Search Results

Search found 42218 results on 1689 pages for 'os version'.

Page 850/1689 | < Previous Page | 846 847 848 849 850 851 852 853 854 855 856 857  | Next Page >

  • Getting started with a new iMac...

    - by Moshe
    I'm on my first Apple computer, a shiny new 21.5" iMac. I am not unfamiliar with OS X as I have been using a borrowed MacBook for a few months. Considering that this is my machine, I am more comfortable "settling in". I would like to get recommendations for software to install on it, other possible uses and whatnot. I bought it primarily for iPhone development, but I make videos on my beast of a PC using Adobe Premiere CS3. What software is recommended for me to download for the aforementioned as well as photo editing, graphic design and web design? Bear in mind that this machine will NOT have steady internet access and that I'm looking for freeware only. THANKS!

    Read the article

  • synergy-plug is there some kind of log or error control?

    - by ufk
    Hiya. I configured synergy-plus server and client as described in the following url: http://www.engadget.com/2005/08/09/how-to-share-your-keyboard-and-mouse-in-realtime-with-synergy/ I didn't find any info indicating that there is a log file or any error control to see if the client connect correctly. how can i troubleshoot ? Trying to connect between Linux OS and Snow Leopard. this is my server configuration file: (music snow is the snow leopard, tux-in is the linux) section: screens tux-in.local: music-snow: end section: links tux-in.local: right = music-snow music-snow: left = tux-in.local end

    Read the article

  • 1Tb disk formatted on Linux won't mount on windows nor mac

    - by Pedro MC
    I have an external HD (western digital) with 1Tb. I use Linux but I wanted to reserve a cross platform partition on the disk. I decided to create two partitions and used the "disks" application to do it. I created one partition with the LUKS (version 1) encryption and the other one, cross platform, in NTFS filesystem. Things work fine on my OS but when I try to use the disk (the cross platform partition) on both windows and mac the device is not recognized. What could it be? Next, output of "sfdisk -l /dev/sdb": Disk /dev/sdb: 121600 cylinders, 255 heads, 63 sectors/track Units = cylinders of 8225280 bytes, blocks of 1024 bytes, counting from 0 Device Boot Start End #cyls #blocks Id System /dev/sdb1 0+ 36473- 36473- 292968750 83 Linux /dev/sdb2 36473+ 121600- 85128- 683789062+ 83 Linux /dev/sdb3 0 - 0 0 0 Empty /dev/sdb4 0 - 0 0 0 Empty

    Read the article

  • How to reset MacOsX while keeping BootCamp?

    - by ss814
    I have MacOsX 10.8.2 installed on my MacBook Pro and Windows 8 licenced on a BootCamp partition. I have messed up my MacOsx partition (problems while programming, .h files not found, old applications removed that still appears) and I wanna start back from a clean OS. Is there a Way to reset my partition (or reinstall, obviously) keeping my BootCamp partition safe ? I know I could use my recovery partition but I do not know if it won't delete my Windows and it no longer appears in disk utility. As I found no answers in the Internet, does someone how how to do that ? Thanks in advance.

    Read the article

  • Google I/O 2012 - OAuth 2.0 for Identity and Data Access

    Google I/O 2012 - OAuth 2.0 for Identity and Data Access Ryan Boyd Users like to keep their data in one place on the web where it's easily accessible. Whether it's YouTube videos, Google Drive files, Google contacts or one of many other types of data, users need a way to securely grant applications access to their data. OAuth is the key web standard for delegated data access and OAuth 2.0 is the next-generation version with additional security features. This session will cover the latest advances in how OAuth can be used for data access, but will also dive into how you can lower the barrier to entry for your application by allowing users to login using their Google accounts. You will learn, through an example written in Python, how to use OAuth 2.0 to incorporate user identity into your web application. Best practices for desktop applications, mobile applications and server-to-server use cases will also be discussed. From: GoogleDevelopers Views: 11 1 ratings Time: 58:56 More in Science & Technology

    Read the article

  • Lion refuses to be installed to any partitions on Mac

    - by Arafinwe
    I was attempting to install Lion on my MacBook 7-1, on which I have installed Ubuntu 10.04 on a separate partition. Currently, my partitions look like this: |-----Mac-----|-Grub-|----Ubuntu----|-Ubuntu Swap-|. However, Disk Utility (and I assume the rest of Mac OS X) sees it as |-----Mac-----|-----Unknown-----|. Note that I am using rEfit as my default bootloader. When attempting to install Lion, I am greeted by this screen: By the way, it appears that only the Grub partition is recognized, as I remember setting it to about 10 MB. Can anyone help with this?

    Read the article

  • Corrupt file indicative of corrupt hard drive?

