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  • Outlook Web Access and Rules

    - by Chris_K
    One of my clients would prefer that I have an email address in their domain. They run SBS 2k8 so I just monitor my email from them (and their clients) via Outlook Web Access. No POP or IMAP access, only OWA. No VPN access either, so no "real" Outlook. Just OWA. I figured I'd build an outlook rule to forward mail from that account to an account that I monitor -- that way I won't need to keep IE open all the time to monitor email. However, I just can't seem to get the dang rule to work and am hoping someone here can give me a nudge or pointer. From OWA, I click on Options - Rules and edit my current rule that kinda works. The rule is supposed to forward the email sent to me and then move it to a folder. It does move it to a folder... just never seems to forward it. The rule looks like this: Apply this rule after the message arrives where my name is in the To box redirect it to [email protected] and move it to the Forwarded to MyEmail folder except with "ALERT" in the subject As I mentioned, mail does get moved, just never redirected. I've tried "Forward" and "redirect" actions with the same results. Any suggestions?

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  • Multiple Video Cards - Stuttering

    - by jstawski
    I have two video cards: - XFX PVT84JUDD3 GeForce 8600GT XXX 256MB 128-bit GDDR3 PCI Express x16 SLI Supported Video Card - EVGA 256-P1-N399-LX GeForce 6200 256MB 64-bit GDDR2 PCI Video Card both running the same set of drivers on Windows 7 64-bit. When I work with 2 monitors connected to the 8600GT card everything works smoothly. When I connect the third one to the 6200 then Windows works well and all of a suddon the screens turns black for up to 5 minutes. Then it goes back and at some random interval it goes black again. I can still see the pointer and hit CTRL+ALT+DEL and see the menu to log off, bring the task manager, etc. I've tried changing the 6200 to another PCI slot and the error persists. I've tried connecting 2 monitors only one to each card, same problem. Tried swapping them, mixed and matched the monitors to see if it was a problem with the monitor and my conclusion was that it is not the monitor. The problem also occurred with Vista 64 as well. What could be generating this problem? Can it be the fact that they are different interfaces? Maybe the Motherboard? Should I change something on the BIOS? What do you guys think?

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  • Looking for an application that scrolls or pans netbook screens running Windows

    - by therobyouknow
    I'm looking for a Windows 7 and XP compatible Windows desktop panning/scrolling tool. This is to solve a problem where some applications for example MSN have settings/preference Windows that are not resizeable. I have a Netbook with a small maximum screen resolution e.g. 1024x600. The fixed non-resizeable windows are too large for this display screen size so I cannot see all of the items on these windows, particularly the OK button to save settings. What I would like is a desktop scrolling/panning tool where if I move my mouse pointer to any edge of the display, it pans to show the region of the too-large-fixed window that I could not see. I use a Samsung N110 and Toshiba NB100 netbooks. I'm looking for: A general program that provides desktop panning/scrolling/expanded resolution to allow all regions of a non-resizeable fixed window Preferably a non-graphics hardware specific program but will accept a solution that works with both the above machines I'm NOT looking for (i.e. unsatisfactory answers others have asked that I've already searched and found): Advice on what programs to use that DON'T have the problem of fixed windows Alternative operating system solutions Plugging in an external monitor with larger resolution - I use this option but I need a solution when one is not available, e.g. while travelling etc Advice about not using small screen netbooks - I enjoy the compact convenience of them Advice about change the dpi settings in the Control Panel Display settings Advice about guesswork with the tab key to move the focus the off-screen item I cannot see Thank you in advance.

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  • My Reverse DNS PTR record seems to be right, but I'm still getting bouncing email

    - by johnbr
    Hello, I have a service (statusme.com) where I let people know (for example) that their kid's soccer games are cancelled because of bad weather. We send out emails to the people who have registered. I have a second server as a backup, (vps.statusme.com) and I've set up the application to send some of the email through the second server. But I'm getting complaints from various recipient SMTP servers that the email is considered spam. So I did some investigating, and it appears that they think my reverse DNS record isn't correct. But when I look at it via various rDNS websites and instructions I found elsewhere on ServerFault, everything looks correct: jb$ host -t a vps.statusme.com 8.8.8.8 Using domain server: Name: 8.8.8.8 Address: 8.8.8.8#53 Aliases: vps.statusme.com has address 66.84.8.246 jb$ host -t ptr 246.8.84.66.in-addr.arpa 8.8.8.8 Using domain server: Name: 8.8.8.8 Address: 8.8.8.8#53 Aliases: 246.8.84.66.in-addr.arpa domain name pointer vps.statusme.com. I'm confused about what I'm doing wrong. Thanks for any suggestions.

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  • Combine multiple rows into one

    - by Jim
    I am trying to combine multiple rows of data into one. Column A contains the value on which the groupings will be based -- rows whose Column A values match will be combined into one row. My range extends from column A through X so I need a matching row of data to start in column Y. Example: +--------------+ ¦ 1001 ¦ A ¦ C ¦ ¦ 1001 ¦ B ¦ D ¦ ¦ 1002 ¦ A ¦ E ¦ ¦ 1002 ¦ B ¦ F ¦ ¦ 1002 ¦ C ¦ G ¦ +--------------+ Desired Result: +------------------------------+ ¦ 1001 ¦ A ¦ C ¦ B ¦ D ¦ ¦ ¦ ¦ 1002 ¦ A ¦ E ¦ B ¦ F ¦ C ¦ G ¦ +------------------------------+ The VBA code I am currently using is not taking the entire contents of the matched row. It is only taking the data in the 2nd column and moving it up. VBA Code: Sub Mergeitems() Dim cl As Range Dim rw As Range Set rw = ActiveCell Do While rw <> "" ' for each row in data set ' find first empty cell on row Set cl = rw.Offset(0, 1) Do While cl <> "" Set cl = cl.Offset(0, 1) Loop ' if next row needs to be processed... Do While rw = rw.Offset(1, 0) cl = rw.Offset(1, 1) ' move the data Set cl = cl.Offset(0, 1) ' update pointer to next blank cell rw.Offset(1, 0).EntireRow.Delete xlShiftUp ' delete old data Loop ' next row Set rw = rw.Offset(1, 0) Loop End Sub

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  • FreeBSD jail IMAP/MTA config recommendations

    - by kobame
    I've got access to my "own" FreeBSD jail. The jail has only basic, unconfigured system, but I have full access to FreeBSD ports, and (jail)root too. Now I need to setup my jail as IMAP/MTA. The question: What packages are EASIEST for config and later administration, (the simplest possible setup, with the minimum needed configuration) when: i haven't any preferences (don't know any yet) my (one) domain is managed by ISP, so don't need DNS need only IMAP for few users (up to 20 mailboxes) need secure transport layer (IMAPS/993) password auth, no LDAP, no kerberos, nor databases, nothing like fancy things... need easy-setup easy-admin MTA, with simplest possible password SMTP auth, (again no LDAP, nor DB), secure transport layer but would be nice have virus-scan and some anti-spam protection So, what ports I should install for MTA and IMAP? MTA (Sendmail, Postfix, Exim)? antivirus (ClamAV) antispam??? IMAP(S), (Dovecot, Courier) when the main criteria are: easy setup, and easy administration. When I googled I found only complicated setups for thousands of users with LDAP, databases and so on - too big-caliber for my small (easy?) needs. Any pointer to an easy howto is very welcomed.

