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  • How to encapsulate a WinAPI application into a C++ class

    - by Semen Semenych
    There is a simple WinAPI application. All it does currently is this: register a window class register a tray icon with a menu create a value in the registry in order to autostart and finally, it checks if it's unique using a mutex As I'm used to writing code mainly in C++, and no MFC is allowed, I'm forced to encapsulate this into C++ classes somehow. So far I've come up with such a design: there is a class that represents the application it keeps all the wndclass, hinstance, etc variables, where the hinstance is passed as a constructor parameter as well as the icmdshow and others (see WinMain prototype) it has functions for registering the window class, tray icon, reigstry information it encapsulates the message loop in a function In WinMain, the following is done: Application app(hInstance, szCmdLIne, iCmdShow); return app.exec(); and the constructor does the following: registerClass(); registerTray(); registerAutostart(); So far so good. Now the question is : how do I create the window procedure (must be static, as it's a c-style pointer to a function) AND keep track of what the application object is, that is, keep a pointer to an Application around. The main question is : is this how it's usually done? Am I complicating things too much? Is it fine to pass hInstance as a parameter to the Application constructor? And where's the WndProc? Maybe WndProc should be outside of class and the Application pointer be global? Then WndProc invokes Application methods in response to various events.

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  • Is there an easier way to do Classic ASP "relative path"?

    - by Alex.Piechowski
    Right now, I'm having trouble. First of all I have a page, let's call it "http://blah.com/login". That obviously goes strait to "index.asp" A line of Main.asp: <!--#include file="resource/menu.asp"--> Page top includes all of what I need for my menu... so: Part of resource/menu.htm: <div id="colortab" class="ddcolortabs"> <ul> <li><a href="main.asp" title="Main" rel="dropmain"><span>Main</span></a></li> ... </ul> </div> <!--Main drop down menu --> <div id="dropmain" class="dropmenudiv_a"> <a href="main/announcements.asp">Announcements</a> <a href="main/contacts.asp">Contact Information</a> <a href="main/MeetingPlans.asp">Meeting Plan</a> <a href="main/photos.asp">Photo Gallery</a> <a href="main/events.asp">Upcoming Events</a> </div> Let's say I click on the "announcements" (http://blah.com/login/main/announcements.asp) link... Now I'm at the announcements page! But wait, I include the same menu file. Guess what happens: I get sent to "http://blah.com/login/main/main/announcements.asp Which doesn't exist... My solution: Make a menu_sub.asp include for any subpages. But wait a second... this WORKS, but it gets REALLY REALLY messy... What can I do to use just one main "menu.asp" instead of "menu_sub.asp"? using "/main/announcements.asp" WON'T be an option because this is a web application that will be on different directories per server. Any ideas? PLEASE

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  • What's an effective way to move data from one open browser tab to another?

    - by slk
    I am looking for a quick way to grab some data off of one Web page and throw it into another. I don't have access to the query string in the URL of the second page, so passing the data that way is not an option. Right now, I am using a Greasemonkey user script in tandem with a JS bookmarklet trigger: javascript:doIt(); // ==UserScript== // @include public_site // @include internal_site // ==/UserScript== if (document.location.host.match(internal_site)) { var datum1 = GM_getValue("d1"); var datum2 = GM_getValue("d2"); } unsafeWindow.doIt = function() { if(document.location.host.match(public_site)) { var d1 = innerHTML of page element 1; var d2 = innerHTML of page element 2; //Next two lines use setTimeout to bypass GM_setValue restriction window.setTimeout(function() {GM_setValue("d1", d1);}, 0); window.setTimeout(function() {GM_setValue("d2", d2);}, 0); } else if(document.location.host.match(internal_site)) { document.getElementById("field1").value = datum1; document.getElementById("field2").value = datum2; } } While I am open to another method, I would prefer to stay with this basic model if possible, as this is just a small fraction of the code in doIt() which is used on several other pages, mostly to automate date-based form fills; people really like their "magic button." The above code works, but there's an interruption to the workflow: In order for the user to know which page on the public site to grab data from, the internal page has to be opened first. Then, once the GM cookie is set from the public page, the internal page has to be reloaded to get the proper information into the internal page variables. I'm wondering if there's any way to GM_getValue() at bookmarklet-clicktime to prevent the need for a refresh. Thanks!

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  • Is it possible to replace values in a queryset before sending it to your template?

