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  • Moving .NET assemblies away from the application base directory?

    - by RasmusKL
    I have a WinForms application with a bunch of third party references. This makes the output folder quite messy. I'd like to place the compiled / referenced dlls into a common subdirectory in the output folder, bin / lib - whatever - and just have the executables (+ needed configs etc) reside in the output folder. After some searching I ran into assembly probing (http://msdn.microsoft.com/en-us/library/4191fzwb.aspx) - and verified that if I set this up and manually move the assemblies my application will still work if they are stored in the designated subdirectory like so: <configuration> <runtime> <assemblyBinding xmlns="urn:schemas-microsoft-com:asm.v1"> <probing privatePath="bin" /> </assemblyBinding> </runtime> </configuration> However, this doesn't solve the build part - is there any way to specify where referenced assemblies and compiled library assemblies go? Only solutions I can think of off the top of my head is either post-build actions or dropping the idea and using ILMerge or something. There has got to be a better way of defining the structure :-)

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  • Ideas on frameworks in .NET that can be used for job processing and notifications

    - by Rajat Mehta
    Scenario: We have one instance of WCF windows service which exposes contracts like: AddNewJob(Job job), GetJobs(JobQuery query) etc. This service is consumed by 70-100 instances of client which is Windows Form based .NET app. Typically the service has 50-100 inward calls/minute to add or query jobs that are stored in a table on Sql Server. The same service is also responsible for processing these jobs in real time. It queries database every 5 seconds picks up the queued jobs and starts processing them. A job has 6 states. Queued, Pre-processing, Processing, Post-processing, Completed, Failed, Locked. Another responsibility on this service is to update all clients on every state change of every job. This means almost 200+ callbacks to clients per second. Question: This whole implementation is done using WCF Duplex bindings and works perfectly fine on small number of parallel jobs. Problem arises when we scale it up to 1000 jobs at a time. The notifications don't work as expected, it leads to memory overflow etc. Is there any standard framework that can provide a clean infrastructure for handling this scenario?? Apologies for the long explanation!

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  • How to safely transfer reference to object across window?

    - by Morgan Cheng
    I'm debugging a web application. Javasript in one window create one object and use it as argument to invoke global method in another window. Pseudo code is like below. var obj = new Foo(); anotherWin.bar(obj); In anotherWin, the argument is stored in global variable. var g_obj; function bar(obj) { g_obj = obj; ... } When other function tries to reference g_obj.Id, it throws exception "Cannot evaluate expression". This happens in IE8.0.7600.16385 on Windows 7. In Visual Studio debugger, when this exception happens, the g_obj shows as {...} It looks all its properties are lost. Perhaps the root reason is the object is created in one window but only referenced in another window. The object might be garbage-collected at any time. Is there any way to work around this?

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  • I need to get form data from multiple forms on one page using $_POST

    - by CDeanMartin
    My project is a menu that displays daily specials at a cafe. The Pointy Haired Boss(PHB) needs to add/remove items from the menu on a daily basis, so I stored all dishes with MySQL, and created a page which will load all menu items as buttons. When clicked, the button will UPDATE the item, turning it on or off. I need form data to detect which button was pressed, so my query knows which $menuItem to UPDATE. That is the purpose of the hidden fields. <html><head></head> <body> <html><head></head> <body> <?php include("getElement.php"); $keys = array_keys($_POST); echo $keys[0]; echo $keys[1]; //if(isset($_POST["menuItem"])){ //toggleItem($_POST["menuItem"]); //echo print_r(array_keys($_POST));} ?> <form name="b" action="scratchpad.php" method="post" > <input type="hidden" name="b" value="Cajun Gumbo"/> <input type="submit" style="color:blue" value="Cajun Gumbo" /> </form> <form name="a" action="scratchpad.php" method="post" > <input type="hidden" name="a" value="Guacomole Burger"/> <input type="submit" style="color:blue" value="Guacomole Burger" /> </form> </body> </html> Can I get $_POST to identify which button was pressed?

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  • Why Can I Change Struct's int[] Property from Method Without Specifying "ref"?