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  • need to bring back win 7

    - by user290513
    I like making music and playing games and occasionally do some Photoshop. I had a windows 8 computer but my mouse pointer always got stuck, so to try out something new I installed Ubuntu. here is how I installed it: Went to advanced statup options clicked on "use a device" after plugging in my bootable USB with Ubuntu replaced my windows 8 and installed Ubuntu 14.04 LTS I hope I did it correctly though. So after a few months I could've really find out a good Audio Production (not LMMS, because I use Stagelight) software nor something that could be familiar to the UI of Photoshop. So I decided to bring back Windows, but because of the bad experience of 8 I thought about bringing back win 7 So I used an app named WinUSB to make my bootable USB drive after formatting it to NTFS in GParted But when I go to my grub menu, my USB doesn't show up and my PC being a UEFI device. I don't know how to get to the bios of my device. Can somebody tell how to install Windows 7 completely and deleting Ubuntu or at least give me a link to a tutorial. I have a netbook: it is an Acer Aspire One 725. I'm fine with using commands in terminal and another thing that my laptop doesn't have a CD drive or reader, I can't put a CD inside

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  • Why does pulling the power cord then pressing the power button fix a non-booting PC?

    - by sidewaysmilk
    I've been working at this institution for about 6 years. One thing thing that I've always found curious is that sometimes—especially after a power outage—we find a PC that won't boot when the power button is pressed. Usually, the fans will spin up, but it won't POST. Our solution is to pull the power cord, press the power button with the computer unplugged, then plug it in and turn it on. It seems more common with Gateway brand PCs than the Dells or HPs that we have around. Does anybody know what pressing the power button does when the computer is unplugged? I have some vague notion that closing the power button circuit allows some capacitors to discharge or something, but I'd like a firmer answer to offer my users when they ask me what I'm doing. My best guess as to why fans can spin but it can't POST is that the BIOS is in some non-functional state. I don't know how BIOS stores state, but my best guess is that there is some residual garbage in its registers or something, like the stack pointer isn't starting at 0 maybe?

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  • Windows 7 / TCP/IP network share guide - looking for to resolve failure to mount lacie network drive but works on XP,Linux,Mac.

    - by Rob
    Can anyone advise me of a really good, readable, Windows 7 TCP/IP network share guide, book, or reference. I want this because I cannot mount my Lacie 2big ethernet network drive in Windows 7 (32 bit home), but I can mount it in Windows XP Home 32bit, Ubuntu Linux 10.04 and Apple MacOS X. This drive is being mounted via the accompanying Lacie Ethernet Agent in XP (which I believe uses "Bonjour" protocol), on Mac and Linux it works without further need for software. Another Super User user has the same problem, but no answer: Trouble accessing network drives in Windows 7 I hope my take on the question shows a better willingness to investigate and do some digging - and therefore invite some suggestions to help with this. The drive is detected by Windows 7 (i.e. speech bubble "network drive found") but on trying to open an Explorer window, this remains blank with the Windows busy pointer. I'd prefer not to reinstall Windows 7 to see if that cures the problem, I'd rather understand what is happening/not happening, perhaps even compare differences with Windows XP. Suggestions, please for such guides or even the original problem itself. Update Edit Rewrote question more comprehensively here: Mhttp://superuser.com/questions/304209/looking-for-definitive-answer-to-accessing-a-network-share-via-windows-7-home-and

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  • Sudden "No Signal" in HDMI-DVI connection

    - by nazikus
    Yesterday I have connected external display Asus VW192C to my laptop Dell XPS 14-L421X via HDMI-to-DVI-D cable. And it worked perfectly fine from start. The day after, Asus screen went blank showing "No signal". Every time I connection/disconnection cable or power off/on the display it says "No signal". And I didn't change any system configurations meanwhile. To troubleshoot the problem, I have tried to connect laptop to TV (hdmi-to-hdmi) - it was fine. I've tried to connect a different laptop to the display via the same cable - worked fine as well. So its obviously something on system level, either Windows or graphics drivers. Also it seems that Windows still see the external display (I can move mouse pointer away from the main screen in Extended mode), but there's just no signal. Any ideas? What else to try? PS. My laptop has 2 graphics cards - GeForce 630M and Intel HD 4000 using NVidia Optimus technology. I have updated to latest Intel and NVidia drivers, still didn't help. PPS. Although I shouldn't have updated (from Intel support): "our Intel generic graphics drivers from the Intel website do not support using both Intel Graphics 4000 and NVidia GeForece GT630M". Nevertheless, it should not affect connectivity to additional display.

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  • Driver corruption when deploying Dell Touchpad Drivers (with software) during imaging process

    - by BigHomie
    We're an sccm shop, and use it to deploy Windows. When deploying Dell laptops (multiple models), the touchpad drivers seem install properly, but the software doesn't. The resulting problem is that when the touchpad is pressed on occasion, the mouse pointer will 'jump' to certain points on the screen. A possible symptom of this problem/visible sign is if the touchpad icon isn't in the system tray. The software is in the control panel, but when opened part of the gui is pixelated, indicating botched install maybe? The manual resolution to this, is to go into device manager and uninstall the driver with the option to uninstall all driver software. After a restart, the driver and software is apparently reinstalled, and from there works as expected. Obviously this partially defeats the purpose of a zero touch deployment. If anyone knows why this is and/or a possible workaround, those answers would be valid as well. Barring that, I want to find a way to deploy the driver and touchpad software in an unattended way, so that it can be conditionally installing during the imaging process. To be honest I'm not sure how to troubleshoot this, I suppose I could try drvinst.exe to install the driver, but finding out why this fails initially would keep me from spinning my wheels.

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  • Windows 7, Black screen with cursor, impossible to logon

    - by PJC
    First - I have gone through as many possible solutions I've found here and elsewhere. [Edit - to describe the issue in more detail, the PC appears to boot correctly, but instead of the logon screen, I have been getting a black screen WITH the pointer cursor, and it responds correctly to the mouse. Pressing CTL-ALT-DEL brings up the logon screen's background, but with no logon area nor any other content. This screen was at the full resolution before I uninstalled the graphics driver in safe-mode.] I also just ran a full up-to-date AVG scan from boot media. [Edit - the AVG scan, which was updated to today's virus signatures, found no issues at all.] So - steps I've tried: Safe Boot, Restore from before the issue - done, no help. Uninstall the graphics driver - done, now i have a 1024x768 fallback screen, still no way in. sfc /scannow - only doable from Safe boot obviously, but no change. [Edit - booting from restore media, performing a startup repair and...]Restore further back - restored to 2 days ago, and I'd had many reboots since then with no problem. Enable autologin to try to get beyond the login screen - done, doesn't work. It seems the best advice is complete reinstall, but I really don't want to do that because it'll take 3-4 days to add all the apps I use. Some key points to note - in both states - before and after removing the video driver, I always had a mouse cursor on the screen. CTL-ALT-DEL flashes up the login background, but no login info. I can (and often do) reinstall from scratch, but was at a fairly stable state before this, and would prefer not to. -Paul

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  • 64-bit Windows 7 gets stuck on logo screen on bootup

    - by Richard B
    I've had a PC running Windows 7 in my office which I'm not using at the moment (cause I'm working elsewhere as a consultant atm), I'm only accessing the PC using Team Viewer (http://www.teamviewer.com/) which means the PC has been running for quite some time now. I've restarted it maybe twice a week though. A few days ago I couldn't access it using Team Viewer and when I got to the office the screen was black with only the mouse pointer showing. The PC has four hard disks, three of them (all 1Tb) is using RAID 5. This is what I've done so far: I reboot and everything seems to load correctly. I get to a screen that gives me two choices - boot Windows normally or perform a startup repair. Choosing to boot Windows only gets me to the Windows 7 logo screen which only animates over and over again. Choosing to repair gets me to the repair screen that "checks for problems" and then it gets stuck on the "Attempting repairs..."-screen (I let it run for about 24 hours before giving up). What is the next step to take? I don't have any backups and no system restore points saved. I can access files and folders through a terminal window using a Windows 7 DVD so I guess nothing is lost yet... Please help me, thanks!

