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• Java: how to tell if a line in a text file was supposed to be blank?

  - by defn

  I'm working on a project in which I have to read in a Grammar file (breaking it up into my data structure), with the goal of being able to generate a random "DearJohnLetter". My problem is that when reading in the .txt file, I don't know how find out whether the file was supposed to be a completely blank line or not, which is detrimental to the program. Here is an example of part of the file, How do i tell if the next line was supposed to be a blank line? (btw I'm just using a buffered reader) Thanks! <start> I have to break up with you because <reason> . But let's still <disclaimer> . <reason> <dubious-excuse> <dubious-excuse> , and also because <reason> <dubious-excuse> my <person> doesn't like you I'm in love with <another> I haven't told you this before but <harsh> I didn't have the heart to tell you this when we were going out, but <harsh> you never <romantic-with-me> with me any more you don't <romantic> any more my <someone> said you were bad news

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• Recognizing terminals in a CFG production previously not defined as tokens.

  - by kmels

  I'm making a generator of LL(1) parsers, my input is a CoCo/R language specification. I've already got a Scanner generator for that input. Suppose I've got the following specification: COMPILER 1. CHARACTERS digit="0123456789". TOKENS number = digit{digit}. decnumber = digit{digit}"."digit{digit}. PRODUCTIONS Expression = Term{"+"Term|"-"Term}. Term = Factor{"*"Factor|"/"Factor}. Factor = ["-"](Number|"("Expression")"). Number = (number|decnumber). END 1. So, if the parser generated by this grammar receives a word "1+1", it'd be accepted i.e. a parse tree would be found. My question is, the character "+" was never defined in a token, but it appears in the non-terminal "Expression". How should my generated Scanner recognize it? It would not recognize it as a token. Is this a valid input then? Should I add this terminal in TOKENS and then consider an error routine for a Scanner for it to skip it? How does usual language specifications handle this?

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• Why does CGPDFPageGetDrawingTransform() crash with SIGABRT when specifying a rotation?

  - by David

  When I call CGPDFPageGetDrawingTransform() with a rotation argument, the application crashes. If I specify no rotation, there is no crash. Here is my drawLayer:inContext: method: - (void)drawLayer:(CALayer*)layer inContext:(CGContextRef)context { CGContextSetRGBFillColor(context, 1.0, 1.0, 1.0, 1.0); CGRect boundingBox = CGContextGetClipBoundingBox(context); CGContextFillRect(context, boundingBox); //convert to UIKit native coodinate system CGContextTranslateCTM(context, 0.0, self.bounds.size.height); CGContextScaleCTM(context, 1.0, -1.0); //Rotate the pdf_page CGAffineTransform pfd_transform = CGPDFPageGetDrawingTransform(self.page, kCGPDFCropBox, self.frame, 58.46f, true); CGContextSaveGState (context); CGContextConcatCTM (context, pfd_transform); CGContextClipToRect (context, self.frame); CGContextDrawPDFPage (context, self.page); CGContextRestoreGState (context); } In the long run, I would like to rotate the pdf dynamically to follow a users heading. Maybe I am going at this all wrong... Thank you for your time.

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• Webapp: safetly update a shared List/Map in the AppContext

  - by al nik

  I've Lists and Maps in my WebAppContext. Most of the time these are only read by multiple Threads but sometimes there's the need to update or add some data. I'm wondering what's the best way to do this without incurring in a ConcurrentModificationException. I think that using CopyOnWriteArrayList I can achieve what I want in terms of - I do not have to sync on every read operation- I can safety update the list while other threads are reading it. Is this the best solution? What about Maps?