    - by AMissico
    From a method, I can pass a struct which contains an array of integers, and change the values in the array. I am not sure I understand fully why I can do this. Can someone please explain why I can change the values stored in the int[]? private void DoIt(){ SearchInfo a = new SearchInfo(); a.Index = 1; a.Map = new int[] { 1 }; SearchInfo b = new SearchInfo(); b.Index = 1; b.Map = new int[] { 1 }; ModifyA(a); ModifyB(ref b); Debug.Assert(a.Index == 1); Debug.Assert(a.Map[0] == 1, "why did this change?"); Debug.Assert(b.Index == 99); Debug.Assert(b.Map[0] == 99); } void ModifyA(SearchInfo a) { a.Index = 99; a.Map[0] = 99; } void ModifyB(ref SearchInfo b) { b.Index = 99; b.Map[0] = 99; } struct SearchInfo { public int[] Map; public int Index; }

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  • Why is my UIWebView not scrollable?

    - by Thomas
    In my most frustrating roadblock to date, I've come across a UIWebView that will NOT scroll! I call it via this IBAction: -(IBAction)session2ButtonPressed:(id)sender { Session2ViewController *session2View = [[Session2ViewController alloc]initWithNibName:@"Session2ViewController" bundle:nil]; self.addictionViewController = session2View; [self.view insertSubview:addictionViewController.view atIndex:[self.view.subviews count]]; [session2View release]; } In the viewDidLoad of Session2ViewController.m, I have - (void)viewDidLoad { [super viewDidLoad]; // TRP - Grab data from plist // TRP - Build file path to the plist NSString *filePath = [[NSBundle mainBundle] pathForResource:@"Addiction" ofType:@"plist"]; // TRP - Create NSDictionary with contents of the plist NSDictionary *addictionDict = [NSDictionary dictionaryWithContentsOfFile:filePath]; // TRP - Create an array with contents of the dictionary NSArray *addictionData = [addictionDict objectForKey:@"Addiction1"]; NSLog(@"addictionData (array): %@", addictionData); // TRP - Create a string with the contents of the array NSString *addictionText = [NSString stringWithFormat:@"<DIV style='font-family:%@;font-size:%d;'>%@</DIV>", @"Helvetica", 18, [addictionData objectAtIndex:1]]; addictionInfo.backgroundColor = [UIColor clearColor]; // TRP - Load the string created and stored into addictionText and display in the UIWebView [addictionInfo loadHTMLString:addictionText baseURL:nil]; // TODO: MAKE THIS WEBVIEW SCROLL!!!!!! } In the nib, I connected my web view to the delegate and to the outlet. When I run my main project, the plist with my HTML code shows up, but does not scroll. I copied and pasted this code into a new project, wired the nib the exact same way, and badda-boom badda-bing. . . it works. I even tried to create a new nib from scratch in this project, and the exact same code would not work. Whiskey Tango Foxtrot Any ideas?? Thanks! Thomas

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  • using volatile keyword

    - by sap
    As i understand, if we declare a variable as volatile, then it will not be stored in the local cache. Whenever thread are updating the values, it is updated to the main memory. So, other threads can access the updated value. But in the following program both volatile and non-volatile variables are displaying same value. The volatile variable is not updated for the second thread. Can anybody plz explain this why testValue is not changed. class ExampleThread extends Thread { private int testValue1; private volatile int testValue; public ExampleThread(String str){ super(str); } public void run() { if (getName().equals("Thread 1 ")) { testValue = 10; testValue1= 10; System.out.println( "Thread 1 testValue1 : " + testValue1); System.out.println( "Thread 1 testValue : " + testValue); } if (getName().equals("Thread 2 ")) { System.out.println( "Thread 2 testValue1 : " + testValue1); System.out.println( "Thread 2 testValue : " + testValue); } } } public class VolatileExample { public static void main(String args[]) { new ExampleThread("Thread 1 ").start(); new ExampleThread("Thread 2 ").start(); } } output: Thread 1 testValue1 : 10 Thread 1 testValue : 10 Thread 2 testValue1 : 0 Thread 2 testValue : 0

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  • Version Control: multiple version hell, file synchronization

