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  • failed to load viewstate. the control tree into which viewstate

    - by Mohan
    Hi Everybody, i have a gridview control . When I change page of gridview control i get this error. Server Error in '/' Application. Failed to load viewstate. The control tree into which viewstate is being loaded must match the control tree that was used to save viewstate during the previous request. For example, when adding controls dynamically, the controls added during a post-back must match the type and position of the controls added during the initial request. how to tackle with this problem. It's urgent Any suggestion? Thanks in advance.

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  • How to fix weird scrolling/alignment behavior when using keyboard in MenuStrip?

    - by bentsai
    I started noticing strange behavior when navigating the main toolbar of my Winforms application, and I don't know how to fix it. When I initially open the dropdown of the File menu, it looks like this: I begin to scroll down each item with the arrow keys, and everything is fine until I reach "Exit". As soon as I hit the down arrow key from "Log Off", or if I hit the up arrow key from "Open", the menu rearranges itself to look like this: I'm puzzled by this behavior. The menu still works, and from this point, if I start scrolling up, I can get the arrangement back to normal: A few observations: The menu still works. This doesn't happen when using the mouse. I have some code that toggles the Visible property of some of the menu items. I was able to modify what the arrangement was by playing around with this, but it was still messed up. Can anyone help me understand what is going on, and how to fix it?

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  • Create unordered list tree menu from data stored in an table with the adjacency list model...php

    - by Ronedog
    I need to create a tree menu of "nth" subcategories. I settled on using the adjacency list model for my table structure, because I won't be updating this table very much and this seemed the easiest to implement for my use. I want to style the output using "ul" and "li" tags...I already have a css and jquery solution to do the styling. My problem comes from pulling the data out of the database and using a recursive function via PHP to build the list ... the list is a concatenated string that gets parsed to build the tree. I'm really having a hard time getting the closing "ul" and "li" tags to line up just where they need to be. Is this the best way to do this? Are there other better ways using arrays or something like that to do this? Any examples you can point me to of "best practices" for building a list like this will be appreciated. Thanks.

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  • Strange behavior with Powershell scriptblock variable scope and modules, any suggestions?

    - by DanMan
    NOTE: I'm using PowerShell 2.0 on Windows Vista. I'm trying to add support for specifying build arguments to psake, but I've run into some strange PowerShell variable scoping behavior dealing specifically with calling functions that have been exported using Export-ModuleMember (which is how psake exposes it's main method). Following is a simple PowerShell module to illustrate (named repoCase.psm1): function Test { param( [Parameter(Position=0,Mandatory=0)] [scriptblock]$properties = {} ) $defaults = {$message = "Hello, world!"} Write-Host "Before running defaults, message is: $message" . $defaults #At this point, $message is correctly set to "Hellow, world!" Write-Host "Aftering running defaults, message is: $message" . $properties #At this point, I would expect $message to be set to whatever is passed in, #which in this case is "Hello from poperties!", but it isn't. Write-Host "Aftering running properties, message is: $message" } Export-ModuleMember -Function "Test" To test the module, run the following sequence of commands (be sure you're in the same directory as the repoCase.psm1): Import-Module .\repoCase.psm1 #Note that $message should be null Write-Host "Before execution - In global scope, message is: $message" Test -properties { "Executing properties, message is $message"; $message = "Hello from properties!"; } #Now $message is set to the value from the script block. The script block affected only the global scope. Write-Host "After execution - In global scope, message is: $message" Remove-Module repoCase The behavior I expected was for the script block I passed to Test to affect the local scope of Test. It is being 'dotsourced' in, so any changes it makes should be within the scope of the caller. However, that's not what's happening, it seems to be affecting the scope of where it was declared. Here's the output: Before execution - In global scope, message is: Before running defaults, message is: Aftering running defaults, message is: Hello, world! Executing properties, message is Aftering running properties, message is: Hello, world! After execution - In global scope, message is: Hello from properties! Interestingly, if I don't export Test as a module and instead just declare the function and invoke it, everything works just like I would expect it to. The script block affects only Test's scope, and does not modify the global scope. I'm not a PowerShell guru, but can someone explain this behavior to me?