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• Theory of computation - Using the pumping lemma for CFLs

  - by Tony

  I'm reviewing my notes for my course on theory of computation and I'm having trouble understanding how to complete a certain proof. Here is the question: A = {0^n 1^m 0^n | n>=1, m>=1} Prove that A is not regular. It's pretty obvious that the pumping lemma has to be used for this. So, we have |vy| = 1 |vxy| <= p (p being the pumping length, = 1) uv^ixy^iz exists in A for all i = 0 Trying to think of the correct string to choose seems a bit iffy for this. I was thinking 0^p 1^q 0^p, but I don't know if I can obscurely make a q, and since there is no bound on u, this could make things unruly.. So, how would one go about this?

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• remove schema from linq datacontexts

  - by Jeremy

  When I add stored procedures to a linq datacontext, by default visual studio prefixes the stored procedure with the sql schema that it is in. Is there any way to stop this? In our environment, the stored procedures may be moved to other schemas over time, and we will default the schema based on the sql user used to connect. Do I have to do this manually or can I somehow turn off the schema prefixes?

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• code throws std::bad_alloc, not enough memory or can it be a bug?

  - by Andreas

  I am parsing using a pretty large grammar (1.1 GB, it's data-oriented parsing). The parser I use (bitpar) is said to be optimized for highly ambiguous grammars. I'm getting this error: 1terminate called after throwing an instance of 'std::bad_alloc' what(): St9bad_alloc dotest.sh: line 11: 16686 Aborted bitpar -p -b 1 -s top -u unknownwordsm -w pos.dfsa /tmp/gsyntax.pcfg /tmp/gsyntax.lex arbobanko.test arbobanko.results Is there hope? Does it mean that it has ran out of memory? It uses about 15 GB before it crashes. The machine I'm using has 32 GB of RAM, plus swap as well. It crashes before outputting a single parse tree. The parser is an efficient CYK chart parser using bit vector representations; I presume it is already near the limit of memory efficiency. If it really requires too much memory I could sample from the grammar rules, but this will decrease parse accuracy of course.

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• Java: InitialContext.lookup(String) - what should the value o the parametr be?

  - by bguiz

  To instantiate a Stateful Session Bean inside of a JSP/ servlet, I am using: InitialContext ic = new InitialContext(); SomeStateful state = (SomeStateful) ic.lookup("java:comp/env/SomeStatefulBean"); Trial and error had me prefix the name of my EJB with java:comp/env/, so the above works (on Glassfish 2.1). However I want to know what the proper way to obtain this prefix is. Is there a CLI tool or function somewhere in the admin panel that will allow we to examine/ alter this? Is this platform/ application server dependant? Is there a setting within my ear, EJB-jar or war which I can examine or alter for this? (Forgive the beginner question) Thanks!

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• Strange error with CreateCompatibleDC

  - by sevaxx

  Maybe this is a foolish question, I can't see why I can not get a DC created in the following code : HBITMAP COcrDlg::LoadClippedBitmap(LPCTSTR pathName,UINT maxWidth,UINT maxHeight) { HBITMAP hBmp = (HBITMAP)::LoadImage(NULL, pathName, IMAGE_BITMAP, 0, 0, LR_LOADFROMFILE | LR_CREATEDIBSECTION); if (!hBmp) return NULL; HDC hdc = (HDC)GetDC(); HDC hdcMem = CreateCompatibleDC(hdc); if (!hdcMem) { DWORD err = GetLastError(); } ... ... ... The bitmap hBmp is loaded fine and hdc has a valid value. But the call to CreateCompatibleDC() returns a NULL pointer. Then, GetLastError() returns 0 ! Anybody can guess what's going on here , please ? PS : There are no memory allocations or GDI routines called before this one...so I think memory leaks should be ruled out.

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• DataGrid: How to style or disable the default ContextMenu of a Cell

  - by Nike

  I use DataGrid with DataGridTextColumns. How can I style or disable the default ContextMenu of a Cell? I tried to add a style for DataGridCell: <DataGrid.CellStyle> <Style TargetType="{x:Type DataGridCell}"> <Setter Property="ContextMenu" Value="{x:Null}"/> </Style> </DataGrid.CellStyle> but it doesn't work. As I understand, it is a TextBox inside a Cell when the Cell in edit mode. I tried also to add a style for TextBox, but it have an effect only on TextBoxes in XAML, but not on the DataGrid cells.