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  • Compiz and Desktop Effects on Netbook with External Monitor

    - by Nerdfest
    I have an Acer Aspire One AO150 and am having trouble plugging in an external monitor under Ubuntu 9.10. There were no problems under 9.04. If I plug in an external monitor once the machine is already up, then bring up the 'display' application to activate it, it basically hangs. There are no problem under these circumstances if I have desktop effects turned off. I've seen a few mentions of this problem on the Ubuntu forums, but never a solid solution. Any ideas? A few more details after a question below. The machine does not respond to its keyboard commands to switch to an external monitor, nor does it respond to Ctrl-Alt-F1, etc to switch out of X. The pointer is visible on the monitors (at the edge of each) and is frozen as a 'busy' cursor, but with no animation. The kernel does respond to SysReq commands (REISUB). In the latest attempt I had the external monitor active earlier, then removed it and activated desktop effects. Upon plugging in the eternal monitor then bringing up the display application, it hangs.

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  • Faster caching method

    - by pataroulis
    I have a service that provides HTML code which at some point it is not updated anymore. The code is always generated dynamically from a database with 10 million entries so each HTML code page rendering searches there for say 60 or 70 of those entries and then renders the page. So, for those expired pages, I want to use a caching system which will be VERY simple (like just enter a record with the rendered HTML and (if I need) remove it). I tried to do it file-based but the search for the existence of a file and then passing it through php to actually render it , seems like too much for what I want to do. I was thinking of doing it on mysql with a table with MEDIUMBLOBs (each page is around 100k). It would hold about 150000 such records (for now, at least). My question is: Would it be faster to let mysql do the lookup of the file and the passing to php or is the file-based approach faster? The lookup code for the file based version looks like this: $page = @file_get_contents(getCacheFilename($pageId)); if($page!=NULL) { echo $page; } else { renderAndCachePage($pageId); } which does one lookup whether it finds the file or not. The mysql table would just have an ID (the page id) and the blob entry. The disk of the system is a simple SATA raid 1 , the mysql daemon can grab up to 2.5GB of memory (i have a proxy running too, eating the rest of the 16GB of the machine. ) In general the disk is quite busy already. My not using PEAR cache, is because I think (please feel free to correct me on this) it adds overhead I do not need because the page rendering code is called about 2M times per day and I wouldn't want to go through the whole code each time (and yes, I have eaccelerator to cache the code too). Any pointer to what direction I should go, would be greatly welcome. Thanks!

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  • Duplicate monitor on highest resolution in Windows 7

    - by AlexanderMP
    I have a monitor with a native resolution of 2560x1440, connected through display port. I also have an AV Receiver connected to the video card via HDMI, to have surround sound in games. All using Radeon HD 5670 (will upgrade soon to HD 7850). The problem is that my computer detects the receiver as a separate monitor, with the highest available resolution of 1920x1080. I have 3 options: Disconnect the second display. But then the sound (digital audio output through video card) also disappears. Duplicate displays. But then my primary monitor resolution is reduced to a maximum of just 1920x1080, that being the maximum of the second monitor. Extend desktop. This is the solution I picked so far, it being the least evil. The problems I face in this situations are 2: I have a blank part of the desktop where I sometimes lose my mouse pointer, so I made the extension small, 640x480, and placed it in a corner; when I turn off the main display, all windows resize to 640x480. In Kubuntu I had the option to duplicate the displays, while keeping the higher resolution. Which was great. I tried overriding using the Win7 netbook hack, but it's not available on non-netbooks. Is there a similar solution for this problem in Windows 7?

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  • Monitor programs accessing my keyboard?

    - by Anti Earth
    As of a few days ago, my computer is behaving 'erratically'. When I am typing, my pointer will randomly move to another place in the text and start typing a semi-random string of characters. ("gvyfn" is common; It has typed this about 8 times whilst I composed all the text above) It often highlights part of or all the text and overwrites it. It sometimes goes into loops of pressing Control-alt-delete down, bringing up Windows 7 menu thing. It sometimes even messes with mouseclicks; they have unexpected results, like requesting admin priveledges from applications, instead of switching to their window. I believe this is because it is holding a alt-function key down. This behaviour happens periodically, in waves. It might subside for an hour, then continue to haunt me. I believe it to be a virus or malicious program. My anti-virus (Symantec) and multiply MS rootkit removers could not find anything suspicious. I've noticed that sometimes it re-maps keys, and types gibberish when I press certain keys (though no pattern is evident). I believe a malicious program has installed a keyhook on my computer. I'm wondering... - Is there a way to let me view which programs are emulating keystrokes? - Is there a way to view what keyboard hooks are installed? (I'm also at liberty to try any other techniques to remove this blasted thing. It is easily the most fustrating computer problem I've encountered). Thanks!

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  • Notepad++ FTP best solution

    - by yoda
    Hi, I use Notepad++ for more than 2 years now, and there's only 1 thing that it needs for me to be perfect: a actually-working-ftp-plugin. It has an ftp plugin, written by someone that meanwhile left the project (by meanwhile I mean a long time ago), and since then nobody had courage to improve it. The problem is that it does't handle connections very well. Sometimes it lost connection with the server and literally "blocks", others don't save the files properly, other only load half of the ftp files, etc etc .. My question is: Is there a way to use ftp and notepad++ (without using its build-in ftp or a ftp client like filezilla)? I've tried using NetDrive, but it gets stuck sometimes (makes the editor crash), and everytime the temporary file is refreshed by windows / NetDrive, it will load the new file without asking and skip the pointer to the end of the file (very very very annoying). In case you know how to make the built-in notepad++ ftp plugin work at 100%, I'd be much more happy! I'd like to have some feedback from you guys :) (I'm using Windows Vista) Thanks in advance!

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  • Auto-focus xdvi after running viewdvi in Emacs with AUCTeX.

    - by D Connors
    I've been using emacs with AUCTeX mode to edit my latex documents for a few days now, but there's something that's really bugging me. As it should be, whenever I do C-c C-c RET it compiles the file, and if repeat the command it views the output in xdvi. It's also set to the mini-mode TeX-source-specials-mode, so instead of opening a new window in xdvi it only reloads the window that's already open, brings it to the front, and sends me to wherever the pointer was in emacs (forward search). Now here's the problem: Even though the xdvi window is brought to the front, it's not focused. Instead, the emacs windows stays with focus (and that's where any keyboard input goes). And I keep forgetting about that, which leads me to accidentally editing the source file while trying to navigate in xdvi. Not to mention I'm forced to alt-tab in order to focus xdvi, and alt-tab twice if I just want to get back to emacs. Is there a way around this problem? I just want xdvi to be focused whenever I run the view command from emacs.