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  • How can I traverse the EMF object tree generated by Xtext?

    - by reprogrammer
    I'm using Xtext to define my DSL. Xtext generates a parser that lets me traverse the EMF model of my input DSL. I'd like to translate this EMF model into some other tree. To do this translation, I need to traverse the tree. But, I couldn't find a visitor class for the EMF model generated by Xtext. The closest thing that I've found is a Switch class that visits a single node. I can traverse the EMF model myself and invoke the Switch class on each node that I visit. But, I wonder if there exists a visitor functionality in Xtext that implements the model traversal.

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  • How can I define pre/post-increment behavior in Perl objects?

    - by Zaid
    Date::Simple objects display this behavior. In the case of Date::Simple objects, $date++ returns the next day's date. Date::Simple objects are immutable. After assigning $date1 to $date2, no change to $date1 can affect $date2. This means, for example, that there is nothing like a set_year operation, and $date++ assigns a new object to $date. How can one custom define the pre/post-incremental behavior of an object, such that ++$object or $object-- performs a particular action? I've skimmed over perlboot, perltoot, perltooc and perlbot, but I don't see any examples showing how this can be done.

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  • How can I debug or set a break statement inside an expression tree?

    - by Abel
    When an external library contains a LINQ provider, and it throws an exception when executing a dynamic expression tree, how can I break when that expression is thrown? For example, I use a third party LINQ2CRM provider, which allows me to call the Max<TSource, TResult>() method of IQueryable, but when it throws an InvalidCastException, I fail to break on the spot when the exception is thrown, making it hard to review the stack-trace because it's already unwinded when the debugger breaks it in my code. I've set "break on throw" for the mentioned exception. My debug settings are: Clarification on where exactly I'd want to break. I do not want to break in side the LINQ Expression, but instead, I want to break when the expression tree is executed, or, put in other words, when the IQueryable extension method Max() calls the override provided by the LINQ provider. The top of the stacktrace looks like this, which is where I would like to break inside (or step through, or whatever): at XrmLinq.QueryProviderBase.Execute[T](Expression expression) at System.Linq.Queryable.Max[TSource,TResult](IQueryable`1 source, Expression`1 selector)

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  • Build a decision tree for classification of large amount data,using python?

    - by kaushik
    Hi,i am working for speech synthesis.In this i have a large number of pronunciation for each phone i.e alphabet and need to classify them according to few feature such as segment size(int) and alphabet itself(string) into a smaller set suitable for that particular context. For this purpose,i have decided to use decision tree for classification.the data to be parsed is in the S expression format.eg:((question)(LEFTNODE)(RIGHTNODE)). i hav idea for building decision tree for normal buit in type such as list..looking for suggestion for implementation for S expression.. kindly help.. Thanks in advance.. Note:this question may look similar to my prev post,srry if cant giv multiple post.already edited it many times so though of wirting new question instead of editing again

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  • Chess board position numbers in 6-rooted-binary tree?

    - by HH
    The maximum number of adjacent vertices is 6 that corresponds to the number of roots. By the term root, I mean the number of children for each node. If adjacent square is empty, fill it with Z-node. So every square will have 6 nodes. How can you formulate it with binary tree? Is the structure just 6-rooted-binary tree? What is the structure called if nodes change their positions? Suppose partially ordered list where its units store a large randomly expanding board. I want a self-adjusting data structure, where it is easy to calculate distances between nodes. What is its name?

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  • Can I ReRender the entire tree of a component?

    - by Ben
    Hi, I have a JSF application with several major components and a component tree under each. On a certain event (Value change) I would like to reRender the entire component tree for one of those components. For example: can I rerender components 1,2 and 3 in one shot here: <h:panelgroup id="1"> <h:panelgroup id="2"> <h:panelgroup id="3"> <h:panelgroup/> <h:panelgroup/> <h:panelgroup/> <h:commandButton rerender="1*"> <--- Made up code. Is that possible? Another Idea - Can I reRender with wildcards? (I.E - ReRender all components who's ID's begin or contain: "UpdateMe") Thanks!