    - by SigTerm
    Hello. I would like to know how you normally deal with this situation: I have a set of utility functions. Say..5..10 files. And technically they are static library, cross-platform - SConscript/SConstruct plus Visual Studio project (not solution). Those utility functions are used in multiple small projects (15+, number increases over time). Each project has a copy of a few files or of an entire library, not a link into one central place. Sometimes project uses one file, two files, some use everything. Normally, utility functions are included as a copy of every file and SConscript/SConstruct or Visual Studio Project (depending on the situation). Each project has a separate git repository. Sometimes one project is derived from other, sometimes it isn't. You work on every one of them, in random order. There are no other people (to make things simpler) The problem arises when while working on one project you modify those utility function files. Because each project has a copy of file, this introduces new version, which leads to the mess when you try later (week later, for example) to guess which version has a most complete functionality (i.e. you added a function to a.cpp in one project, and added another function to a.cpp in another project, which created a version fork) How would you handle this situation to avoid "version hell"? One way I can think of is using symbolic links/hard links, but it isn't perfect - if you delete one central storage, it will all go to hell. And hard links won't work on dual-boot system (although symbolic links will). It looks like what I need is something like advanced git repository, where code for the project is stored in one local repository, but is synchronized with multiple external repositories. But I'm not sure how to do it or if it is possible to do this with git. So, what do you think?

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  • Long running transactions with Spring and Hibernate?

    - by jimbokun
    The underlying problem I want to solve is running a task that generates several temporary tables in MySQL, which need to stay around long enough to fetch results from Java after they are created. Because of the size of the data involved, the task must be completed in batches. Each batch is a call to a stored procedure called through JDBC. The entire process can take half an hour or more for a large data set. To ensure access to the temporary tables, I run the entire task, start to finish, in a single Spring transaction with a TransactionCallbackWithoutResult. Otherwise, I could get a different connection that does not have access to the temporary tables (this would happen occasionally before I wrapped everything in a transaction). This worked fine in my development environment. However, in production I got the following exception: java.sql.SQLException: Lock wait timeout exceeded; try restarting transaction This happened when a different task tried to access some of the same tables during the execution of my long running transaction. What confuses me is that the long running transaction only inserts or updates into temporary tables. All access to non-temporary tables are selects only. From what documentation I can find, the default Spring transaction isolation level should not cause MySQL to block in this case. So my first question, is this the right approach? Can I ensure that I repeatedly get the same connection through a Hibernate template without a long running transaction? If the long running transaction approach is the correct one, what should I check in terms of isolation levels? Is my understanding correct that the default isolation level in Spring/MySQL transactions should not lock tables that are only accessed through selects? What can I do to debug which tables are causing the conflict, and prevent those tables from being locked by the transaction?

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  • C# class design - expose variables for reading but not setting

    - by James Brauman
    I have a a polygon class which stores a list of Microsoft.Xna.Framework.Vector2 as the vertices of the polygon. Once the polygon is created, I'd like other classes to be able to read the position of the vertices, but not change them. I am currently exposing the vertices through this field: /// <summary> /// Gets the vertices stored for this polygon. /// </summary> public List<Vector2> Vertices { get { return _vertices; } } List<Vector2> _vertices; However you can change any vertex using code like: Polygon1.Vertices[0] = new Vector2(0, 0); or Polygon1.Vertices[0].X = 0; How can I limit other classes to be able to only read the properties of these vertices, and not be able to set a new one to my List? The only thing I can think of is to pass a copy to classes that request it. Note that Vector2 is a struct that is part of the XNA framework and I cannot change it. Thanks.

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  • TSQL - make a literal float value