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  • C#: System.Collections.Concurrent.ConcurrentQueue vs. Queue

    - by James Michael Hare
    I love new toys, so of course when .NET 4.0 came out I felt like the proverbial kid in the candy store!  Now, some people get all excited about the IDE and it’s new features or about changes to WPF and Silver Light and yes, those are all very fine and grand.  But me, I get all excited about things that tend to affect my life on the backside of development.  That’s why when I heard there were going to be concurrent container implementations in the latest version of .NET I was salivating like Pavlov’s dog at the dinner bell. They seem so simple, really, that one could easily overlook them.  Essentially they are implementations of containers (many that mirror the generic collections, others are new) that have either been optimized with very efficient, limited, or no locking but are still completely thread safe -- and I just had to see what kind of an improvement that would translate into. Since part of my job as a solutions architect here where I work is to help design, develop, and maintain the systems that process tons of requests each second, the thought of extremely efficient thread-safe containers was extremely appealing.  Of course, they also rolled out a whole parallel development framework which I won’t get into in this post but will cover bits and pieces of as time goes by. This time, I was mainly curious as to how well these new concurrent containers would perform compared to areas in our code where we manually synchronize them using lock or some other mechanism.  So I set about to run a processing test with a series of producers and consumers that would be either processing a traditional System.Collections.Generic.Queue or a System.Collection.Concurrent.ConcurrentQueue. Now, I wanted to keep the code as common as possible to make sure that the only variance was the container, so I created a test Producer and a test Consumer.  The test Producer takes an Action<string> delegate which is responsible for taking a string and placing it on whichever queue we’re testing in a thread-safe manner: 1: internal class Producer 2: { 3: public int Iterations { get; set; } 4: public Action<string> ProduceDelegate { get; set; } 5: 6: public void Produce() 7: { 8: for (int i = 0; i < Iterations; i++) 9: { 10: ProduceDelegate(“Hello”); 11: } 12: } 13: } Then likewise, I created a consumer that took a Func<string> that would read from whichever queue we’re testing and return either the string if data exists or null if not.  Then, if the item doesn’t exist, it will do a 10 ms wait before testing again.  Once all the producers are done and join the main thread, a flag will be set in each of the consumers to tell them once the queue is empty they can shut down since no other data is coming: 1: internal class Consumer 2: { 3: public Func<string> ConsumeDelegate { get; set; } 4: public bool HaltWhenEmpty { get; set; } 5: 6: public void Consume() 7: { 8: bool processing = true; 9: 10: while (processing) 11: { 12: string result = ConsumeDelegate(); 13: 14: if(result == null) 15: { 16: if (HaltWhenEmpty) 17: { 18: processing = false; 19: } 20: else 21: { 22: Thread.Sleep(TimeSpan.FromMilliseconds(10)); 23: } 24: } 25: else 26: { 27: DoWork(); // do something non-trivial so consumers lag behind a bit 28: } 29: } 30: } 31: } Okay, now that we’ve done that, we can launch threads of varying numbers using lambdas for each different method of production/consumption.  First let's look at the lambdas for a typical System.Collections.Generics.Queue with locking: 1: // lambda for putting to typical Queue with locking... 2: var productionDelegate = s => 3: { 4: lock (_mutex) 5: { 6: _mutexQueue.Enqueue(s); 7: } 8: }; 9:  10: // and lambda for typical getting from Queue with locking... 11: var consumptionDelegate = () => 12: { 13: lock (_mutex) 14: { 15: if (_mutexQueue.Count > 0) 16: { 17: return _mutexQueue.Dequeue(); 18: } 19: } 20: return null; 21: }; Nothing new or interesting here.  Just typical locks on an internal object instance.  Now let's look at using a ConcurrentQueue from the System.Collections.Concurrent library: 1: // lambda for putting to a ConcurrentQueue, notice it needs no locking! 2: var productionDelegate = s => 3: { 4: _concurrentQueue.Enqueue(s); 5: }; 6:  7: // lambda for getting from a ConcurrentQueue, once again, no locking required. 8: var consumptionDelegate = () => 9: { 10: string s; 11: return _concurrentQueue.TryDequeue(out s) ? s : null; 12: }; So I pass each of these lambdas and the number of producer and consumers threads to launch and take a look at the timing results.  Basically I’m timing from the time all threads start and begin producing/consuming to the time that all threads rejoin.  I won't bore you with the test code, basically it just launches code that creates the producers and consumers and launches them in their own threads, then waits for them all to rejoin.  The following are the timings from the start of all threads to the Join() on all threads completing.  The producers create 10,000,000 items evenly between themselves and then when all producers are done they trigger the consumers to stop once the queue is empty. These are the results in milliseconds from the ordinary Queue with locking: 1: Consumers Producers 1 2 3 Time (ms) 2: ---------- ---------- ------ ------ ------ --------- 3: 1 1 4284 5153 4226 4554.33 4: 10 10 4044 3831 5010 4295.00 5: 100 100 5497 5378 5612 5495.67 6: 1000 1000 24234 25409 27160 25601.00 And the following are the results in milliseconds from the ConcurrentQueue with no locking necessary: 1: Consumers Producers 1 2 3 Time (ms) 2: ---------- ---------- ------ ------ ------ --------- 3: 1 1 3647 3643 3718 3669.33 4: 10 10 2311 2136 2142 2196.33 5: 100 100 2480 2416 2190 2362.00 6: 1000 1000 7289 6897 7061 7082.33 Note that even though obviously 2000 threads is quite extreme, the concurrent queue actually scales really well, whereas the traditional queue with simple locking scales much more poorly. I love the new concurrent collections, they look so much simpler without littering your code with the locking logic, and they perform much better.  All in all, a great new toy to add to your arsenal of multi-threaded processing!

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  • Dependency Injection in ASP.NET MVC NerdDinner App using Ninject