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  • How do I manipulate a tree of immutable objects?

    - by Frederik
    I'm building an entire application out of immutable objects so that multi-threading and undo become easier to implement. I'm using the Google Collections Library which provides immutable versions of Map, List, and Set. My application model looks like a tree: Scene is a top-level object that contains a reference to a root Node. Each Node can contain child Nodes and Ports. An object graph might look like this: Scene | +-- Node | +-- Node | +- Port +-- Node | +- Port +- Port If all of these objects are immutable, controlled by a top-level SceneController object: What is the best way to construct this hierarchy? How would I replace an object that is arbitrarily deep in the object tree? Is there a way to support back-links, e.g. a Node having a "parent" attribute?

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  • Is Memory increase create difference in output or behavior of java application?

    - by Nitz
    Hey Guys I have created one java-swing application. The application runs perfectly runs perfect on my pc. But it doesn't run perfectly on client pc. I had increase my Virtual Memory, earlier on my pc. So my question is.. Is changing memory limit, effect or change application behavior? Is there anything that change the behavior of java application? bcz same application runs perfectly on my pc and same application does not running perfectly on client pc? and there is no problem in code, i have checked three times.

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  • Emulate "Go to Dekstop/Home/etc." behavior in OS X via AppleScript

    - by pattulus
    OS X has build in support for going to certain Folders (Home, Utilities, Desktop, etc.) via a Shortcut. I wanted to emulate this behavior for the the Downloads Folder. The only thing that is missing the script below is that it won’t succeed when no window is opened in the Finder (see Error message). tell application "Finder" activate set target of Finder window 1 to folder "Downloads" of folder "username" of disk "Macintosh HD" end tell Error message: error "Finder got an error: Can’t set Finder window 1 to folder \"Downloads\" of folder \"username\" of disk \"Macintosh HD\"." number -10006 from Finder window 1 It great if you know about some kind of 'if-compliement' that triggers opening the Downloads Folder in case there is no window 1 open in the Finder. Thanks in advance.

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  • How can I make a vpn network login the default behavior for logging into Windows?

    - by Danny
    To login to the machine, I have to login to our domain. When I am at work, the unauthenticated wireless permits access to the domain. However, the internet is not available until I connect via the vpn. From home, I have to connect via the vpn first, then I can login to the domain. I have successfully setup a network logon with the vpn (following the directions found here). And for the most part it works correctly. (There is an issue with logout/login I haven't figured out just yet). As I currently have to Switch User and select the Network Login button, I'd like to know if it is possible to have the network login the default behavior when logging into the system. This is mostly a usability issue than anything else.

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  • Is Family Tree Maker 2011 the right upgrade for a FTM 11 user?

    - by bill weaver
    My father has used Family Tree Maker for years, but hasn't upgraded since version 11. It is difficult to tell from reviews at Amazon and other places whether upgrading to FTM 2011 is a good choice. File incompatibilities and upgrade woes sound like customer service is lacking, and i've read reports of it uploading your data to their database but then trying to sell you a download of data. Looking at the ancestry.com site makes me think it's solely about selling add-ons and upgrades. On the other hand, the feature set seems fairly rich and the software has a pretty strong following. I was able to get Gramps working on my system, but that's not going to work for my dad. Any advice on a good upgrade path?

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  • Debian/Ubuntu: Enabling "dist-upgrade" behavior for unattended-upgrades?

    - by Mark Renouf
    We've got a customized distribution of Ubuntu, a repository with some custom packages and we run unattended-upgrades on a number of systems. What we want to be able to do is supply an update of one of our packages which might have a new dependency which is not yet installed. I understand apt normally prevents that from happening automatically, and using dist-upgrade would permit it. How can I get that behavior so our unattended upgrades work the same way? Ideally we'd only want new packages installed if one of our packages causes it to be needed (either as a direct dependency or a child, etc.) Should I be aware of any potential problems or increased risk of breakage. The systems are generally not easily accessed via the console so anything causing a problem requiring manual intervention would be very bad!