    - by David B
    I understand the host of issues in comparing floats, and lament their use in this case - but I'm not the table author and have only a small hurdle to climb... Someone has decided to use floats as you'd expect GUIDs to be used. I need to retrieve all the records with a specific float value. sp_help MyTable -- Column_name Type Computed Length Prec -- RandomGrouping float no 8 53 Here's my naive attempt: --yields no results SELECT RandomGrouping FROM MyTable WHERE RandomGrouping = 0.867153569942739 And here's an approximately working attempt: --yields 2 records SELECT RandomGrouping FROM MyTable WHERE RandomGrouping BETWEEN 0.867153569942739 - 0.00000001 AND 0.867153569942739 + 0.00000001 -- 0.867153569942739 -- 0.867153569942739 In my naive attempt, is that literal a floating point literal? Or is it really a decimal literal that gets converted later? If my literal is not a floating point literal, what is the syntax for making a floating point literal? EDIT: Another possibility has occurred to me... it may be that a more precise number than is displayed is stored in this column. It may be impossible to create a literal that represents this number. I will accept answers that demonstrate that this is the case. EDIT: response to DVK. TSQL is MSSQLServer's dialect of SQL. This script works, and so equality can be performed deterministically between float types: DECLARE @X float SELECT top 1 @X = RandomGrouping FROM MyTable WHERE RandomGrouping BETWEEN 0.839110948199148 - 0.000000000001 AND 0.839110948199148 + 0.000000000001 --yields two records SELECT * FROM MyTable WHERE RandomGrouping = @X I said "approximately" because that method tests for a range. With that method I could get values that are not equal to my intended value. The linked article doesn't apply because I'm not (intentionally) trying to straddle the world boundaries between decimal and float. I'm trying to work with only floats. This isn't about the non-convertibility of decimals to floats.

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  • Convert SQL with Inner AND Outer Join to L2S

    - by Refracted Paladin
    I need to convert the below Sproc to a Linq query. At the very bottom is what I have so far. For reference the fields behind the "splat"(not my sproc) are ImmunizationID int, HAReviewID int, ImmunizationMaintID int, ImmunizationOther varchar(50), ImmunizationDate smalldatetime, ImmunizationReasonID int The first two are PK and FK, respectively. The other two ints are linke to the Maint Table where there description is stored. That is what I am stuck on, the INNER JOIN AND the LEFT OUTER JOIN Thanks, SELECT tblHAReviewImmunizations.*, tblMaintItem.ItemDescription, tblMaintItem2.ItemDescription as Reason FROM dbo.tblHAReviewImmunizations INNER JOIN dbo.tblMaintItem ON dbo.tblHAReviewImmunizations.ImmunizationMaintID = dbo.tblMaintItem.ItemID LEFT OUTER JOIN dbo.tblMaintItem as tblMaintItem2 ON dbo.tblHAReviewImmunizations.ImmunizationReasonID = tblMaintItem2.ItemID WHERE HAReviewID = @haReviewID My attempt so far -- public static DataTable GetImmunizations(int haReviewID) { using (var context = McpDataContext.Create()) { var currentImmunizations = from haReviewImmunization in context.tblHAReviewImmunizations where haReviewImmunization.HAReviewID == haReviewID join maintItem in context.tblMaintItems on haReviewImmunization.ImmunizationReasonID equals maintItem.ItemID into g from maintItem in g.DefaultIfEmpty() let Immunization = GetImmunizationNameByID( haReviewImmunization.ImmunizationMaintID) select new { haReviewImmunization.ImmunizationDate, haReviewImmunization.ImmunizationOther, Immunization, Reason = maintItem == null ? " " : maintItem.ItemDescription }; return currentImmunizations.CopyLinqToDataTable(); } } private static string GetImmunizationNameByID(int? immunizationID) { using (var context = McpDataContext.Create()) { var domainName = from maintItem in context.tblMaintItems where maintItem.ItemID == immunizationID select maintItem.ItemDescription; return domainName.SingleOrDefault(); } }

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  • Need some help with a MySQL subquery count

    - by Ferdy
    I'm running into my own limits of MySQL query skills, so I hope some SQL guru can help out on this one. The situation is as follow: I have images that can be tagged. As you might expect this is stored in three tables: Image Tag Tag_map (maps images to tags) I have a SQL query that calculates the related tags based on a tag id. The query basically checks what other tags were used for images for images using that tag. Example: Image1 tagged as "Bear" Image2 tagged as "Bear" and "Canada" If I throw "Bear" (or its tag id) at the query, it will return "Canada". This works fine. Here's the query: SELECT tag.name, tag.id, COUNT(tag_map.id) as cnt FROM tag_map,tag WHERE tag_map.tag_id = tag.id AND tag.id != '185' AND tag_map.image_id IN (SELECT tag_map.image_id FROM tag_map INNER JOIN tag ON tag_map.tag_id = tag.id WHERE tag.id = '185') GROUP BY tag_map.id LIMIT 0,100 The part I'm stuck with is the count. For each related tag returned, I want to know how many images are in that tag. Currently it always returns 1, even if there are for example 3. I've tried counting different columns all resulting in the same output, so I guess there is a flaw in my thinking.