    - by Elipsicon
    I have noticed that two files on my (almost full) 2 TB hard drive have been corrupted. One file has 20 kB (!) corrupted, i.e. consecutive 20 kB have changed, even though the modification date of the file hasn't changed and I haven't worked with this file for over a year. This tells me that something "below" the file system level has messed with the data and the only thing I can think of is hardware failure, most likely hard disk failure. I've tested my RAM already and it works flawlessly. I'm using ext4 on Linux, if that is of any help. Is this normal? Is it time to change my hard drive disk before something worse happens? What can I do to prevent that from happening in the future? Is there some built-in feature of, or extension to ext4 that includes additional error correcting code and/or watches files for changes that haven't been caused by the OS?

    Read the article

  • Bash color prompt and long commands

    - by Eric J.
    I'm colorizing parts of my bash prompt using ANSI escape sequences. This works great, until the command I'm currently typing in is long enough that it has to wrap. Instead of the rest of the command displaying on the next line, it wraps back to column 1 of the current line, overwriting the beginning of the prompt. I get that behavior with this prompt: export PS1="[\u][\033[0;32;40mdemo \033[0;33;40m1.5.40.b\033[0;37;40m] \w> \033[0m" but it works correctly with the same prompt, ANSI sequences remove: export PS1="[\u][demo 1.5.40.b] \w> " I'm connecting using the current version of Putty, with default Putty settings. The OS is Ubuntu 8.10.

    Read the article

  • How to comply with this guideline for submitting an application to the Software Center?

    - by George Edison
    I was reading through the Ubuntu Developer Programme Agreement for submitting applications to the Software Center and stubled across the following clause: 3.1 You must first test Apps you submit to confirm they are compatible with all currently supported versions of Ubuntu (as listed on Canonical's website at the date of submission by you) and your Apps must comply with the Publishing Policy. Does this mean I must install both the 32 and 64 bit versions of Ubuntu 8.04, 10.04, 10.10, 11.04, and 11.10? If so, that's 10 installations of Ubuntu - is that really feasible (even with virtual machines)? Alternatively, does anyone have suggestions for testing the application without actually installing each version? Some sort of chroot tool, perhaps?

    Read the article

  • Second partition with Windows 7 unmountable

    - by Florian Pilz
    I'm using GRUB2 to dualboot Ubuntu and Windows 7. I installed Windows 7 some days ago and rewrote GRUB2 to cope with the dualboot. Everything went fine till yesterday - I could boot into both OS. Since this morning my laptop restarts every time I choose Windows 7 from the menu. Ubuntu is still working. As I tried to mount the partition with Windows 7 on Ubuntu it gave me return code 2, so this isn't working as well. I tried to reinstall GRUB2 to the MBR but it didn't help. I also tried to repair Windows 7 boot with it's install DVD, while trying so it showed me the following error: "Status: 0xc000000f Info: Boot selection failed because a required device is inaccessible." Tanks in advance

    Read the article

  • SharePoint 2013 Development Machine - Now Available

    - by Sahil Malik
    SharePoint 2010 Training: more information With SharePoint 2013 RTM’ing, I am thrilled to announce an updated version of my SharePoint 2013 Development Machine book’let. As you know, I am publishing many small booklets, and eventually I will publishing a single big book also – sort of the track/cd model. Also, this self-e-publish model allows me to keep the content updated as I learn more. There is a very minor portion at the end that is still pre-RTM. Specifically as of now SharePoint Designer 2013 and Visual Studio tools for SharePoint 2013 have not yet RTM’ed. However, installing those is not very different from Beta2. The screenshots may change a bit. I will of course update the book soon as the RTM bits are available. Read full article ....

    Read the article

  • Data Warehouse Best Practices

    - by jean-pierre.dijcks
    In our quest to share our endless wisdom (ahem…) one of the things we figured might be handy is recording some of the best practices for data warehousing. And so we did. And, we did some more… We now have recreated our websites on Oracle Technology Network and have a separate page for best practices, parallelism and other cool topics related to data warehousing. But the main topic of this post is the set of recorded best practices. Here is what is available (and it is a series that ties together but can be read independently), applicable for almost any database version: Partitioning 3NF schema design for a data warehouse Star schema design Data Loading Parallel Execution Optimizer and Stats management The best practices page has a lot of other useful information so have a look here.

    Read the article

  • Firefox 4 : les extensions se mettront à jour automatiquement, mais pas le navigateur

    Firefox 4 : les extensions se mettront à jour automatiquement Mais pas le navigateur Mise à jour du 07/12/10 A mesure que le navigateur de la Fondation Mozilla enchaîne les betas (7 à ce jour - lire ci-avant), la version définitive de Firefox 4 se précise. Dernière nouveauté en date, dévoilée par Jenny Boriss, en charge de l'UI et de l'expérience utilisateur, la mise à jour automatique ? et silencieuse ? des extensions. Jusqu'ici, Mozilla avait fait le choix d'indiquer à l'utilisateur qu'une mise à jour était disponible pour tel ou tel add-on. Ce dernier pouvait alors choisir de l'appliquer ou non. Mieux, la beta 7 perm...