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  • Copying a large directory tree locally? cp or rsync?

    - by Rory
    I have to copy a large directory tree, about 1.8 TB. It's all local. Out of habit I'd use rsync, however I wonder if there's much point, and if I should rather use cp. I'm worried about permissions and uid/gid, since they have to be preserved in the clopy (I know rsync does this). As well as thinks like symlinks. The destination is empty, so I don't have to worry about conditionally updating some files. It's all local disk access, so I don't have to worry about ssh or network. The reason I'd be tempted away from rsync, is because rsync might do more than I need. rsync checksums files. I don't need that, and am concerned that it might take longer than cp. So what do you reckon, rsync or cp?

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  • Gnome+NX clipboard behavior; auto-copy on select?

    - by threecheeseopera
    I am having issues with the Gnome(/Linux/Debian+Ubuntu) clipboard when connected remotely; it's default behavior appears to be to automatically add text to a clipboard buffer when that text is selected. This is not usually a problem, until I need to log into one of these systems remotely (w/ GUI), and attempt to use a shared clipboard. If I 'copy' text on the local machine (destined to replace some text on the remote machine), that copy buffer is overwritten as soon as I select the text on the remote machine to be replaced. Is there some way around this? It sort of drives me nuts. Thanks! UPDATE: This is really an NX server issue; X11 supports multiple clipboards ("selections": clipboard, primary. secondary; see this excellent article) that behave differently, and it appears that my problem is related to how NX server translates this over to the host machine.

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  • Windows 7 Explorer - Activate mouse focus to be able to scroll in tree and file view?

    - by none
    I'd like to be able to scroll in the tree view without having to click in it. Is there a way to do this? I have once used a tool that generally gives focus to the window underneath the mouse cursor, but this caused some other glitches so I would like to achieve this without an extra tool. I also think that there are programs that embed the Windows Explorer and offer more features, including the behaviour I would like to have. But maybe a registry value change is all that is needed?

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  • Where's my tab completion and up-arrow behavior? (Ubuntu 10.04)

    - by pastorius
    I'm new to Linux, trying Ubuntu 10.04, preconfigured by host. When I log in (SSH) using the preconfigured account, the shell prompt is: user@hostname:~$ The up arrow scrolls through the list of recent shell commands, and tab-completion works as expected. However, when I create an account and log in (SSH) using that account, the shell prompt is simply "$", and the up arrow just prints a control character (^[[A). Can anyone tell me how to get my prompt, tab-completion, and up-arrow behavior set up? The fact that I'm getting control characters when I up-arrow makes me think that my account (or session) is in some mode I'm unfamiliar with. I know there is tab-completion code stored in bashrc that I can uncomment, but that doesn't seem to have any effect, even after logging out and logging back in. Am I in some strange mode when I SSH in with the new account, or are there just some session/account settings I need to set up, and can find information for anywhere on the Internet if I just knew what to look for?