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  • How to upload files and store them in a server local path when MS SQL SERVER allows remote connectio

    - by user193655
    I am developing a win32 windows application with Delphi and MS SQL Server. it works fine in LAN but I am trying to add the support for SQL Server remote connections (= working with a DB that can be accessed with an external IP, as described in this article: http://support.microsoft.com/default.aspx?scid=kb;EN-US;914277). Basically I have a Table in DB where I keep the DocumentID, the document description and the Document path (like \FILESERVER\MyApplicationDocuments\45.zip). Of course \FILESERVER is a local (LAN) path for the server but not for the client (as I am now trying to add the support for remote connections). So I need a way to access \FILESERVER even if of course I cannot see it in LAN. I found the following T-SQL code snippet that is perfect for the "download trick": SELECT BulkColumn as MyFile FROM OPENROWSET(BULK '\FILESERVER\MyApplicationDocuments\45.zip' , SINGLE_BLOB) AS X With the code above I can download a file on the client. But how to upload it? I need an "Uppload trick" to be able to insert new files, but also to delete or replace existing files. Can anyone suggest? If a trick is not available could you suggest an alternative? Like an extended stored procedure or calling some .net assembly from the server.

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  • Select all points in a matrix within 30m of another point

    - by pinnacler
    So if you look at my other posts, it's no surprise I'm building a robot that can collect data in a forest, and stick it on a map. We have algorithms that can detect tree centers and trunk diameters and can stick them on a cartesian XY plane. We're planning to use certain 'key' trees as natural landmarks for localizing the robot, using triangulation and trilateration among other methods, but programming this and keeping data straight and efficient is getting difficult using just Matlab. Is there a technique for sub-setting an array or matrix of points? Say I have 1000 trees stored over 1km (1000m), is there a way to say, select only points within 30m radius of my current location and work only with those? I would just use a GIS, but I'm doing this in Matlab and I'm unaware of any GIS plugins for Matlab. I forgot to mention, this code is going online, meaning it's going on a robot for real-time execution. I don't know if, as the map grows to several miles, using a different data structure will help or if calculating every distance to a random point is what a spatial database is going to do anyway. I'm thinking of mirroring two arrays, one sorted by X and the other by Y. Then bubble sorting to determine the 30m range in that. I do the same for both arrays, X and Y, and then have a third cross link table that will select the individual values. But I don't know, what that's called, how to program that and I'm sure someone already has so I don't want to reinvent the wheel. Cartesian Plane GIS

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  • Synchronizing Access to a member of the ASP.NET session

    - by Sam
    I'm building a Javascript application and eash user has an individual UserSession. The application makes a bunch of Ajax calls. Each Ajax call needs access to a single UserSession object for the user. Each Ajax call needs a UserSession object. Data in the UserSession object is unique to each user. Originally, during each Ajax call I would create a new UserSession object and it's data members were stored in the ASP.NET Session. However, I found that the UserSession object was being instantiated a lot. To minimize the construction of the UserSession object, I wrapped it in a Singleton pattern and sychronized access to it. I believe that the synchronization is happening application wide, however I only need it to happen per user. I saw a post here that says the ASP.NET cache is synchronized, however the time between creating the object and inserting it into the cache another Thread could start construction it's another object and insert it into the cache. Here is the way I'm currently synchronizing access to the object. Is there a better way than using "lock"... should be be locking on the HttpContext.Session object? private static object SessionLock = new object(); public static WebSession GetSession { get { lock (SessionLock) { try { var context = HttpContext.Current; WebSession result = null; if (context.Session["MySession"] == null) { result = new WebSession(context); context.Session["MySession"] = result; } else { result = (WebSession)context.Session["MySession"]; } return result; } catch (Exception ex) { ex.Handle(); return null; } } } }

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  • Using StructureMap to create classes by a name?

