – 19 36 43 45 – 7 30 48 (Sorted) We then sort elements at a distance of 1 (i.e. we apply a normal insertion sort) 10 18 55 60 2 15 20 50 19 36 43 45 7 30 48 2 7 10 15 18 19 20 30 36 43 45 48 50 55 (Sorted) The important thing with shellsort is deciding on the increment sequence of each sub-collection. From what I can tell, there isn’t any definitive method and depending on the order of your elements, different increment sequences may perform better than others. There are however certain increment sequences that you may want to avoid. An even based increment sequence (e.g. 2 4 8 16 32 …) should typically be avoided because it does not allow for even elements to be compared with odd elements until the final sort phase – which in a way would negate many of the benefits of using sub-collections. The performance on the number of comparisons and item movements of Shellsort is hard to determine, however it is considered to be considerably better than the normal insertion sort. Quicksort Quicksort uses a divide and conquer approach to sort a collection of items. The collection is divided into two sub-collections – and the two sub-collections are sorted and combined into one list in such a way that the combined list is sorted. The algorithm is in general pseudo code below… Divide the collection into two sub-collections Quicksort the lower sub-collection Quicksort the upper sub-collection Combine the lower & upper sub-collection together As hinted at above, quicksort uses recursion in its implementation. The real trick with quicksort is to get the lower and upper sub-collections to be of equal size. The size of a sub-collection is determined by what value the pivot is. Once a pivot is determined, one would partition to sub-collections and then repeat the process on each sub collection until you reach the base case. With quicksort, the work is done when dividing the sub-collections into lower & upper collections. The actual combining of the lower & upper sub-collections at the end is relatively simple since every element in the lower sub-collection is smaller than the smallest element in the upper sub-collection. Mergesort With quicksort, the average-case complexity was O(nlog2n) however the worst case complexity was still O(N*N). Mergesort improves on quicksort by always having a complexity of O(nlog2n) regardless of the best or worst case. So how does it do this? Mergesort makes use of the divide and conquer approach to partition a collection into two sub-collections. It then sorts each sub-collection and combines the sorted sub-collections into one sorted collection. The general algorithm for mergesort is as follows… Divide the collection into two sub-collections Mergesort the first sub-collection Mergesort the second sub-collection Merge the first sub-collection and the second sub-collection As you can see.. it still pretty much looks like quicksort – so lets see where it differs… Firstly, mergesort differs from quicksort in how it partitions the sub-collections. Instead of having a pivot – merge sort partitions each sub-collection based on size so that the first and second sub-collection of relatively the same size. This dividing keeps getting repeated until the sub-collections are the size of a single element. If a sub-collection is one element in size – it is now sorted! So the trick is how do we put all these sub-collections together so that they maintain their sorted order. Sorted sub-collections are merged into a sorted collection by comparing the elements of the sub-collection and then adjusting the sorted collection. Lets have a look at a few examples… Assume 2 sub-collections with 1 element each 10 & 20 Compare the first element of the first sub-collection with the first element of the second sub-collection. Take the smallest of the two and place it as the first element in the sorted collection. In this scenario 10 is smaller than 20 so 10 is taken from sub-collection 1 leaving that sub-collection empty, which means by default the next smallest element is in sub-collection 2 (20). So the sorted collection would be 10 20 Lets assume 2 sub-collections with 2 elements each 10 20 & 15 19 So… again we would Compare 10 with 15 – 10 is the winner so we add it to our sorted collection (10) leaving us with 20 & 15 19 Compare 20 with 15 – 15 is the winner so we add it to our sorted collection (10 15) leaving us with 20 & 19 Compare 20 with 19 – 19 is the winner so we add it to our sorted collection (10 15 19) leaving us with 20 & _ 20 is by default the winner so our sorted collection is 10 15 19 20. Make sense? Heapsort (still needs to be completed) So by now I am tired of sorting algorithms and trying to remember why they were so important. I think every year I go through this stuff I wonder to myself why are we made to learn about selection sort and insertion sort if they are so bad – why didn’t we just skip to Mergesort & Quicksort. I guess the only explanation I have for this is that sometimes you learn things so that you can implement them in future – and other times you learn things so that you know it isn’t the best way of implementing things and that you don’t need to implement it in future. Anyhow… luckily this is going to be the last one of my sorts for today. The first step in heapsort is to convert a collection of data into a heap. After the data is converted into a heap, sorting begins… So what is the definition of a heap? If we have to convert a collection of data into a heap, how do we know when it is a heap and when it is not? The definition of a heap is as follows: A heap is a list in which each element contains a key, such that the key in the element at position k in the list is at least as large as the key in the element at position 2k +1 (if it exists) and 2k + 2 (if it exists). Does that make sense? At first glance I’m thinking what the heck??? But then after re-reading my notes I see that we are doing something different – up to now we have really looked at data as an array or sequential collection of data that we need to sort – a heap represents data in a slightly different way – although the data is stored in a sequential collection, for a sequential collection of data to be in a valid heap – it is “semi sorted”. Let me try and explain a bit further with an example… Example 1 of Potential Heap Data Assume we had a collection of numbers as follows 1[1] 2[2] 3[3] 4[4] 5[5] 6[6] For this to be a valid heap element with value of 1 at position [1] needs to be greater or equal to the element at position [3] (2k +1) and position [4] (2k +2). So in the above example, the collection of numbers is not in a valid heap. Example 2 of Potential Heap Data Lets look at another collection of numbers as follows 6[1] 5[2] 4[3] 3[4] 2[5] 1[6] Is this a valid heap? Well… element with the value 6 at position 1 must be greater or equal to the element at position [3] and position [4]. Is 6 > 4 and 6 > 3? Yes it is. Lets look at element 5 as position 2. It must be greater than the values at [4] & [5]. Is 5 > 3 and 5 > 2? Yes it is. If you continued to examine this second collection of data you would find that it is in a valid heap based on the definition of a heap.

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