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  • Let’s Get Social

    - by Kristin Rose
    v\:* {behavior:url(#default#VML);} o\:* {behavior:url(#default#VML);} w\:* {behavior:url(#default#VML);} .shape {behavior:url(#default#VML);} Normal 0 false false false false EN-US X-NONE X-NONE /* Style Definitions */ table.MsoNormalTable {mso-style-name:"Table Normal"; mso-tstyle-rowband-size:0; mso-tstyle-colband-size:0; mso-style-noshow:yes; mso-style-priority:99; mso-style-qformat:yes; mso-style-parent:""; mso-padding-alt:0in 5.4pt 0in 5.4pt; mso-para-margin-top:0in; mso-para-margin-right:0in; mso-para-margin-bottom:10.0pt; mso-para-margin-left:0in; line-height:115%; mso-pagination:widow-orphan; font-size:11.0pt; font-family:"Calibri","sans-serif"; mso-ascii-font-family:Calibri; mso-ascii-theme-font:minor-latin; mso-fareast-font-family:"Times New Roman"; mso-fareast-theme-font:minor-fareast; mso-hansi-font-family:Calibri; mso-hansi-theme-font:minor-latin; mso-bidi-font-family:"Times New Roman"; mso-bidi-theme-font:minor-bidi;} You can try to run from it like a bad Facebook picture but you can’t hide. Social media as we know it is quickly taking over our lives and is not going away any time soon. Though attempting to reach as many Twitter followers as Lady Gaga is daunting, learning how to leverage social media to meet your customer’s needs is not. For Oracle, this means interacting directly with our partners through our many social media outlets, and refraining from posting a mindless status on the pastrami on rye we ate for lunch today… though it was delicious. The “correct” way to go about social media is going to mean something different to each company. For example, sending a customer more than one friend request a day may not be the best way to get their attention, but using social media as a two-way marketing channel is. Oracle’s Partner Business Center’s (PBC) twitter handle was recently mentioned by Elateral as the “ideal way to engage with your market and use social media in the channel”. Why you ask? Because the PBC has two named social media leads manning the Twitter feed at all times, helping partners get the information and answers they need more quickly than a Justin Bieber video gone viral. So whether you want to post a video of your favorite customer attempting the Marshmallow challenge or tweet like there’s no tomorrow, be sure to follow @OraclePartnerBiz today, and see how they can help you achieve your next partner milestone with Oracle. Happy Socializing, The OPN Communications Team v\:* {behavior:url(#default#VML);} o\:* {behavior:url(#default#VML);} w\:* {behavior:url(#default#VML);} .shape {behavior:url(#default#VML);} Normal 0 false false false false EN-US X-NONE X-NONE /* Style Definitions */ table.MsoNormalTable {mso-style-name:"Table Normal"; mso-tstyle-rowband-size:0; mso-tstyle-colband-size:0; mso-style-noshow:yes; mso-style-priority:99; mso-style-qformat:yes; mso-style-parent:""; mso-padding-alt:0in 5.4pt 0in 5.4pt; mso-para-margin-top:0in; mso-para-margin-right:0in; mso-para-margin-bottom:10.0pt; mso-para-margin-left:0in; line-height:115%; mso-pagination:widow-orphan; font-size:11.0pt; font-family:"Calibri","sans-serif"; mso-ascii-font-family:Calibri; mso-ascii-theme-font:minor-latin; mso-fareast-font-family:"Times New Roman"; mso-fareast-theme-font:minor-fareast; mso-hansi-font-family:Calibri; mso-hansi-theme-font:minor-latin; mso-bidi-font-family:"Times New Roman"; mso-bidi-theme-font:minor-bidi;} v\:* {behavior:url(#default#VML);} o\:* {behavior:url(#default#VML);} w\:* {behavior:url(#default#VML);} .shape {behavior:url(#default#VML);} Normal 0 false false false false EN-US X-NONE X-NONE /* Style Definitions */ table.MsoNormalTable {mso-style-name:"Table Normal"; mso-tstyle-rowband-size:0; mso-tstyle-colband-size:0; mso-style-noshow:yes; mso-style-priority:99; mso-style-qformat:yes; mso-style-parent:""; mso-padding-alt:0in 5.4pt 0in 5.4pt; mso-para-margin-top:0in; mso-para-margin-right:0in; mso-para-margin-bottom:10.0pt; mso-para-margin-left:0in; line-height:115%; mso-pagination:widow-orphan; font-size:11.0pt; font-family:"Calibri","sans-serif"; mso-ascii-font-family:Calibri; mso-ascii-theme-font:minor-latin; mso-fareast-font-family:"Times New Roman"; mso-fareast-theme-font:minor-fareast; mso-hansi-font-family:Calibri; mso-hansi-theme-font:minor-latin; mso-bidi-font-family:"Times New Roman"; mso-bidi-theme-font:minor-bidi;}

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  • How can I automatically synchronize a directory tree on multiple machines?