    - by shiju
    In this post, I am applying Dependency Injection to the NerdDinner application using Ninject. The controllers of NerdDinner application have Dependency Injection enabled constructors. So we can apply Dependency Injection through constructor without change any existing code. A Dependency Injection framework injects the dependencies into a class when the dependencies are needed. Dependency Injection enables looser coupling between classes and their dependencies and provides better testability of an application and it removes the need for clients to know about their dependencies and how to create them. If you are not familiar with Dependency Injection and Inversion of Control (IoC), read Martin Fowler’s article Inversion of Control Containers and the Dependency Injection pattern. The Open Source Project NerDinner is a great resource for learning ASP.NET MVC.  A free eBook provides an end-to-end walkthrough of building NerdDinner.com application. The free eBook and the Open Source Nerddinner application are extremely useful if anyone is trying to lean ASP.NET MVC. The first release of  Nerddinner was as a sample for the first chapter of Professional ASP.NET MVC 1.0. Currently the application is updating to ASP.NET MVC 2 and you can get the latest source from the source code tab of Nerddinner at http://nerddinner.codeplex.com/SourceControl/list/changesets. I have taken the latest ASP.NET MVC 2 source code of the application and applied  Dependency Injection using Ninject and Ninject extension Ninject.Web.Mvc.Ninject &  Ninject.Web.MvcNinject is available at http://github.com/enkari/ninject and Ninject.Web.Mvc is available at http://github.com/enkari/ninject.web.mvcNinject is a lightweight and a great dependency injection framework for .NET.  Ninject is a great choice of dependency injection framework when building ASP.NET MVC applications. Ninject.Web.Mvc is an extension for ninject which providing integration with ASP.NET MVC.Controller constructors and dependencies of NerdDinner application Listing 1 – Constructor of DinnersController  public DinnersController(IDinnerRepository repository) {     dinnerRepository = repository; }  Listing 2 – Constrcutor of AccountControllerpublic AccountController(IFormsAuthentication formsAuth, IMembershipService service) {     FormsAuth = formsAuth ?? new FormsAuthenticationService();     MembershipService = service ?? new AccountMembershipService(); }  Listing 3 – Constructor of AccountMembership – Concrete class of IMembershipService public AccountMembershipService(MembershipProvider provider) {     _provider = provider ?? Membership.Provider; }    Dependencies of NerdDinnerDinnersController, RSVPController SearchController and ServicesController have a dependency with IDinnerRepositiry. The concrete implementation of IDinnerRepositiry is DinnerRepositiry. AccountController has dependencies with IFormsAuthentication and IMembershipService. The concrete implementation of IFormsAuthentication is FormsAuthenticationService and the concrete implementation of IMembershipService is AccountMembershipService. The AccountMembershipService has a dependency with ASP.NET Membership Provider. Dependency Injection in NerdDinner using NinjectThe below steps will configure Ninject to apply controller injection in NerdDinner application.Step 1 – Add reference for NinjectOpen the  NerdDinner application and add  reference to Ninject.dll and Ninject.Web.Mvc.dll. Both are available from http://github.com/enkari/ninject and http://github.com/enkari/ninject.web.mvcStep 2 – Extend HttpApplication with NinjectHttpApplication Ninject.Web.Mvc extension allows integration between the Ninject and ASP.NET MVC. For this, you have to extend your HttpApplication with NinjectHttpApplication. Open the Global.asax.cs and inherit your MVC application from  NinjectHttpApplication instead of HttpApplication.   public class MvcApplication : NinjectHttpApplication Then the Application_Start method should be replace with OnApplicationStarted method. Inside the OnApplicationStarted method, call the RegisterAllControllersIn() method.   protected override void OnApplicationStarted() {     AreaRegistration.RegisterAllAreas();     RegisterRoutes(RouteTable.Routes);     ViewEngines.Engines.Clear();     ViewEngines.Engines.Add(new MobileCapableWebFormViewEngine());     RegisterAllControllersIn(Assembly.GetExecutingAssembly()); }  The RegisterAllControllersIn method will enables to activating all controllers through Ninject in the assembly you have supplied .We are passing the current assembly as parameter for RegisterAllControllersIn() method. Now we can expose dependencies of controller constructors and properties to request injectionsStep 3 – Create Ninject ModulesWe can configure your dependency injection mapping information using Ninject Modules.Modules just need to implement the INinjectModule interface, but most should extend the NinjectModule class for simplicity. internal class ServiceModule : NinjectModule {     public override void Load()     {                    Bind<IFormsAuthentication>().To<FormsAuthenticationService>();         Bind<IMembershipService>().To<AccountMembershipService>();                  Bind<MembershipProvider>().ToConstant(Membership.Provider);         Bind<IDinnerRepository>().To<DinnerRepository>();     } } The above Binding inforamtion specified in the Load method tells the Ninject container that, to inject instance of DinnerRepositiry when there is a request for IDinnerRepositiry and  inject instance of FormsAuthenticationService when there is a request for IFormsAuthentication and inject instance of AccountMembershipService when there is a request for IMembershipService. The AccountMembershipService class has a dependency with ASP.NET Membership provider. So we configure that inject the instance of Membership Provider. When configuring the binding information, you can specify the object scope in you application.There are four built-in scopes available in Ninject:Transient  -  A new instance of the type will be created each time one is requested. (This is the default scope). Binding method is .InTransientScope()   Singleton - Only a single instance of the type will be created, and the same instance will be returned for each subsequent request. Binding method is .InSingletonScope()Thread -  One instance of the type will be created per thread. Binding method is .InThreadScope() Request -  One instance of the type will be created per web request, and will be destroyed when the request ends. Binding method is .InRequestScope() Step 4 – Configure the Ninject KernelOnce you create NinjectModule, you load them into a container called the kernel. To request an instance of a type from Ninject, you call the Get() extension method. We can configure the kernel, through the CreateKernel method in the Global.asax.cs. protected override IKernel CreateKernel() {     var modules = new INinjectModule[]     {         new ServiceModule()     };       return new StandardKernel(modules); } Here we are loading the Ninject Module (ServiceModule class created in the step 3)  onto the container called the kernel for performing dependency injection.Source CodeYou can download the source code from http://nerddinneraddons.codeplex.com. I just put the modified source code onto CodePlex repository. The repository will update with more add-ons for the NerdDinner application.

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  • Using jQuery and OData to Insert a Database Record