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• Android: Having trouble creating a subclass of application to share data with multiple Activities

  - by Mike

  Hello, I just finished a couple of activities in my game and now I was going to start to wire them both up to use real game data, instead of the test data I was using just to make sure each piece worked. Since multiple Activities will need access to this game data, I started researching the best way to pass this data to my Activities. I know about using putExtra with intents, but my GameData class has quite a bit of data and not just simple key value pairs. Besides quite a few basic data types, it also has large arrays. I didn't really want to try and pass all that, unless I can pass the entire object, instead of just key/data pairs. I read the following post and thought it would be the way to go, but so far, I haven't got it to work. Android: How to declare global variables? I created a simple test app to try this method out, but it keeps crashing and my code seems to look the same as in the post above - except I changed the names. Here is the error I am getting. Can someone help me understand what I am doing wrong? 12-23 00:50:49.762: ERROR/AndroidRuntime(608): Caused by: java.lang.ClassCastException: android.app.Application It crashes on the following statement: GameData newGameData = ((GameData)getApplicationContext()); Here is my code: package mrk.examples.StaticGameData; import android.app.Application; public class GameData extends Application { private int intTest; GameData () { intTest = 0; } public int getIntTest(){ return intTest; } public void setIntTest(int value){ intTest = value; } } // My main activity package mrk.examples.StaticGameData; import android.app.Activity; import android.content.Intent; import android.os.Bundle; import android.util.Log; public class StaticGameData extends Activity { int intStaticTest; /** Called when the activity is first created. */ @Override public void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); setContentView(R.layout.main); GameData newGameData = ((GameData)getApplicationContext()); newGameData.setIntTest(0); intStaticTest = newGameData.getIntTest(); Log.d("StaticGameData", "Well: IntStaticTest = " + intStaticTest); newGameData.setIntTest(1); Log.d("StaticGameData", "Well: IntStaticTest = " + intStaticTest + " newGameData: " + newGameData.getIntTest()); Intent intentNew = new Intent(this, PassData2Activity.class); startActivity (intentNew); } } // My test Activity to see if it can access the data and its previous state from the last activity package mrk.examples.StaticGameData; import android.app.Activity; import android.os.Bundle; import android.util.Log; public class PassData2Activity extends Activity { @Override public void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); setContentView(R.layout.main); GameData gamedataPass = ((GameData)getApplicationContext()); Log.d("PassData2Activity", "IntTest = " + gamedataPass.getIntTest()); } } Below is the relevant portion of my manifest: <application android:icon="@drawable/icon" android:label="@string/app_name"> <activity android:name=".StaticGameData" android:label="@string/app_name"> <intent-filter> <action android:name="android.intent.action.MAIN" /> <category android:name="android.intent.category.LAUNCHER" /> </intent-filter> </activity> <activity android:name=".PassData2Activity"></activity> </application> <application android:name=".GameData" android:icon="@drawable/icon" android:label="@string/app_name"> </application> Thanks in advance for helping me understand why this code is crashing. Also, if you think this is just the wrong approach to let multiple activities have access to the same data, please give your suggestion. Please keep in mind that I am talking about quite a few variables and some large arrays.

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• standard C++ grammar

  - by eSKay

  Does the standard specify the official C++ grammar? I searched, but did not find it anywhere. Also, I wish to read a bit about C++ grammar in detail, like which category of grammars it falls in, etc. Any links pointing me in the right direction would be helpful. By category, I meant

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• Service not able to access a mapped drive.

  - by Rohit

  Hi All, I have read in many forums that mapped drives are not accessible from a service as no user is logged on. Question 1) I tried making my service as a log on - as some account and i had my network drive mapped in that very account. The service still cannot access it. Why? Question 2) From the same sevice, i invoke another process. Under what user account will the process run? Thanks

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• How do LL(*) parsers work?