    - by Bevan
    How can I use StructureMap to resolve to an appropriate implementation of an interface based on a name stored in an attribute? In my project, I have many different kinds of widgets, each descending from IWidget, and each decorated with an attribute specifying the kind of associated element. To illustrate: [Configuration("header")] public class HeaderWidget : IWidget { } [Configuration("linegraph")] public class LineGraphWidget : IWidget { } When processing my (XML) configuration file, I want to obtain an instance of the appropriate concrete class based on the name of the element I'm processing. public IWidget CreateWidget(XElement definition) { var kind = definition.Name.LocalName; var widget = // What goes here? widget.Configure(definition); return widget; } Each definition should result in a different widget being created - I don't need or want the instances to be shared. In the past I've written plenty of code to do this kind of thing manually, including writing a custom "roll-your-own" IoC container for one project. However, one of my goals with this project is to become proficient with StructureMap instead of reinventing the wheel. I think I've already managed to set up automatic scanning of assemblies so that StructureMap knows about all my IWidget implementations: public class WidgetRegistration : Registry { public WidgetRegistration() { Scan( scanner => { scanner.AssembliesFromApplicationBaseDirectory(); scanner.AddAllTypesOf<IWidget>(); }); } } However, this isn't registering the names of my widgets with StructureMap. What do I need to add to make my scenario work? (While I am trying to use StructureMap in this project, an answer showing me how to solve this problem with a different DI/IoC tool would still be valuable.)

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  • Is it possible to use SqlGeography with Linq to Sql?

    - by cofiem
    I've been having quite a few problems trying to use Microsoft.SqlServer.Types.SqlGeography. I know full well that support for this in Ling to Sql is not great. I've tried numerous ways, beginning with what would the expected way (Database type of geography, CLR type of SqlGeography). This produces the NotSupportedException, which is widely discussed via blogs. I've then gone down the path of treating the geography column as a varbinary(max), as geography is a UDT stored as binary. This seems to work fine (with some binary reading and writing extension methods). However, I'm now running into a rather obscure issue, which does not seem to have happened to many other people. System.InvalidCastException: Unable to cast object of type 'Microsoft.SqlServer.Types.SqlGeography' to type 'System.Byte[]'. This error is thrown from an ObjectMaterializer when iterating through a query. It seems to only occur when the tables containing geography columns are included in a query implicitly (ie. using the EntityRef<> properties to do joins). System.Data.Linq.SqlClient.ObjectReaderCompiler.ObjectReader`2.MoveNext() My question: If I'm retrieving the geography column as varbinary(max), I might expect the reverse error: can't cast byte[] to SqlGeography. That I would understand. This I don't. I do have some properies on the partial LINQ to SQL classes that hide the binary conversion... could those be the issue? Any help appreciated, and I know there's probably not enough information.

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  • How to open the download window when a dynamically created link is clicked in asp.net

    - by Ranjana
    i have stored the txtfile in the database.i need to show the txtfile when i clik the link. and this link has to be created dynamically. my code below: aspx code: aspx.cs protected void Page_Load(object sender, EventArgs e) { if(!Page.IsPostBack) { DataTable dtassignment = new DataTable(); dtassignment = serviceobj.DisplayAssignment(Session["staffname"].ToString()); if (dtassignment != null) { Byte[] bytes = (Byte[])dtassignment.Rows[0]["Data"]; //download(dtassignment); } divlink.InnerHtml = ""; divlink.Visible = true; foreach (DataRow r in dtassignment.Rows) { divlink.InnerHtml += "<a href='" + "'onclick='download(dtassignment)'>" + r["Filename"].ToString() + "</a>" + "<br/>"; } } } - public void download(DataTable dtassignment) { System.Diagnostics.Debugger.Break(); Byte[] bytes = (Byte[])dtassignment.Rows[0]["Data"]; Response.Buffer = true; Response.Charset = ""; Response.Cache.SetCacheability(HttpCacheability.NoCache); Response.ContentType = dtassignment.Rows[0]["ContentType"].ToString(); Response.AddHeader("content-disposition", "attachment;filename=" + dtassignment.Rows[0]["FileName"].ToString()); Response.BinaryWrite(bytes); Response.Flush(); Response.End(); } i have got the link dynamically, but i did not able to download the txtfile when i clik the link. how to carry out this. pls help me out...