    Read the article

  • Expression Blend 4 available and training resources

    - by pluginbaby
    As you may know Expression Blend 4 has shipped! It is still part of Expression Studio, which now comes in 2 “flavors”: Expression Studio 4 Ultimate Expression Blend SketchFlow Expression Web + SuperPreview Expression Encoder Expression Design Expression Studio 4 Web Professional Expression Web + SuperPreview Expression Encoder Expression Design So the version you want for Silverlight is Expression Studio 4 Ultimate (because you can’t buy Expression Blend alone). Expression Blend is an awesome tool but might be difficult to approach at first, specially for people coming from Visual Studio… this tool target designers so it can takes time for a developer to get comfortable enough. Good news is the availability of a free “Blend Fundamentals Training” which contains plenty of resources to help you master Expression Blend in 5 days: http://www.microsoft.com/expression/resources/BlendTraining/   Also don’t forget the .toolbox: http://www.microsoft.com/design/toolbox/ This Microsoft website contains courses and tutorials to help you learn UI Design for Silverlight with Expression Blend.

    Read the article

  • How to prevent yourself from commenting on websites?

    - by MHH
    There is a bunch of browser add ons to either block particular websites (i.e. leechblock, chrome nanny or various OS specific solutions) or block the comment section of a website (i.e. commentBlocker). However, what if you want to be able to read the comment section of all websites, but want to never be able to add comments yourself, on particular sites? Is there anything that will allow this? I'm particularly interested in answers that will work for both windows and mac, and will also work for google chrome, firefox, and safari (note they can be different solutions for each browser/operating system)

    Read the article

  • Updated Technical Best Practices whitepaper

    - by ACShorten
    The Technical Best Practices whitepaper has been updated with the latest advice. This edition of the whitepaper covers advice from our internal management team from the product group that manages our environments. Our product teams manage over 1500+ copies of the product, covering every version, every platform and every phase of our development, testing and production product development cycle. The technical team managing that group of environments has compiled some additional advice that has been incorporated into the Technical Best Practices and other whitepapers (inclusding Performance Troubleshooting and the Software Configuration Management Series). New advice includes new installation advice, advanced settings, new security settings and advice for both Oracle WebLogic and IBM WebSphere installations. The Technical Best Practices whitepaper is available from My Oracle Support at Doc Id: 560367.1. To assist readers of past editions of the whitepaper, new or updated advice is marked with an appropriate graphic.

    Read the article

  • Only upgrading the kernel!

    - by Anwar Shah
    I have seen some people saying to install the kernel of Ubuntu 11.04 (probably 2.6.38..) to use on Ubuntu 10.04 (2.6.35...may be) to only be able to use a Wimax device driver without upgrading their whole Ubuntu System. I find in this method something wrong, but I cannot argue as they are saying that it is OK!!. I tried to insist to upgrade to the latest Ubuntu version with all the software. But I also have the question myself : Does upgrading only the kernel is Okay ? or in other words, Is it OK to have Hardy system with Precise kernel (by adding precise's repository and removing it after upgrade). What are the possible problems ?

    Read the article

  • Do Seagate Momentus XT SSD Hybrid drives perform better than a good hard drive + flash on ReadyBoost

    - by Chris W. Rea
    Seagate has released a product called the Momentus XT Solid State Hybrid Drive. At a glance, this looks exactly like what Windows ReadyBoost attempts to do with software at the OS level: Pairing the benefits of a large hard drive together with the performance of solid-state flash memory. Does the Momentus XT out-perform a similar ad-hoc pairing of a decent hard drive with similar flash memory storage under Windows ReadyBoost? Other than the obvious "a hardware implementation ought to be faster than a software implementation", why would ReadyBoost not be able to perform as well as such a hybrid device?

    Read the article

  • OSX: Selecting default application for all unknown and different file types (extensions)

    - by Leo
    I work in cluster computing and am using Mac OS X 10.6. I send off hundreds of computing jobs a day, and each one comes back with with a different extension. For example, svmGeneSelect.o12345 which is the std output of my svmGeneSelect job which is job number 12345. I don't control the extensions. All files are plain text. I want OSX to open any file extension that it hasn't seen before with my favorite text editor when I click on it. Or even better set up file association defaults for extension patterns ie textEdit for extensions matching *.o*. I do NOT want to create file associations for individual files since this extension will only ever exist once, and I do not want to go through the process of selecting the application to use for each file. Thanks for any help you can offer.