    - by Blacklight Shining
    I have two Mac laptops and a Debian server, each with a directory that I would like to keep in sync between the three. The solution should meet the following criteria (in rough order of importance): It must not use any third-party service (e.g. Dropbox, SugarSync, Google whatever). This does not include installing additional software (as long as it's free). It must not require me to use specific directories or change my way of storing things. (Dropbox does this IIRC) It must work in all directions (changes made on /any/ machine should be pushed to the others) All data sent must be encrypted (I have ssh keypairs set up already) It must work even when not all machines are available (changes should be pushed to a machine when it comes back online) It must work even when the /directories/ on some machines are not available (they may be stored on disk images which will not always be mounted) This can be solved for Macs by using launchd to automatically launch and kill (or in some way change the behavior of) whatever daemon is used for syncing when the images are mounted and unmounted. It must be immediate (using an event-based system, not a periodic one like cron) It must be flexible (if more machines are added, I should be able to incorporate them easily) I also have some preferences that I would like to be fulfilled, but do not have to be: It should notify me somehow if there are conflicts or other errors. It should recognize symbolic and hard links and create corresponding ones. It should allow me to create a list of exceptions (subdirectories which will not be synced at all). It should not require me to set up port forwarding or otherwise reconfigure a network. This can be solved by using an ssh tunnel with reverse port forwarding. If you have a solution that meets some, but not all of the criteria, please contribute it in the comments as it might be useful in some way, and it might be possible to meet some of the criteria separately. What I tried, and why it didn't work: rsync and lsyncd do not support bidirectional synchronization csync2 is designed for server clusters and does not appear to work with machines with dynamic IPs DRBD (suggested by amotzg) involves installing a kernel module and does not appear to work on systems running OS X

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  • ASP.NET MVC Postbacks and HtmlHelper Controls ignoring Model Changes