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  • C: 8x8 -> 16 bit multiply precision guaranteed by integer promotions?

    - by craig-blome
    I'm trying to figure out if the C Standard (C90, though I'm working off Derek Jones' annotated C99 book) guarantees that I will not lose precision multiplying two unsigned 8-bit values and storing to a 16-bit result. An example statement is as follows: unsigned char foo; unsigned int foo_u16 = foo * 10; Our Keil 8051 compiler (v7.50 at present) will generate a MUL AB instruction which stores the MSB in the B register and the LSB in the accumulator. If I cast foo to a unsigned int first: unsigned int foo_u16 = (unsigned int)foo * 10; then the compiler correctly decides I want a unsigned int there and generates an expensive call to a 16x16 bit integer multiply routine. I would like to argue beyond reasonable doubt that this defensive measure is not necessary. As I read the integer promotions described in 6.3.1.1, the effect of the first line shall be as if foo and 10 were promoted to unsigned int, the multiplication performed, and the result stored as unsigned int in foo_u16. If the compiler knows an instruction that does 8x8-16 bit multiplications without loss of precision, so much the better; but the precision is guaranteed. Am I reading this correctly? Best regards, Craig Blome

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  • general learning methodology

    - by momo
    just wanted to hear on the different general learning paths people embark on when learning a new language/framework. the one i currently use, which is how i learned bash and am currently learning python, is: instant hacking tutorial (very short tutorial introducing the basic syntax, variable declaration, loops, data types, etc. and how they are generally used) in depth tutorial with good programming style and slightly topic-specific (e.g. Mark Pilgrim's Dive into Python), important topics for me personally are regex methods, file IO, and ways the different data types are utilized best (i wrote a very primitive bayesian spam filter using python's dictionaries to keep track of word occurrences) spaced-repition of syntax or short recipes (i use anki, with questions like 'create dictionary with filename and filesize metadata, human-readable' or simpler ones like 'match 0 - 3 occurences of the letter M in a string', or 'return/create an iterator from two sequences') the use of spaced-repitition has been invaluable, and i credit it with the ease that i can recall/create python algorithms. however, i've recently started looking into django, and i've found that spaced-repitition, at least in my case, doesn't work very well for learning a framework, it works best with short code recipes (either that or i should start looking into more basic django framework tutorials). the problem i'm encountering is that since framework programming is not only algorithms, but actually learning the API, which can be quite complex since you have to learn all the methods, modules, the places where they are stored, and the sequence of which things have to be done. for ex. in django to start a project that deals with polls (from the django tutorial), one has to create the project, edit the settings.py file, create the polls app, edit the models.py file (which requires knowing the classes that are present in the module models), edit the urls.py file, etc. i found that my spaced-repition method didn't work very well for this type of learning, so i wanted to ask you guys what method(s) you use for learning the different frameworks/APIs.

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  • ASP.NET SqlDataReader throwing error: Invalid attempt to call Read when reader is closed.