    Read the article

  • How I Work: A Cloud Developer's Workstation

    - by BuckWoody
    I've written here a little about how I work during the day, including things like using a stand-up desk (still doing that, by the way). Inspired by a Twitter conversation yesterday, I thought I might explain how I set up my computing environment. First, a couple of important points. I work in Cloud Computing, specifically (but not limited to) Windows Azure. Windows Azure has features to run a Virtual Machine (IaaS), run code without having to control a Virtual Machine (PaaS) and use databases, video streaming, Hadoop and more (a kind of SaaS for tech pros). As such, my designs run the gamut of on-premises, VM's in the Cloud, and software that I write for a platform. I focus on data primarily, meaning that I design a lot of systems that use an RDBMS (like SQL Server or Windows Azure Databases) or a NoSQL approach (MongoDB on Azure or large-scale Key-Value Pairs in Table storage) and even Hadoop and R, and also Cloud Numerics in F#. All that being said, those things inform my choices below. Hardware I have a Lenovo X220 tablet/laptop which I really like a great deal - it's a light, tough, extremely fast system. When I travel, that's the system I take. It has 8GB of RAM, and an SSD drive. I sometimes use that to develop or work at a client's site, on the road, or in the living room when I'm not in my home office. My main system is a GateWay DX430017 - I've maxed it out on RAM, and I have two 1TB drives in it. It's not only my workstation for work; I leave it on all the time and it streams our videos, music and books. I have about 3400 e-books, and I've just started using Calibre to stream the library. I run Windows 8 on it so I can set up Hyper-V images, since Windows Azure allows me to move regular Hyper-V disks back and forth to the Cloud. That's where all my "servers" are, when I have to use an IaaS approach. The reason I use a desktop-style system rather than a laptop only approach is that a good part of my job is setting up architectures to solve really big, complex problems. That means I have to simulate entire networks on-premises, along with the Hybrid Cloud approach I use a lot. I need a lot of disk space and memory for that, and I use two huge monitors on my stand-up desk. I could probably use 10 monitors if I had the room for them. Also, since it's our home system as well, I leave it on all the time and it doesn't travel.   Software For the software for my systems, it's important to keep in mind that I not only write code, but I design databases, teach, present, and create Linux and other environments. Windows 8 - While the jury is out for me on the new interface, the context-sensitive search, integrated everything, and speed is just hands-down the right choice. I've evaluated a server OS, Linux, even an Apple, but I just am not as efficient on those as I am with Windows 8. Visual Studio Ultimate - I develop primarily in .NET (C# and F# mostly) and I use the Team Foundation Server in the cloud, and I'm asked to do everything from UI to Services, so I need everything. Windows Azure SDK, Windows Azure Training Kit - I need the first to set up my Azure PaaS coding, and the second has all the info I need for PaaS, IaaS and SaaS. This is primarily how I get paid. :) SQL Server Developer Edition - While I might install Oracle, MySQL and Postgres on my VM's, the "outside" environment is SQL Server for an RDBMS. I install the Developer Edition because it has the same features as Enterprise Edition, and comes with all the client tools and documentation. Microsoft Office -  Even if I didn't work here, this is what I would use. I've just grown too accustomed to doing business this way to change, so my advice is always "use what works", and this does. The parts I use are: OneNote (and a Math Add-in) - I do almost everything - and I mean everything in OneNote. I can code, do high-end math, present, design, collaborate and more. All my notebooks are on my Skydrive. I can use them from any system, anywhere. If you take the time to learn this program, you'll be hooked. Excel with PowerPivot - Don't make that face. Excel is the world's database, and every Data Scientist I know - even the ones where I teach at the University of Washington - know it, use it, and love it.  Outlook - Primary communications, CRM and contact tool. I have all of my social media hooked up to it, so when I get an e-mail from you, I see everything, see all the history we've had on e-mail, find you on a map and more. Lync - I was fine with LiveMeeting, although it has it's moments. For me, the Lync client is tres-awesome. I use this throughout my day, present on it, stay in contact with colleagues and the folks on the dev team (who wish I didn't have it) and more.  PowerPoint - Once again, don't make that face. Whenever I see someone complaining about PowerPoint, I have 100% of the time found they don't know how to use it. If you suck at presenting or creating content, don't blame PowerPoint. Works great on my machine. :) Zoomit - Magnifier - On Windows 7 (and 8 as well) there's a built-in magnifier, but I install Zoomit out of habit. It enlarges the screen. If you don't use one of these tools (or their equivalent on some other OS) then you're presenting/teaching wrong, and you should stop presenting/teaching until you get them and learn how to show people what you can see on your tiny, tiny monitor. :) Cygwin - Unix for Windows. OK, that's not true, but it's mostly that. I grew up on mainframes and Unix (IBM and HP, thank you) and I can't imagine life without  sed, awk, grep, vim, and bash. I also tend to take a lot of the "Science" and "Development" and "Database" packages in it as well. PuTTY - Speaking of Unix, when I need to connect to my Linux VM's in Windows Azure, I want to do it securely. This is the tool for that. Notepad++ - Somewhere between torturing myself in vim and luxuriating in OneNote is Notepad++. Everyone has a favorite text editor; this one is mine. Too many features to name, and it's free. Browsers - I install Chrome, Firefox and of course IE. I know it's in vogue to rant on IE, but I tend to think for myself a great deal, and I've had few (none) problems with it. The others I have for the haterz that make sites that won't run in IE. Visio - I've used a lot of design packages, but none have the extreme meta-data edit capabilities of Visio. I don't use this all the time - it can be rather heavy, but what it does it does really well. I also present this way when I'm not using PowerPoint. Yup, I just bring up Visio and diagram away as I'm chatting with clients. Depending on what we're covering, this can be the right tool for that. Tweetdeck - The AIR one, not that new disaster they came out with. I live on social media, since you, dear readers, are my cube-mates. When I get tired of you all, I close Tweetdeck. When I need help or someone needs help from me, or if I want to see a picture of a cat while I'm coding, I bring it up. It's up most all day and night. Windows Media Player - I listen to Trance or Classical when I code, and I find music managers overbearing and extra. I just use what comes in the box, and it works great for me. R - F# and Cloud Numerics now allows me to load in R libraries (yay!) and I use this for statistical work on big data loads. Microsoft Math - One of the most amazing, free, rich, amazing, awesome, amazing calculators out there. I get the 64-bit version for quick math conversions, plots and formula-checks. Python - I know, right? Who knew that the scientific community loved Python so much. But they do. I use 2.7; not as much runs with 3+. I also use IronPython in Visual Studio, or I edit in Notepad++ Camstudio recorder - Windows PSR - In much of my training, and all of my teaching at the UW, I need to show a process on a screen. Camstudio records screen and voice, and it's free. If I need to make static training, I use the Windows PSR tool that's built right in. It's ostensibly for problem duplication, but I use it to record for training.   OK - your turn. Post a link to your blog entry below, and tell me how you set your system up.  