  - by freezer878

  I cannot find any complete description about LL(*) parser, such as ANTLR, on Internet. I'm wondering what is the difference between an LL(k) parser and an LL(*) one and why they can't support left-recusrive grammars despite their flexibility.

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• cannot convert ‘mcontext_t*’ to ‘sigcontext*’ in assignment

  - by user353573

  i have checked asm/ucontext.h it should be sigcontext, but why pop up the error message cannot convert ‘mcontext_t*’ to ‘sigcontext*’ in assignment #include <stdio.h> #include <signal.h> #include <asm/ucontext.h> static unsigned long target; void handler(int signum, siginfo_t *siginfo, void *uc0){ struct ucontext *uc; struct sigcontext *sc; uc = (struct ucontext *)uc0; sc = &uc->uc_mcontext; sc->eip = target; } struct ucontext { unsigned long uc_flags; struct ucontext *uc_link; stack_t uc_stack; struct sigcontext uc_mcontext; sigset_t uc_sigmask; /* mask last for extensibility */ };

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• SQL SERVER – Fix : Error : 8501 MSDTC on server is unavailable. Changed database context to publishe

  - by pinaldave

  During configuring replication on one of the server, I received following error. This is very common error and the solution of the same is even simpler. MSDTC on server is unavailable. Changed database context to publisherdatabase. (Microsoft SQL Server, Error: 8501) Solution: Enable “Distributed Transaction Coordinator” in SQL Server. Method 1: Click on Start–>Control Panel->Administrative Tools->Services Select the service “Distributed Transaction Coordinator” Right on the service and choose “Start” Method 2: Type services.msc in the run command box Select “Services” manager; Hit Enter Select the service “Distributed Transaction Coordinator” Right on the service and choose “Start” Reference : Pinal Dave (http://blog.SQLAuthority.com) Filed under: Pinal Dave, SQL, SQL Authority, SQL Error Messages, SQL Query, SQL Scripts, SQL Server, SQL Tips and Tricks, T SQL, Technology Tagged: SQL Replication

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• Drop outs when accessing share by DFS name.

  - by Stephen Woolhead

  I have a strange problem, aren't they all! I have a DFS root \domain\files\vms, it has a single target on a different server than the namespace. I can copy a test file set from the target directly via \server\vms$\testfiles and all is well, the files copy fine. I have repeated these tests many times. If I try and copy the files from the dfs root I get big pauses in the network traffic, about 50 seconds every couple of minutes, all the traffic just stops for the copy. If I start another copy between the same two machines during this pause, it starts copying fine, so I know it's not an issue with the disks on the server. Every once in a while the copy will fail, no errors, the progress bar will just zip all the way to 100% and the copy dialog will close. Checking the target folder show that the copy is incomplete. I've moved the LUN to another server and had the same problem. The servers are all 2008 R2, the clients are Vista x64, Windows7 x64 and 2008 R2, all have the same problem. Anyone got any ideas? Cheers, Stephen More Information: I've been running a NetMon trace on the connection when the file copy fails and what seems to be standing out is that when opening a file that the copy completes on the SMB command looks like this: SMB2: C CREATE (0x5), Name=Training\PDC2008\BB34 Live Services Notifications, Awareness, and Communications.wmv@#422082, Context=DHnQ, Context=MxAc, Context=QFid, Context=RqLs, Mid = 245376 SMB2: R CREATE (0x5), Context=MxAc, Context=RqLs, Context=DHnQ, Context=QFid, FID=0xFFFFFFFF00000015, Mid = 245376 But for the last file when the copy dialog closes looks like this: SMB2: C CREATE (0x5), Name=gt\files\Media\Training\PDC2008\BB36 FAST Building Search-Driven Portals with Microsoft Office SharePoint Server 2007 and Microsoft Silverlight.wmv@#859374, Context=DHnQ, Context=MxAc, Context=QFid, Context=RqLs, Mid = 77 SMB2: R , Mid = 77 - NT Status: System - Error, Code = (58) STATUS_OBJECT_PATH_NOT_FOUND The main difference seems to be in the name, one is relative to the open file share, the other has gained the gt\files\media prefix which is the name of the DFS target. These failures are always preceded by logoff and back on of the SMB target. Might have to bump this one to PSS.