    - by Rick Strahl
    So here's a binding behavior in ASP.NET MVC that I didn't really get until today: HtmlHelpers controls (like .TextBoxFor() etc.) don't bind to model values on Postback, but rather get their value directly out of the POST buffer from ModelState. Effectively it looks like you can't change the display value of a control via model value updates on a Postback operation. To demonstrate here's an example. I have a small section in a document where I display an editable email address: This is what the form displays on a GET operation and as expected I get the email value displayed in both the textbox and plain value display below, which reflects the value in the mode. I added a plain text value to demonstrate the model value compared to what's rendered in the textbox. The relevant markup is the email address which needs to be manipulated via the model in the Controller code. Here's the Razor markup: <div class="fieldcontainer"> <label> Email: &nbsp; <small>(username and <a href="http://gravatar.com">Gravatar</a> image)</small> </label> <div> @Html.TextBoxFor( mod=> mod.User.Email, new {type="email",@class="inputfield"}) @Model.User.Email </div> </div>   So, I have this form and the user can change their email address. On postback the Post controller code then asks the business layer whether the change is allowed. If it's not I want to reset the email address back to the old value which exists in the database and was previously store. The obvious thing to do would be to modify the model. Here's the Controller logic block that deals with that:// did user change email? if (!string.IsNullOrEmpty(oldEmail) && user.Email != oldEmail) { if (userBus.DoesEmailExist(user.Email)) { userBus.ValidationErrors.Add("New email address exists already. Please…"); user.Email = oldEmail; } else // allow email change but require verification by forcing a login user.IsVerified = false; }… model.user = user; return View(model); The logic is straight forward - if the new email address is not valid because it already exists I don't want to display the new email address the user entered, but rather the old one. To do this I change the value on the model which effectively does this:model.user.Email = oldEmail; return View(model); So when I press the Save button after entering in my new email address ([email protected]) here's what comes back in the rendered view: Notice that the textbox value and the raw displayed model value are different. The TextBox displays the POST value, the raw value displays the actual model value which are different. This means that MVC renders the textbox value from the POST data rather than from the view data when an Http POST is active. Now I don't know about you but this is not the behavior I expected - initially. This behavior effectively means that I cannot modify the contents of the textbox from the Controller code if using HtmlHelpers for binding. Updating the model for display purposes in a POST has in effect - no effect. (Apr. 25, 2012 - edited the post heavily based on comments and more experimentation) What should the behavior be? After getting quite a few comments on this post I quickly realized that the behavior I described above is actually the behavior you'd want in 99% of the binding scenarios. You do want to get the POST values back into your input controls at all times, so that the data displayed on a form for the user matches what they typed. So if an error occurs, the error doesn't mysteriously disappear getting replaced either with a default value or some value that you changed on the model on your own. Makes sense. Still it is a little non-obvious because the way you create the UI elements with MVC, it certainly looks like your are binding to the model value:@Html.TextBoxFor( mod=> mod.User.Email, new {type="email",@class="inputfield",required="required" }) and so unless one understands a little bit about how the model binder works this is easy to trip up. At least it was for me. Even though I'm telling the control which model value to bind to, that model value is only used initially on GET operations. After that ModelState/POST values provide the display value. Workarounds The default behavior should be fine for 99% of binding scenarios. But if you do need fix up values based on your model rather than the default POST values, there are a number of ways that you can work around this. Initially when I ran into this, I couldn't figure out how to set the value using code and so the simplest solution to me was simply to not use the MVC Html Helper for the specific control and explicitly bind the model via HTML markup and @Razor expression: <input type="text" name="User.Email" id="User_Email" value="@Model.User.Email" /> And this produces the right result. This is easy enough to create, but feels a little out of place when using the @Html helpers for everything else. As you can see by the difference in the name and id values, you also are forced to remember the naming conventions that MVC imposes in order for ModelBinding to work properly which is a pain to remember and set manually (name is the same as the property with . syntax, id replaces dots with underlines). Use the ModelState Some of my original confusion came because I didn't understand how the model binder works. The model binder basically maintains ModelState on a postback, which holds a value and binding errors for each of the Post back value submitted on the page that can be mapped to the model. In other words there's one ModelState entry for each bound property of the model. Each ModelState entry contains a value property that holds AttemptedValue and RawValue properties. The AttemptedValue is essentially the POST value retrieved from the form. The RawValue is the value that the model holds. When MVC binds controls like @Html.TextBoxFor() or @Html.TextBox(), it always binds values on a GET operation. On a POST operation however, it'll always used the AttemptedValue to display the control. MVC binds using the ModelState on a POST operation, not the model's value. So, if you want the behavior that I was expecting originally you can actually get it by clearing the ModelState in the controller code:ModelState.Clear(); This clears out all the captured ModelState values, and effectively binds to the model. Note this will produce very similar results - in fact if there are no binding errors you see exactly the same behavior as if binding from ModelState, because the model has been updated from the ModelState already and binding to the updated values most likely produces the same values you would get with POST back values. The big difference though is that any values that couldn't bind - like say putting a string into a numeric field - will now not display back the value the user typed, but the default field value or whatever you changed the model value to. This is the behavior I was actually expecting previously. But - clearing out all values might be a bit heavy handed. You might want to fix up one or two values in a model but rarely would you want the entire model to update from the model. So, you can also clear out individual values on an as needed basis:if (userBus.DoesEmailExist(user.Email)) { userBus.ValidationErrors.Add("New email address exists already. Please…"); user.Email = oldEmail; ModelState.Remove("User.Email"); } This allows you to remove a single value from the ModelState and effectively allows you to replace that value for display from the model. Why? While researching this I came across a post from Microsoft's Brad Wilson who describes the default binding behavior best in a forum post: The reason we use the posted value for editors rather than the model value is that the model may not be able to contain the value that the user typed. Imagine in your "int" editor the user had typed "dog". You want to display an error message which says "dog is not valid", and leave "dog" in the editor field. However, your model is an int: there's no way it can store "dog". So we keep the old value. If you don't want the old values in the editor, clear out the Model State. That's where the old value is stored and pulled from the HTML helpers. There you have it. It's not the most intuitive behavior, but in hindsight this behavior does make some sense even if at first glance it looks like you should be able to update values from the model. The solution of clearing ModelState works and is a reasonable one but you have to know about some of the innards of ModelState and how it actually works to figure that out.© Rick Strahl, West Wind Technologies, 2005-2012Posted in ASP.NET  MVC   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); })();

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