    Read the article

  • Capistrano deploying to different servers with different authentication methods

    - by marimaf
    I need to deploy to 2 different server and these 2 servers have different authentication methods (one is my university's server and the other is an amazon web server AWS) I already have running capistrano for my university's server, but I don't know how to add the deployment to AWS since for this one I need to add ssh options for example to user the .pem file, like this: ssh_options[:keys] = [File.join(ENV["HOME"], ".ssh", "test.pem")] ssh_options[:forward_agent] = true I have browsed starckoverflow and no post mention about how to deal with different authentication methods this and this I found a post that talks about 2 different keys, but this one refers to a server and a git, both usings different pem files. This is not the case. I got to this tutorial, but couldn't find what I need. I don't know if this is relevant for what I am asking: I am working on a rails app with ruby 1.9.2p290 and rails 3.0.10 and I am using an svn repository Please any help os welcome. Thanks a lot

    Read the article

  • Semi-random clicking sound from Macbook Pro

    - by Justin Love
    There is an occasional click sound coming from my Macbook Pro (17", 2.2 Ghz Core 2 Duo) I upgraded to Snow Leopard recently, but the computer was also in for service about week before that, so I can't be certain the OS upgrade is related. The sound has no set interval and frequency varies from rare to every few seconds. I can alleviate the sound by turning up the fan speed with smcFanControl. Turning the right fan up about half way seems to be sufficient. Unfortunately, turning up the left fan also causes the right to turn on, because the sound seems to be slightly more to the left. The cause seems to be either a fan or heat-related.

    Read the article

  • Dual boot Windows XP 32 bit and Windows 7 64-bit

    - by Santanu Roy
    My system config is AMD phenom-II x2 550 processor, 2x2gb(800fsb)ddr2 zion ram, gigabyte ga-m61pme-s2 motherboard, 160gb sata hdd. Now I am planning to install Windows XP sp3 (32-bit) and Windows 7 (64bit). My first questions are: Is my system enough for the above mentioned two OSes? Which OS one should be installed first on local disk c: drive? I have both XP and vista drivers on separate disks as provided with my motherboard but don't have drivers for win-7, so can I use my vista driver for win-7?

    Read the article

  • Is there a Windows or Linux equivalent of Soulver calculator application?

    - by Shevek
    I've just been shown a brilliant calculator app called Soulver which is only available on Mac OS X Maths on a Mac as it should be Soulver is a new kind of calculator application which uses a simple yet powerful word-processor style interface instead of the traditional "button" approach to doing math. Main Features No equals button - Soulver instantly calculates as you type. Multiple lines - Soulver lets you do math over multiple lines and edit previous expressions. Flexible to words - Soulver doesn't mind if you include words or labels between numbers. Basic functions - Soulver includes every standard calculator function, like sin(), cos() & tan() Clever English functions - Soulver includes some "English" math functions. For instance you can type "10% off $200" and get $180 Floating palettes - Soulver's answer & stats palettes will give you conversions and statistics on your work as your type Save your work - like a word processor, Soulver allows you to save and reopen your work This is a fantastic concept and I would really like to find it's equivalent for Windows and/or Linux. Any suggestions?