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• Is context inheritance, as shown by Head First Design Patterns' Duck example, irrelevant to strategy pattern?

  - by Korey Hinton

  In Head First Design Patterns it teaches the strategy pattern by using a Duck example where different subclasses of Duck can be assigned a particular behavior at runtime. From my understanding the purpose of the strategy pattern is to change an object's behavior at runtime. Emphasis on "an" meaning one. Could I further simplify this example by just having a Duck class (no derived classes)? Then when implementing one duck object it can be assigned different behaviors based on certain circumstances that aren't dependent on its own object type. For example: FlyBehavior changes based on the weather or QuackBehavior changes based on the time of day or how hungry a duck is. Would my example above constitute the strategy pattern as well? Is context inheritance (Duck) irrelevant to the strategy pattern or is that the reason for the strategy pattern? Here is the UML diagram from the Head First book:

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• In this context with views in a tree, which class should perform the task?

  - by Jhonny 8

  Imagine that I have this context: A main view containing a table containing some cells. Each one of them with their own controller and view files. In the main view, I have an object "Person", with 3 different IDs. Depending on certain conditions (let say, time of the day), I have to choose one of them and display it in the cell. My question is, should the main view pass the whole object to the table, and this one to the cell, and the cell will calculate the ID that it will be shown? or, The main view calculates this parameter, and send the result to the table and this to the cell? Is a question focused on OO design, which one of this approaches is more suitable in an OO design and why?

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• What the best way to wire up Entity Framework database context (model) to ViewModel in MVVM WPF?

  - by hal9k2

  As in the question above: What the best way to wire up Entity Framework database model (context) to viewModel in MVVM (WPF)? I am learning MVVM pattern in WPF, alot of examples shows how to implement model to viewModel, but models in that examples are just simple classes, I want to use MVVM together with entity framework model (base first approach). Whats the best way to wire model to viewModel. Thanks for answers. //ctor of ViewModel public ViewModel() { db = new PackageShipmentDBEntities(); // Entity Framework generated class ListaZBazy = new ObservableCollection<Pack>(db.Packs.Where(w => w.IsSent == false)); } This is my usual ctor of ViewModel, think there is a better way, I was reading about repository pattern, not sure if I can adapt this to WPF MVVM

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• SQL SERVER Fix : Error : 8501 MSDTC on server is unavailable. Changed database context to publisher

  During configuring replication on one of the server, I received following error. This is very common error and the solution of the same is even simpler.MSDTC on server is unavailable. Changed database context to publisherdatabase. (Microsoft SQL Server, Error: 8501)Solution:Enable Distributed Transaction Coordinator in SQL Server.Method 1:Click on StartControl Panel-Administrative Tools-ServicesSelect the service [...]...Did you know that DotNetSlackers also publishes .net articles written by top known .net Authors? We already have over 80 articles in several categories including Silverlight. Take a look: here.

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• What are the benefits of Android way of "saving memory" - explicitly passing Context objects everywhere?

  - by Sarge Borsch

  Turned out, this question is not easy to formulate for me, but let's try. In Android, pretty much any UI object depends on a Context, and has defined lifetime. It also can destroy and recreate UI objects and even whole application process at any time, and so on. This makes coding asynchronous operations correctly not straightforward. (and sometimes very cumbersome) But I never have seen a real explanation, why it's done that way? There are other OSes, including mobile OSes (iOS, for example), that don't do such things. So, what are the wins of Android way (Activities & Contexts)? Does that allow Android applications to use much less RAM, or maybe there are other benefits?