    - by Bugget
    This one has me stumped. Here are the relative bits of code: public AgencyDetails(Guid AgencyId) { try { evgStoredProcedure Procedure = new evgStoredProcedure(); Hashtable commandParameters = new Hashtable(); commandParameters.Add("@AgencyId", AgencyId); SqlDataReader AppReader = Procedure.ExecuteReaderProcedure("evg_getAgencyDetails", commandParameters); commandParameters.Clear(); //The following line is where the error is thrown. Errormessage: Invalid attempt to call Read when reader is closed. while (AppReader.Read()) { AgencyName = AppReader.GetOrdinal("AgencyName").ToString(); AgencyAddress = AppReader.GetOrdinal("AgencyAddress").ToString(); AgencyCity = AppReader.GetOrdinal("AgencyCity").ToString(); AgencyState = AppReader.GetOrdinal("AgencyState").ToString(); AgencyZip = AppReader.GetOrdinal("AgencyZip").ToString(); AgencyPhone = AppReader.GetOrdinal("AgencyPhone").ToString(); AgencyFax = AppReader.GetOrdinal("AgencyFax").ToString(); } AppReader.Close(); AppReader.Dispose(); } catch (Exception ex) { throw new Exception("AgencyDetails Constructor: " + ex.Message.ToString()); } } And the implementation of ExecuteReaderProcedure: public SqlDataReader ExecuteReaderProcedure(string ProcedureName, Hashtable Parameters) { SqlDataReader returnReader; using (SqlConnection conn = new SqlConnection(connectionString)) { try { SqlCommand cmd = new SqlCommand(ProcedureName, conn); SqlParameter param = new SqlParameter(); cmd.CommandType = System.Data.CommandType.StoredProcedure; foreach (DictionaryEntry keyValue in Parameters) { cmd.Parameters.AddWithValue(keyValue.Key.ToString(), keyValue.Value); } conn.Open(); returnReader = cmd.ExecuteReader(CommandBehavior.CloseConnection); } catch (SqlException e) { throw new Exception(e.Message.ToString()); } } return returnReader; } The connection string is working as other stored procedures in the same class run fine. The only problem seems to be when returning SqlDataReaders from this method! They throw the error message in the title. Any ideas are greatly appreciated! Thanks in advance!

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  • Opening a pdf in .NET

    - by link664
    In the application we are working on we are trying to implement Help. We have a help pdf document and for the moment it has been deemed acceptable that when users click the help button it just opens the pdf. The application is a desktop app and the pdf file needs to be included in the install somehow and installed on the local machine. I essentially need two things: How would I add this pdf to the application so that it is available on the client machine after install? I can either put it in the resources of the project, or else I could put it in the Application Folder of the client setup installer. How would I open this pdf? I can either open this pdf by just launching the default pdf viewer for the file, or I can use the System.WinForms.WebBrowser tool to display it. However if I choose the second option, I am unsure of how to access the file stored in the resources or find it in the install folder. If you could please provide me with the code to do this (either in VB.Net or C#.Net) that would be great.

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  • Windows Azure - access webrole local storage from separate workerrole

    - by Brett Smith
    I'm running an application on windows azure, the MVC views need to be dynamic, I started by storing them as records in the database, but am quite keen to move them to a physical location. My concept was to create the physical file via code... which worked great and speeds up the page load dramatically. This was of course before I realised that the files were only available for the duration of the role Next I looked at a start up task to create the files when the role was started - however I then realised that any separate instances weren't going to sync up unless I monitored the database for changes. So I moved from a start up task to a function in the run method of the role that checks the database every 10 minutes to see if changes have occurred. The problem is that this seems to choke up the application (at least in the warm up stage). Ideally I would like to move the run function to it's own worker role that can sit there and push files out to web role instances, but I'm unsure on how I would go about accessing the web roles local storage from the worker role. Can anybody tell me whether this is actually possible? and hopefully point me in the right direction to achieve this? Just to clarify what I'm trying to achieve -View is created in user interface running on web role and stored in database -Separate web role (front end) has clientside application with virtualpath provider pointing Views requests to local storage (localresource) -separate worker role to create View structure and load this into clientside web role local storage

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  • What arguments to use to explain why a SQL DB is far better then a flat file

    - by jamone
    The higher ups in my company were told by good friends that flat files are the way to go, and we should switch from MS SQL server to them for everything we do. We have over 300 servers and hundreds of different databases. From just the few I'm involved with we have 10 billion records in quite a few of them with upwards of 100k new records a day and who knows how many updates... Me and a couple others need to come up with a response saying why we shouldn't do this. Most of our stuff is ASP.NET with some legacy ASP. We thought that making a simple console app that tests/times the same interactions between a flat file (stored on the network) and SQL over the network doing large inserts, searches, updates etc along with things like network disconnects randomly. This would show them how bad flat files can be espically when you are dealing with millions of records. What things should I use in my response? What should I do with my demo code to illustrate this? My sort list so far: Security Concurent access Performance with large ammounts of data Ammount of time to do such a massive rewrite/switch Lack of transactions PITA to map relational data to flat files I fear that this will be a great post on the Daily WTF someday if I can't stop it now.

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