    - by Stephen Walther
    In my previous blog entry, I explored two ways of inserting a database record using jQuery. We added a new Movie to the Movie database table by using a generic handler and by using a WCF service. In this blog entry, I want to take a brief look at how you can insert a database record using OData. Introduction to OData The Open Data Protocol (OData) was developed by Microsoft to be an open standard for communicating data across the Internet. Because the protocol is compatible with standards such as REST and JSON, the protocol is particularly well suited for Ajax. OData has undergone several name changes. It was previously referred to as Astoria and ADO.NET Data Services. OData is used by Sharepoint Server 2010, Azure Storage Services, Excel 2010, SQL Server 2008, and project code name “Dallas.” Because OData is being adopted as the public interface of so many important Microsoft technologies, it is a good protocol to learn. You can learn more about OData by visiting the following websites: http://www.odata.org http://msdn.microsoft.com/en-us/data/bb931106.aspx When using the .NET framework, you can easily expose database data through the OData protocol by creating a WCF Data Service. In this blog entry, I will create a WCF Data Service that exposes the Movie database table. Create the Database and Data Model The MoviesDB database is a simple database that contains the following Movies table: You need to create a data model to represent the MoviesDB database. In this blog entry, I use the ADO.NET Entity Framework to create my data model. However, WCF Data Services and OData are not tied to any particular OR/M framework such as the ADO.NET Entity Framework. For details on creating the Entity Framework data model for the MoviesDB database, see the previous blog entry. Create a WCF Data Service You create a new WCF Service by selecting the menu option Project, Add New Item and selecting the WCF Data Service item template (see Figure 1). Name the new WCF Data Service MovieService.svc. Figure 1 – Adding a WCF Data Service Listing 1 contains the default code that you get when you create a new WCF Data Service. There are two things that you need to modify. Listing 1 – New WCF Data Service File using System; using System.Collections.Generic; using System.Data.Services; using System.Data.Services.Common; using System.Linq; using System.ServiceModel.Web; using System.Web; namespace WebApplication1 { public class MovieService : DataService< /* TODO: put your data source class name here */ > { // This method is called only once to initialize service-wide policies. public static void InitializeService(DataServiceConfiguration config) { // TODO: set rules to indicate which entity sets and service operations are visible, updatable, etc. // Examples: // config.SetEntitySetAccessRule("MyEntityset", EntitySetRights.AllRead); // config.SetServiceOperationAccessRule("MyServiceOperation", ServiceOperationRights.All); config.DataServiceBehavior.MaxProtocolVersion = DataServiceProtocolVersion.V2; } } } First, you need to replace the comment /* TODO: put your data source class name here */ with a class that represents the data that you want to expose from the service. In our case, we need to replace the comment with a reference to the MoviesDBEntities class generated by the Entity Framework. Next, you need to configure the security for the WCF Data Service. By default, you cannot query or modify the movie data. We need to update the Entity Set Access Rule to enable us to insert a new database record. The updated MovieService.svc is contained in Listing 2: Listing 2 – MovieService.svc using System.Data.Services; using System.Data.Services.Common; namespace WebApplication1 { public class MovieService : DataService<MoviesDBEntities> { public static void InitializeService(DataServiceConfiguration config) { config.SetEntitySetAccessRule("Movies", EntitySetRights.AllWrite); config.DataServiceBehavior.MaxProtocolVersion = DataServiceProtocolVersion.V2; } } } That’s all we have to do. We can now insert a new Movie into the Movies database table by posting a new Movie to the following URL: /MovieService.svc/Movies The request must be a POST request. The Movie must be represented as JSON. Using jQuery with OData The HTML page in Listing 3 illustrates how you can use jQuery to insert a new Movie into the Movies database table using the OData protocol. Listing 3 – Default.htm <!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd"> <html xmlns="http://www.w3.org/1999/xhtml"> <head> <title>jQuery OData Insert</title> <script src="http://ajax.microsoft.com/ajax/jquery/jquery-1.4.2.js" type="text/javascript"></script> <script src="Scripts/json2.js" type="text/javascript"></script> </head> <body> <form> <label>Title:</label> <input id="title" /> <br /> <label>Director:</label> <input id="director" /> </form> <button id="btnAdd">Add Movie</button> <script type="text/javascript"> $("#btnAdd").click(function () { // Convert the form into an object var data = { Title: $("#title").val(), Director: $("#director").val() }; // JSONify the data var data = JSON.stringify(data); // Post it $.ajax({ type: "POST", contentType: "application/json; charset=utf-8", url: "MovieService.svc/Movies", data: data, dataType: "json", success: insertCallback }); }); function insertCallback(result) { // unwrap result var newMovie = result["d"]; // Show primary key alert("Movie added with primary key " + newMovie.Id); } </script> </body> </html> jQuery does not include a JSON serializer. Therefore, we need to include the JSON2 library to serialize the new Movie that we wish to create. The Movie is serialized by calling the JSON.stringify() method: var data = JSON.stringify(data); You can download the JSON2 library from the following website: http://www.json.org/js.html The jQuery ajax() method is called to insert the new Movie. Notice that both the contentType and dataType are set to use JSON. The jQuery ajax() method is used to perform a POST operation against the URL MovieService.svc/Movies. Because the POST payload contains a JSON representation of a new Movie, a new Movie is added to the database table of Movies. When the POST completes successfully, the insertCallback() method is called. The new Movie is passed to this method. The method simply displays the primary key of the new Movie: Summary The OData protocol (and its enabling technology named WCF Data Services) works very nicely with Ajax. By creating a WCF Data Service, you can quickly expose your database data to an Ajax application by taking advantage of open standards such as REST, JSON, and OData. In the next blog entry, I want to take a closer look at how the OData protocol supports different methods of querying data.

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  • Creating packages in code - Package Configurations

    Continuing my theme of building various types of packages in code, this example shows how to building a package with package configurations. Incidentally it shows you how to add a variable, and a connection too. It covers the five most common configurations: Configuration File Indirect Configuration File SQL Server Indirect SQL Server Environment Variable  For a general overview try the SQL Server Books Online Package Configurations topic. The sample uses a a simple helper function ApplyConfig to create or update a configuration, although in the example we will only ever create. The most useful knowledge is the configuration string (Configuration.ConfigurationString) that you need to set. Configuration Type Configuration String Description Configuration File The full path and file name of an XML configuration file. The file can contain one or more configuration and includes the target path and new value to set. Indirect Configuration File An environment variable the value of which contains full path and file name of an XML configuration file as per the Configuration File type described above. SQL Server A three part configuration string, with each part being quote delimited and separated by a semi-colon. -- The first part is the connection manager name. The connection tells you which server and database to look for the configuration table. -- The second part is the name of the configuration table. The table is of a standard format, use the Package Configuration Wizard to help create an example, or see the sample script files below. The table contains one or more rows or configuration items each with a target path and new value. -- The third and final part is the optional filter name. A configuration table can contain multiple configurations, and the filter is  literal value that can be used to group items together and act as a filter clause when configurations are being read. If you do not need a filter, just leave the value empty. Indirect SQL Server An environment variable the value of which is the three part configuration string as per the SQL Server type described above. Environment Variable An environment variable the value of which is the value to set in the package. This is slightly different to the other examples as the configuration definition in the package also includes the target information. In our ApplyConfig function this is the only example that actually supplies a target value for the Configuration.PackagePath property. The path is an XPath style path for the target property, \Package.Variables[User::Variable].Properties[Value], the equivalent of which can be seen in the screenshot below, with the object being our variable called Variable, and the property to set is the Value property of that variable object. The configurations as seen when opening the generated package in BIDS: The sample code creates the package, adds a variable and connection manager, enables configurations, and then adds our example configurations. The package is then saved to disk, useful for checking the package and testing, before finally executing, just to prove it is valid. There are some external resources used here, namely some environment variables and a table, see below for more details. namespace Konesans.Dts.Samples { using System; using Microsoft.SqlServer.Dts.Runtime; public class PackageConfigurations { public void CreatePackage() { // Create a new package Package package = new Package(); package.Name = "ConfigurationSample"; // Add a variable, the target for our configurations package.Variables.Add("Variable", false, "User", 0); // Add a connection, for SQL configurations // Add the SQL OLE-DB connection ConnectionManager connectionManagerOleDb = package.Connections.Add("OLEDB"); connectionManagerOleDb.Name = "SQLConnection"; connectionManagerOleDb.ConnectionString = "Provider=SQLOLEDB.1;Data Source=(local);Initial Catalog=master;Integrated Security=SSPI;"; // Add our example configurations, first must enable package setting package.EnableConfigurations = true; // Direct configuration file, see sample file this.ApplyConfig(package, "Configuration File", DTSConfigurationType.ConfigFile, "C:\\Temp\\XmlConfig.dtsConfig", string.Empty); // Indirect configuration file, the emvironment variable XmlConfigFileEnvironmentVariable // contains the path to the configuration file, e.g. C:\Temp\XmlConfig.dtsConfig this.ApplyConfig(package, "Indirect Configuration File", DTSConfigurationType.IConfigFile, "XmlConfigFileEnvironmentVariable", string.Empty); // Direct SQL Server configuration, uses the SQLConnection package connection to read // configurations from the [dbo].[SSIS Configurations] table, with a filter of "SampleFilter" this.ApplyConfig(package, "SQL Server", DTSConfigurationType.SqlServer, "\"SQLConnection\";\"[dbo].[SSIS Configurations]\";\"SampleFilter\";", string.Empty); // Indirect SQL Server configuration, the environment variable "SQLServerEnvironmentVariable" // contains the configuration string e.g. "SQLConnection";"[dbo].[SSIS Configurations]";"SampleFilter"; this.ApplyConfig(package, "Indirect SQL Server", DTSConfigurationType.ISqlServer, "SQLServerEnvironmentVariable", string.Empty); // Direct environment variable, the value of the EnvironmentVariable environment variable is // applied to the target property, the value of the "User::Variable" package variable this.ApplyConfig(package, "EnvironmentVariable", DTSConfigurationType.EnvVariable, "EnvironmentVariable", "\\Package.Variables[User::Variable].Properties[Value]"); #if DEBUG // Save package to disk, DEBUG only new Application().SaveToXml(String.Format(@"C:\Temp\{0}.dtsx", package.Name), package, null); Console.WriteLine(@"C:\Temp\{0}.dtsx", package.Name); #endif // Execute package package.Execute(); // Basic check for warnings foreach (DtsWarning warning in package.Warnings) { Console.WriteLine("WarningCode : {0}", warning.WarningCode); Console.WriteLine(" SubComponent : {0}", warning.SubComponent); Console.WriteLine(" Description : {0}", warning.Description); Console.WriteLine(); } // Basic check for errors foreach (DtsError error in package.Errors) { Console.WriteLine("ErrorCode : {0}", error.ErrorCode); Console.WriteLine(" SubComponent : {0}", error.SubComponent); Console.WriteLine(" Description : {0}", error.Description); Console.WriteLine(); } package.Dispose(); } /// <summary> /// Add or update an package configuration. /// </summary> /// <param name="package">The package.</param> /// <param name="name">The configuration name.</param> /// <param name="type">The type of configuration</param> /// <param name="setting">The configuration setting.</param> /// <param name="target">The target of the configuration, leave blank if not required.</param> internal void ApplyConfig(Package package, string name, DTSConfigurationType type, string setting, string target) { Configurations configurations = package.Configurations; Configuration configuration; if (configurations.Contains(name)) { configuration = configurations[name]; } else { configuration = configurations.Add(); } configuration.Name = name; configuration.ConfigurationType = type; configuration.ConfigurationString = setting; configuration.PackagePath = target; } } } The following table lists the environment variables required for the full example to work along with some sample values. Variable Sample value EnvironmentVariable 1 SQLServerEnvironmentVariable "SQLConnection";"[dbo].[SSIS Configurations]";"SampleFilter"; XmlConfigFileEnvironmentVariable C:\Temp\XmlConfig.dtsConfig Sample code, package and configuration file. ConfigurationApplication.cs ConfigurationSample.dtsx XmlConfig.dtsConfig