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• how to remove an item from my context menu?

  - by mongoose_za

  I installed a program called Aptana Studio 3. It's added a menu item to my context menu(if I right click I see an option "Aptana Studio"). How can I manually remove this from my menu? I have searched high and low and can't find a way to remove the Aptana stuff from my Firefox. Perhaps it's because I'm on Firefox 4. What I have done is I've gone into about:config I then searched for Aptana and there are 3 items that are listed. I've attached a screenshot. My question now is how can I remove these items because perhaps this will remove the option from my menu.

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• What is the best way to work with large databases in Java depending on context?

  - by user19000

  We are trying to figure out the best practice for working with very large DBs in Java. What we do is a kind of BI (business Intelligence), i.e analyzing very large DBs, and using them to create intermediate DBs that represent intelligent knowledge of the DBs. We are currently using JDBC, and just preforming queries using a ResultSet. As more and more data is being created, we are wondering whether more appropriate ways exist for parsing and manipulating these large DBs: We need to support 'chunk' manipulation and not an entire DB at once(e.g. limit in JDBC, very poor performance) We do not need to be constantly connected since we are just pulling results and creating new tables of our own. We want to understand JDBC alternatives, with respect to advantages and disadvantages. Whether you think JDBC is the way to go or not, what are the best practices to go by depending on context (e.g. for large DBs queried in chunks)?

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• HttpContext.Items and Server.Transfer/Execute