    Read the article

  • Dynamically loading Assemblies to reduce Runtime Depencies

    - by Rick Strahl
    I've been working on a request to the West Wind Application Configuration library to add JSON support. The config library is a very easy to use code-first approach to configuration: You create a class that holds the configuration data that inherits from a base configuration class, and then assign a persistence provider at runtime that determines where and how the configuration data is store. Currently the library supports .NET Configuration stores (web.config/app.config), XML files, SQL records and string storage.About once a week somebody asks me about JSON support and I've deflected this question for the longest time because frankly I think that JSON as a configuration store doesn't really buy a heck of a lot over XML. Both formats require the user to perform some fixup of the plain configuration data - in XML into XML tags, with JSON using JSON delimiters for properties and property formatting rules. Sure JSON is a little less verbose and maybe a little easier to read if you have hierarchical data, but overall the differences are pretty minor in my opinion. And yet - the requests keep rolling in.Hard Link Issues in a Component LibraryAnother reason I've been hesitant is that I really didn't want to pull in a dependency on an external JSON library - in this case JSON.NET - into the core library. If you're not using JSON.NET elsewhere I don't want a user to have to require a hard dependency on JSON.NET unless they want to use the JSON feature. JSON.NET is also sensitive to versions and doesn't play nice with multiple versions when hard linked. For example, when you have a reference to V4.4 in your project but the host application has a reference to version 4.5 you can run into assembly load problems. NuGet's Update-Package can solve some of this *if* you can recompile, but that's not ideal for a component that's supposed to be just plug and play. This is no criticism of JSON.NET - this really applies to any dependency that might change.  So hard linking the DLL can be problematic for a number reasons, but the primary reason is to not force loading of JSON.NET unless you actually need it when you use the JSON configuration features of the library.Enter Dynamic LoadingSo rather than adding an assembly reference to the project, I decided that it would be better to dynamically load the DLL at runtime and then use dynamic typing to access various classes. This allows me to run without a hard assembly reference and allows more flexibility with version number differences now and in the future.But there are also a couple of downsides:No assembly reference means only dynamic access - no compiler type checking or IntellisenseRequirement for the host application to have reference to JSON.NET or else get runtime errorsThe former is minor, but the latter can be problematic. Runtime errors are always painful, but in this case I'm willing to live with this. If you want to use JSON configuration settings JSON.NET needs to be loaded in the project. If this is a Web project, it'll likely be there already.So there are a few things that are needed to make this work:Dynamically create an instance and optionally attempt to load an Assembly (if not loaded)Load types into dynamic variablesUse Reflection for a few tasks like statics/enumsThe dynamic keyword in C# makes the formerly most difficult Reflection part - method calls and property assignments - fairly painless. But as cool as dynamic is it doesn't handle all aspects of Reflection. Specifically it doesn't deal with object activation, truly dynamic (string based) member activation or accessing of non instance members, so there's still a little bit of work left to do with Reflection.Dynamic Object InstantiationThe first step in getting the process rolling is to instantiate the type you need to work with. This might be a two step process - loading the instance from a string value, since we don't have a hard type reference and potentially having to load the assembly. Although the host project might have a reference to JSON.NET, that instance might have not been loaded yet since it hasn't been accessed yet. In ASP.NET this won't be a problem, since ASP.NET preloads all referenced assemblies on AppDomain startup, but in other executable project, assemblies are just in time loaded only when they are accessed.Instantiating a type is a two step process: Finding the type reference and then activating it. Here's the generic code out of my ReflectionUtils library I use for this:/// <summary> /// Creates an instance of a type based on a string. Assumes that the type's /// </summary> /// <param name="typeName">Common name of the type</param> /// <param name="args">Any constructor parameters</param> /// <returns></returns> public static object CreateInstanceFromString(string typeName, params object[] args) { object instance = null; Type type = null; try { type = GetTypeFromName(typeName); if (type == null) return null; instance = Activator.CreateInstance(type, args); } catch { return null; } return instance; } /// <summary> /// Helper routine that looks up a type name and tries to retrieve the /// full type reference in the actively executing assemblies. /// </summary> /// <param name="typeName"></param> /// <returns></returns> public static Type GetTypeFromName(string typeName) { Type type = null; // Let default name binding find it type = Type.GetType(typeName, false); if (type != null) return type; // look through assembly list var assemblies = AppDomain.CurrentDomain.GetAssemblies(); // try to find manually foreach (Assembly asm in assemblies) { type = asm.GetType(typeName, false); if (type != null) break; } return type; } To use this for loading JSON.NET I have a small factory function that instantiates JSON.NET and sets a bunch of configuration settings on the generated object. The startup code also looks for failure and tries loading up the assembly when it fails since that's