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  • Displaying an image on a LED matrix with a Netduino

    - by Bertrand Le Roy
    In the previous post, we’ve been flipping bits manually on three ports of the Netduino to simulate the data, clock and latch pins that a shift register expected. We did all that in order to control one line of a LED matrix and create a simple Knight Rider effect. It was rightly pointed out in the comments that the Netduino has built-in knowledge of the sort of serial protocol that this shift register understands through a feature called SPI. That will of course make our code a whole lot simpler, but it will also make it a whole lot faster: writing to the Netduino ports is actually not that fast, whereas SPI is very, very fast. Unfortunately, the Netduino documentation for SPI is severely lacking. Instead, we’ve been reliably using the documentation for the Fez, another .NET microcontroller. To send data through SPI, we’ll just need  to move a few wires around and update the code. SPI uses pin D11 for writing, pin D12 for reading (which we won’t do) and pin D13 for the clock. The latch pin is a parameter that can be set by the user. This is very close to the wiring we had before (data on D11, clock on D12 and latch on D13). We just have to move the latch from D13 to D10, and the clock from D12 to D13. The code that controls the shift register has slimmed down considerably with that change. Here is the new version, which I invite you to compare with what we had before: public class ShiftRegister74HC595 { protected SPI Spi; public ShiftRegister74HC595(Cpu.Pin latchPin) : this(latchPin, SPI.SPI_module.SPI1) { } public ShiftRegister74HC595(Cpu.Pin latchPin, SPI.SPI_module spiModule) { var spiConfig = new SPI.Configuration( SPI_mod: spiModule, ChipSelect_Port: latchPin, ChipSelect_ActiveState: false, ChipSelect_SetupTime: 0, ChipSelect_HoldTime: 0, Clock_IdleState: false, Clock_Edge: true, Clock_RateKHz: 1000 ); Spi = new SPI(spiConfig); } public void Write(byte buffer) { Spi.Write(new[] {buffer}); } } All we have to do here is configure SPI. The write method couldn’t be any simpler. Everything is now handled in hardware by the Netduino. We set the frequency to 1MHz, which is largely sufficient for what we’ll be doing, but it could potentially go much higher. The shift register addresses the columns of the matrix. The rows are directly wired to ports D0 to D7 of the Netduino. The code writes to only one of those eight lines at a time, which will make it fast enough. The way an image is displayed is that we light the lines one after the other so fast that persistence of vision will give the illusion of a stable image: foreach (var bitmap in matrix.MatrixBitmap) { matrix.OnRow(row, bitmap, true); matrix.OnRow(row, bitmap, false); row++; } Now there is a twist here: we need to run this code as fast as possible in order to display the image with as little flicker as possible, but we’ll eventually have other things to do. In other words, we need the code driving the display to run in the background, except when we want to change what’s being displayed. Fortunately, the .NET Micro Framework supports multithreading. In our implementation, we’ve added an Initialize method that spins a new thread that is tied to the specific instance of the matrix it’s being called on. public LedMatrix Initialize() { DisplayThread = new Thread(() => DoDisplay(this)); DisplayThread.Start(); return this; } I quite like this way to spin a thread. As you may know, there is another, built-in way to contextualize a thread by passing an object into the Start method. For the method to work, the thread must have been constructed with a ParameterizedThreadStart delegate, which takes one parameter of type object. I like to use object as little as possible, so instead I’m constructing a closure with a Lambda, currying it with the current instance. This way, everything remains strongly-typed and there’s no casting to do. Note that this method would extend perfectly to several parameters. Of note as well is the return value of Initialize, a common technique to add some fluency to the API and enabling the matrix to be instantiated and initialized in a single line: using (var matrix = new LedMS88SR74HC595().Initialize()) The “using” in the previous line is because we have implemented IDisposable so that the matrix kills the thread and clears the display when the user code is done with it: public void Dispose() { Clear(); DisplayThread.Abort(); } Thanks to the multi-threaded version of the matrix driver class, we can treat the display as a simple bitmap with a very synchronous programming model: matrix.Set(someimage); while (button.Read()) { Thread.Sleep(10); } Here, the call into Set returns immediately and from the moment the bitmap is set, the background display thread will constantly continue refreshing no matter what happens in the main thread. That enables us to wait or read a button’s port on the main thread knowing that the current image will continue displaying unperturbed and without requiring manual refreshing. We’ve effectively hidden the implementation of the display behind a convenient, synchronous-looking API. Pretty neat, eh? Before I wrap up this post, I want to talk about one small caveat of using SPI rather than driving the shift register directly: when we got to the point where we could actually display images, we noticed that they were a mirror image of what we were sending in. Oh noes! Well, the reason for it is that SPI is sending the bits in a big-endian fashion, in other words backwards. Now sure you could fix that in software by writing some bit-level code to reverse the bits we’re sending in, but there is a far more efficient solution than that. We are doing hardware here, so we can simply reverse the order in which the outputs of the shift register are connected to the columns of the matrix. That’s switching 8 wires around once, as compared to doing bit operations every time we send a line to display. All right, so bringing it all together, here is the code we need to write to display two images in succession, separated by a press on the board’s button: var button = new InputPort(Pins.ONBOARD_SW1, false, Port.ResistorMode.Disabled); using (var matrix = new LedMS88SR74HC595().Initialize()) { // Oh, prototype is so sad! var sad = new byte[] { 0x66, 0x24, 0x00, 0x18, 0x00, 0x3C, 0x42, 0x81 }; DisplayAndWait(sad, matrix, button); // Let's make it smile! var smile = new byte[] { 0x42, 0x18, 0x18, 0x81, 0x7E, 0x3C, 0x18, 0x00 }; DisplayAndWait(smile, matrix, button); } And here is a video of the prototype running: The prototype in action I’ve added an artificial delay between the display of each row of the matrix to clearly show what’s otherwise happening very fast. This way, you can clearly see each of the two images being displayed line by line. Next time, we’ll do no hardware changes, focusing instead on building a nice programming model for the matrix, with sprites, text and hardware scrolling. Fun stuff. By the way, can any of my reader guess where we’re going with all that? The code for this prototype can be downloaded here: http://weblogs.asp.net/blogs/bleroy/Samples/NetduinoLedMatrixDriver.zip