  - by Rick Strahl

  A few days ago my buddy Ben Jones pointed out that he ran into a bug in the ScriptContainer control in the West Wind Web and Ajax Toolkit. The problem was basically that when a Server.Transfer call was applied the script container (and also various ClientScriptProxy script embedding routines) would potentially fail to load up the specified scripts. It turns out the problem is due to the fact that the various components in the toolkit use request specific singletons via a Current property. I use a static Current property tied to a Context.Items[] entry to handle this type of operation which looks something like this: /// <summary> /// Current instance of this class which should always be used to /// access this object. There are no public constructors to /// ensure the reference is used as a Singleton to further /// ensure that all scripts are written to the same clientscript /// manager. /// </summary> public static ClientScriptProxy Current { get { if (HttpContext.Current == null) return new ClientScriptProxy(); ClientScriptProxy proxy = null; if (HttpContext.Current.Items.Contains(STR_CONTEXTID)) proxy = HttpContext.Current.Items[STR_CONTEXTID] as ClientScriptProxy; else { proxy = new ClientScriptProxy(); HttpContext.Current.Items[STR_CONTEXTID] = proxy; } return proxy; } } The proxy is attached to a Context.Items[] item which makes the instance Request specific. This works perfectly fine in most situations EXCEPT when you’re dealing with Server.Transfer/Execute requests. Server.Transfer doesn’t cause Context.Items to be cleared so both the current transferred request and the original request’s Context.Items collection apply. For the ClientScriptProxy this causes a problem because script references are tracked on a per request basis in Context.Items to check for script duplication. Once a script is rendered an ID is written into the Context collection and so considered ‘rendered’: // No dupes - ref script include only once if (HttpContext.Current.Items.Contains( STR_SCRIPTITEM_IDENTITIFIER + fileId ) ) return; HttpContext.Current.Items.Add(STR_SCRIPTITEM_IDENTITIFIER + fileId, string.Empty); where the fileId is the script name or unique identifier. The problem is on the Transferred page the item will already exist in Context and so fail to render because it thinks the script has already rendered based on the Context item. Bummer. The workaround for this is simple once you know what’s going on, but in this case it was a bitch to track down because the context items are used in many places throughout this class. The trick is to determine when a request is transferred and then removing the specific keys. The first issue is to determine if a script is in a Trransfer or Execute call: if (HttpContext.Current.CurrentHandler != HttpContext.Current.Handler) Context.Handler is the original handler and CurrentHandler is the actual currently executing handler that is running when a Transfer/Execute is active. You can also use Context.PreviousHandler to get the last handler and chain through the whole list of handlers applied if Transfer calls are nested (dog help us all for the person debugging that). For the ClientScriptProxy the full logic to check for a transfer and remove the code looks like this: /// <summary> /// Clears all the request specific context items which are script references /// and the script placement index. /// </summary> public void ClearContextItemsOnTransfer() { if (HttpContext.Current != null) { // Check for Server.Transfer/Execute calls - we need to clear out Context.Items if (HttpContext.Current.CurrentHandler != HttpContext.Current.Handler) { List<string> Keys = HttpContext.Current.Items.Keys.Cast<string>().Where(s => s.StartsWith(STR_SCRIPTITEM_IDENTITIFIER) || s == STR_ScriptResourceIndex).ToList(); foreach (string key in Keys) { HttpContext.Current.Items.Remove(key); } } } } along with a small update to the Current property getter that sets a global flag to indicate whether the request was transferred: if (!proxy.IsTransferred && HttpContext.Current.Handler != HttpContext.Current.CurrentHandler) { proxy.ClearContextItemsOnTransfer(); proxy.IsTransferred = true; } return proxy; I know this is pretty ugly, but it works and it’s actually minimal fuss without affecting the behavior of the rest of the class. Ben had a different solution that involved explicitly clearing out the Context items and replacing the collection with a manually maintained list of items which also works, but required changes through the code to make this work. In hindsight, it would have been better to use a single object that encapsulates all the ‘persisted’ values and store that object in Context instead of all these individual small morsels. Hindsight is always 20/20 though :-}. If possible use Page.Items ClientScriptProxy is a generic component that can be used from anywhere in ASP.NET, so there are various methods that are not Page specific on this component which is why I used Context.Items, rather than the Page.Items collection.Page.Items would be a better choice since it will sidestep the above Server.Transfer nightmares as the Page is reloaded completely and so any new Page gets a new Items collection. No fuss there. So for the ScriptContainer control, which has to live on the page the behavior is a little different. It is attached to Page.Items (since it’s a control): /// <summary> /// Returns a current instance of this control if an instance /// is already loaded on the page. Otherwise a new instance is /// created, added to the Form and returned. /// /// It's important this function is not called too early in the /// page cycle - it should not be called before Page.OnInit(). /// /// This property is the preferred way to get a reference to a /// ScriptContainer control that is either already on a page /// or needs to be created. Controls in particular should always /// use this property. /// </summary> public static ScriptContainer Current { get { // We need a context for this to work! if (HttpContext.Current == null) return null; Page page = HttpContext.Current.CurrentHandler as Page; if (page == null) throw new InvalidOperationException(Resources.ERROR_ScriptContainer_OnlyWorks_With_PageBasedHandlers); ScriptContainer ctl = null; // Retrieve the current instance ctl = page.Items[STR_CONTEXTID] as ScriptContainer; if (ctl != null) return ctl; ctl = new ScriptContainer(); page.Form.Controls.Add(ctl); return ctl; } } The biggest issue with this approach is that you have to explicitly retrieve the page in the static Current property. Notice again the use of CurrentHandler (rather than Handler which was my original implementation) to ensure you get the latest page including the one that Server.Transfer fired. Server.Transfer and Server.Execute are Evil All that said – this fix is probably for the 2 people who are crazy enough to rely on Server.Transfer/Execute. :-} There are so many weird behavior problems with these commands that I avoid them at all costs. I don’t think I have a single application that uses either of these commands… Related Resources Full source of ClientScriptProxy.cs (repository) Part of the West Wind Web Toolkit Static Singletons for ASP.NET Controls Post © Rick Strahl, West Wind Technologies, 2005-2010Posted in ASP.NET  

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