the main reason the load would fail. Finally it also caches the loaded instance for reuse (according to James the JSON.NET instance is thread safe and quite a bit faster when cached). Here's what the factory function looks like in JsonSerializationUtils:/// <summary> /// Dynamically creates an instance of JSON.NET /// </summary> /// <param name="throwExceptions">If true throws exceptions otherwise returns null</param> /// <returns>Dynamic JsonSerializer instance</returns> public static dynamic CreateJsonNet(bool throwExceptions = true) { if (JsonNet != null) return JsonNet; lock (SyncLock) { if (JsonNet != null) return JsonNet; // Try to create instance dynamic json = ReflectionUtils.CreateInstanceFromString("Newtonsoft.Json.JsonSerializer"); if (json == null) { try { var ass = AppDomain.CurrentDomain.Load("Newtonsoft.Json"); json = ReflectionUtils.CreateInstanceFromString("Newtonsoft.Json.JsonSerializer"); } catch (Exception ex) { if (throwExceptions) throw; return null; } } if (json == null) return null; json.ReferenceLoopHandling = (dynamic) ReflectionUtils.GetStaticProperty("Newtonsoft.Json.ReferenceLoopHandling", "Ignore"); // Enums as strings in JSON dynamic enumConverter = ReflectionUtils.CreateInstanceFromString("Newtonsoft.Json.Converters.StringEnumConverter"); json.Converters.Add(enumConverter); JsonNet = json; } return JsonNet; }This code's purpose is to return a fully configured JsonSerializer instance. As you can see the code tries to create an instance and when it fails tries to load the assembly, and then re-tries loading.Once the instance is loaded some configuration occurs on it. Specifically I set the ReferenceLoopHandling option to not blow up immediately when circular references are encountered. There are a host of other small config setting that might be useful to set, but the default seem to be good enough in recent versions. Note that I'm setting ReferenceLoopHandling which requires an Enum value to be set. There's no real easy way (short of using the cardinal numeric value) to set a property or pass parameters from static values or enums. This means I still need to use Reflection to make this work. I'm using the same ReflectionUtils class I previously used to handle this for me. The function looks up the type and then uses Type.InvokeMember() to read the static property.Another feature I need is have Enum values serialized as strings rather than numeric values which is the default. To do this I can use the StringEnumConverter to convert enums to strings by adding it to the Converters collection.As you can see there's still a bit of Reflection to be done even in C# 4+ with dynamic, but with a few helpers this process is relatively painless.Doing the actual JSON ConversionFinally I need to actually do my JSON conversions. For the Utility class I need serialization that works for both strings and files so I created four methods that handle these tasks two each for serialization and deserialization for string and file.Here's what the File Serialization looks like:/// <summary> /// Serializes an object instance to a JSON file. /// </summary> /// <param name="value">the value to serialize</param> /// <param name="fileName">Full path to the file to write out with JSON.</param> /// <param name="throwExceptions">Determines whether exceptions are thrown or false is returned</param> /// <param name="formatJsonOutput">if true pretty-formats the JSON with line breaks</param> /// <returns>true or false</returns> public static bool SerializeToFile(object value, string fileName, bool throwExceptions = false, bool formatJsonOutput = false) { dynamic writer = null; FileStream fs = null; try { Type type = value.GetType(); var json = CreateJsonNet(throwExceptions); if (json == null) return false; fs = new FileStream(fileName, FileMode.Create); var sw = new StreamWriter(fs, Encoding.UTF8); writer = Activator.CreateInstance(JsonTextWriterType, sw); if (formatJsonOutput) writer.Formatting = (dynamic)Enum.Parse(FormattingType, "Indented"); writer.QuoteChar = '"'; json.Serialize(writer, value); } catch (Exception ex) { Debug.WriteLine("JsonSerializer Serialize error: " + ex.Message); if (throwExceptions) throw; return false; } finally { if (writer != null) writer.Close(); if (fs != null) fs.Close(); } return true; }You can see more of the dynamic invocation in this code. First I grab the dynamic JsonSerializer instance using the CreateJsonNet() method shown earlier which returns a dynamic. I then create a JsonTextWriter and configure a couple of enum settings on it, and then call Serialize() on the serializer instance with the JsonTextWriter that writes the output to disk. Although this code is dynamic it's still fairly short and readable.For full circle operation here's the DeserializeFromFile() version:/// <summary> /// Deserializes an object from file and returns a reference. /// </summary> /// <param name="fileName">name of the file to serialize to</param> /// <param name="objectType">The Type of the object. Use typeof(yourobject class)</param> /// <param name="binarySerialization">determines whether we use Xml or Binary serialization</param> /// <param name="throwExceptions">determines whether failure will throw rather than return null on failure</param> /// <returns>Instance of the deserialized object or null. Must be cast to your object type</returns> public static object DeserializeFromFile(string fileName, Type objectType, bool throwExceptions = false) { dynamic json = CreateJsonNet(throwExceptions); if (json == null) return null; object result = null; dynamic reader = null; FileStream fs = null; try { fs = new FileStream(fileName, FileMode.Open, FileAccess.Read); var sr = new StreamReader(fs, Encoding.UTF8); reader = Activator.CreateInstance(JsonTextReaderType, sr); result = json.Deserialize(reader, objectType); reader.Close(); } catch (Exception ex) { Debug.WriteLine("JsonNetSerialization Deserialization Error: " + ex.Message); if (throwExceptions) throw; return null; } finally { if (reader != null) reader.Close(); if (fs != null) fs.Close(); } return result; }This code is a little more compact since there are no prettifying options to set. Here JsonTextReader is created dynamically and it receives the output from the Deserialize() operation on the serializer.You can take a look at the full JsonSerializationUtils.cs file on GitHub to see the rest of the operations, but the string operations are very similar - the code is fairly repetitive.These generic serialization utilities isolate the dynamic serialization logic that has to deal with the dynamic nature of JSON.NET, and any code that uses these functions is none the wiser that JSON.NET is dynamically loaded.Using the JsonSerializationUtils WrapperThe final consumer of the SerializationUtils wrapper is an actual ConfigurationProvider, that is responsible for handling reading and writing JSON values to and from files. The provider is simple a small wrapper around the SerializationUtils component and there's very little code to make this work now:The whole provider looks like this:/// <summary> /// Reads and Writes configuration settings in .NET config files and /// sections. Allows reading and writing to default or external files /// and specification of the configuration section that settings are /// applied to. /// </summary> public class JsonFileConfigurationProvider<TAppConfiguration> : ConfigurationProviderBase<TAppConfiguration> where TAppConfiguration: AppConfiguration, new() { /// <summary> /// Optional - the Configuration file where configuration settings are /// stored in. If not specified uses the default Configuration Manager /// and its default store. /// </summary> public string JsonConfigurationFile { get { return _JsonConfigurationFile; } set { _JsonConfigurationFile = value; } } private string _JsonConfigurationFile = string.Empty; public override bool Read(AppConfiguration config) { var newConfig = JsonSerializationUtils.DeserializeFromFile(JsonConfigurationFile, typeof(TAppConfiguration)) as TAppConfiguration; if (newConfig == null) { if(Write(config)) return true; return false; } DecryptFields(newConfig); DataUtils.CopyObjectData(newConfig, config, "Provider,ErrorMessage"); return true; } /// <summary> /// Return /// </summary> /// <typeparam name="TAppConfig"></typeparam> /// <returns></returns> public override TAppConfig Read<TAppConfig>() { var result = JsonSerializationUtils.DeserializeFromFile(JsonConfigurationFile, typeof(TAppConfig)) as TAppConfig; if (result != null) DecryptFields(result); return result; } /// <summary> /// Write configuration to XmlConfigurationFile location /// </summary> /// <param name="config"></param> /// <returns></returns> public override bool Write(AppConfiguration config) { EncryptFields(config); bool result = JsonSerializationUtils.SerializeToFile(config, JsonConfigurationFile,false,true); // Have to decrypt again to make sure the properties are readable afterwards DecryptFields(config); return result; } }This incidentally demonstrates how easy it is to create a new provider for the West Wind Application Configuration component. Simply implementing 3 methods will do in most cases.Note this code doesn't have any dynamic dependencies - all that's abstracted away in the JsonSerializationUtils(). From here on, serializing JSON is just a matter of calling the static methods on the SerializationUtils class.Already, there are several other places in some other tools where I use JSON serialization this is coming in very handy. With a couple of lines of code I was able to add JSON.NET support to an older AJAX library that I use replacing quite a bit of code that was previously in use. And for any other manual JSON operations (in a couple of apps I use JSON Serialization for 'blob' like document storage) this is also going to be handy.Performance?Some of you might be thinking that using dynamic and Reflection can't be good for performance. And you'd be right… In performing some informal testing it looks like the performance of the native code is nearly twice as fast as the dynamic code. Most of the slowness is attributable to type lookups. To test I created a native class that uses an actual reference to JSON.NET and performance was consistently around 85-90% faster with the referenced code. That being said though - I serialized 10,000 objects in 80ms vs. 45ms so this isn't hardly slouchy. For the configuration component speed is not that important because both read and write operations typically happen once on first access and then every once in a while. But for other operations - say a serializer trying to handle AJAX requests on a Web Server one would be well served to create a hard dependency.Dynamic Loading - Worth it?On occasion dynamic loading makes sense. But there's a price to be paid in added code complexity and a performance hit. But for some operations that are not pivotal to a component or application and only used under certain circumstances dynamic loading can be beneficial to avoid having to ship extra files and loading down distributions. These days when you create new projects in Visual Studio with 30 assemblies before you even add your own code, trying to keep file counts under control seems a good idea. It's not the kind of thing you do on a regular basis, but when needed it can be a useful tool. Hopefully some of you find this information useful…© Rick Strahl, West Wind Technologies, 2005-2013Posted in .NET  C#   Tweet !function(d,s,id){var js,fjs=d.getElementsByTagName(s)[0];if(!d.getElementById(id)){js=d.createElement(s);js.id=id;js.src="//platform.twitter.com/widgets.js";fjs.parentNode.insertBefore(js,fjs);}}(document,"script","twitter-wjs"); (function() { var po = document.createElement('script'); po.type = 'text/javascript'; po.async = true; po.src = 'https://apis.google.com/js/plusone.js'; var s = document.getElementsByTagName('script')[0]; s.parentNode.insertBefore(po, s); })();

    Read the article

< Previous Page | 846 847 848 849 850 851 852 853 854 855 856 857  | Next Page >