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  • Pre-filtering and shaping OData feeds using WCF Data Services and the Entity Framework - Part 1

    - by rajbk
    The Open Data Protocol, referred to as OData, is a new data-sharing standard that breaks down silos and fosters an interoperative ecosystem for data consumers (clients) and producers (services) that is far more powerful than currently possible. It enables more applications to make sense of a broader set of data, and helps every data service and client add value to the whole ecosystem. WCF Data Services (previously known as ADO.NET Data Services), then, was the first Microsoft technology to support the Open Data Protocol in Visual Studio 2008 SP1. It provides developers with client libraries for .NET, Silverlight, AJAX, PHP and Java. Microsoft now also supports OData in SQL Server 2008 R2, Windows Azure Storage, Excel 2010 (through PowerPivot), and SharePoint 2010. Many other other applications in the works. * This post walks you through how to create an OData feed, define a shape for the data and pre-filter the data using Visual Studio 2010, WCF Data Services and the Entity Framework. A sample project is attached at the bottom of Part 2 of this post. Pre-filtering and shaping OData feeds using WCF Data Services and the Entity Framework - Part 2 Create the Web Application File –› New –› Project, Select “ASP.NET Empty Web Application” Add the Entity Data Model Right click on the Web Application in the Solution Explorer and select “Add New Item..” Select “ADO.NET Entity Data Model” under "Data”. Name the Model “Northwind” and click “Add”.   In the “Choose Model Contents”, select “Generate Model From Database” and click “Next”   Define a connection to your database containing the Northwind database in the next screen. We are going to expose the Products table through our OData feed. Select “Products” in the “Choose your Database Object” screen.   Click “Finish”. We are done creating our Entity Data Model. Save the Northwind.edmx file created. Add the WCF Data Service Right click on the Web Application in the Solution Explorer and select “Add New Item..” Select “WCF Data Service” from the list and call the service “DataService” (creative, huh?). Click “Add”.   Enable Access to the Data Service Open the DataService.svc.cs class. The class is well commented and instructs us on the next steps. public class DataService : DataService< /* TODO: put your data source class name here */ > { // This method is called only once to initialize service-wide policies. public static void InitializeService(DataServiceConfiguration config) { // TODO: set rules to indicate which entity sets and service operations are visible, updatable, etc. // Examples: // config.SetEntitySetAccessRule("MyEntityset", EntitySetRights.AllRead); // config.SetServiceOperationAccessRule("MyServiceOperation", ServiceOperationRights.All); config.DataServiceBehavior.MaxProtocolVersion = DataServiceProtocolVersion.V2; } } Replace the comment that starts with “/* TODO:” with “NorthwindEntities” (the entity container name of the Model we created earlier).  WCF Data Services is initially locked down by default, FTW! No data is exposed without you explicitly setting it. You have explicitly specify which Entity sets you wish to expose and what rights are allowed by using the SetEntitySetAccessRule. The SetServiceOperationAccessRule on the other hand sets rules for a specified operation. Let us define an access rule to expose the Products Entity we created earlier. We use the EnititySetRights.AllRead since we want to give read only access. Our modified code is shown below. public class DataService : DataService<NorthwindEntities> { public static void InitializeService(DataServiceConfiguration config) { config.SetEntitySetAccessRule("Products", EntitySetRights.AllRead); config.DataServiceBehavior.MaxProtocolVersion = DataServiceProtocolVersion.V2; } } We are done setting up our ODataFeed! Compile your project. Right click on DataService.svc and select “View in Browser” to see the OData feed. To view the feed in IE, you must make sure that "Feed Reading View" is turned off. You set this under Tools -› Internet Options -› Content tab.   If you navigate to “Products”, you should see the Products feed. Note also that URIs are case sensitive. ie. Products work but products doesn’t.   Filtering our data OData has a set of system query operations you can use to perform common operations against data exposed by the model. For example, to see only Products in CategoryID 2, we can use the following request: /DataService.svc/Products?$filter=CategoryID eq 2 At the time of this writing, supported operations are $orderby, $top, $skip, $filter, $expand, $format†, $select, $inlinecount. Pre-filtering our data using Query Interceptors The Product feed currently returns all Products. We want to change that so that it contains only Products that have not been discontinued. WCF introduces the concept of interceptors which allows us to inject custom validation/policy logic into the request/response pipeline of a WCF data service. We will use a QueryInterceptor to pre-filter the data so that it returns only Products that are not discontinued. To create a QueryInterceptor, write a method that returns an Expression<Func<T, bool>> and mark it with the QueryInterceptor attribute as shown below. [QueryInterceptor("Products")] public Expression<Func<Product, bool>> OnReadProducts() { return o => o.Discontinued == false; } Viewing the feed after compilation will only show products that have not been discontinued. We also confirm this by looking at the WHERE clause in the SQL generated by the entity framework. SELECT [Extent1].[ProductID] AS [ProductID], ... ... [Extent1].[Discontinued] AS [Discontinued] FROM [dbo].[Products] AS [Extent1] WHERE 0 = [Extent1].[Discontinued] Other examples of Query/Change interceptors can be seen here including an example to filter data based on the identity of the authenticated user. We are done pre-filtering our data. In the next part of this post, we will see how to shape our data. Pre-filtering and shaping OData feeds using WCF Data Services and the Entity Framework - Part 2 Foot Notes * http://msdn.microsoft.com/en-us/data/aa937697.aspx † $format did not work for me. The way to get a Json response is to include the following in the  request header “Accept: application/json, text/javascript, */*” when making the request. This is easily done with most JavaScript libraries.

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