    - by Issy
    Hi Guys, Wondering if it's possible to change a value returned from a queryset before sending it off to the template. Say for example you have a bunch of records Date | Time | Description 10/05/2010 | 13:30 | Testing... etc... However, based on the day of the week the time may change. However this is static. For example on a monday the time is ALWAYS 15:00. Now you could add another table to configure special cases but to me it seems overkill, as this is a rule. How would you replace that value before sending it to the template? I thought about using the new if tags (if day=1), but this is more of business logic rather then presentation. Tested this in a custom template tag def render(self, context): result = self.model._default_manager.filter(from_date__lte=self.now).filter(to_date__gte=self.now) if self.day == 4: result = result.exclude(type__exact=2).order_by('time') else: result = result.order_by('type') result[0].time = '23:23:23' context[self.varname] = result return '' However it still displays the results from the DB, is this some how related to 'lazy' evaluation of templates? Thanks! Update Responding to comments below: It's not stored wrong in the DB, its stored Correctly However there is a small side case where the value needs to change. So for example I have a From Date & To date, my query checks if todays date is between those. Now with this they could setup a from date - to date for an entire year, and the special cases (like mondays as an example) is taken care off. However if you want to store in the DB you would have to capture several more records to cater for the side case. I.e you would be capturing the same information just to cater for that 1 day when the time changes. (And the time always changes on the same day, and is always the same)

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  • Fastest XML parser for small, simple documents in Java

    - by Varkhan
    I have to objectify very simple and small XML documents (less than 1k, and it's almost SGML: no namespaces, plain UTF-8, you name it...), read from a stream, in Java. I am using JAXP to process the data from my stream into a Document object. I have tried Xerces, it's way too big and slow... I am using Dom4j, but I am still spending way too much time in org.dom4j.io.SAXReader. Does anybody out there have any suggestion on a faster, more efficient implementation, keeping in mind I have very tough CPU and memory constraints? [Edit 1] Keep in mind that my documents are very small, so the overhead of staring the parser can be important. For instance I am spending as much time in org.xml.sax.helpers.XMLReaderFactory.createXMLReader as in org.dom4j.io.SAXReader.read [Edit 2] The result has to be in Dom format, as I pass the document to decision tools that do arbitrary processing on it, like switching code based on the value of arbitrary XPaths, but also extracting lists of values packed as children of a predefined node. [Edit 3] In any case I eventually need to load/parse the complete document, since all the information it contains is going to be used at some point. (This question is related to, but different from, http://stackoverflow.com/questions/373833/best-xml-parser-for-java )

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  • Database structure for ecommerce site

    - by imanc
    Hey Guys, I have been tasked with designing an ecommerce solution. The aspect that is causing me the most problems is the database. Currently the site consists of 10+ country based shops each with their own database (all residing on the same mysql instance). For the new site I'd rather all these shop databases be merged into one database so that all tables (products, orders, customers etc.) have a shop_id field. From a programming perspective this seems to make the most sense as we won't have to manage data across multiple databases. Currently the entire site generates about 120k orders a year, but is experiencing fairly heavy growth and we need to design a solution that will scale. In 5 years there may be more than a million orders per year and a database that contains 5 years order history (archiving maybe a solution here). The question is - do we use a single database, or do we keep the database-per-shop structure? I am currently trying to find supporting evidence for either avenue. The company I am designing the solution for prefer the per-shop database structure because they believe it will allow the sites to scale. But my argument is that the shop's database probably won't get that busy over the next few years that they exceed the capacity of a mysql database and a "no expenses spared" hardware set-up. I am wondering if anyone has any advice either way? Does anyone have experience with websites / ecommerce sites that have tables containing millions of records? I know there is probably not a clear answer here, but at what stage do we have too many records or too large table files to have a fast loading site? Also, if anyone has any advice on sources of information - books, websites, etc. where I can do further research, it would be highly appreciated! Cheers, imanc

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  • IE 7 activex object (or xmlhttprequest?) open method using POST takes 20-30 seconds to return

    - by Toddeman
    i have a problem that only shows itself in IE7. its a simple ajax call. i got my object (accounting for the browser) so in 7 i SHOULD have an ActiveXObject. when i call open with POST, it takes 20-30 seconds to return. i am using a TON of GET calls to populate information and all of these work (finally, after some bug fixing), but i am NOT a web developer so much like the other bugs i had to fix, i figured i was just missing another IE anomaly. this is not a consistent bug either, which makes it harder to find for me. most times the POST functions like it does in Firefox or Chrome, but maybe 1 out of 4 or 5 will take 20-30 seconds to return. it DOES return correctly when it returns, it just takes a long time. am i missing something simple? or is there a smarter way for me to find out exactly what is going on (like the equivalent of the firebug 'net' tab for windows?).

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  • Low Level Console Input

    - by Soulseekah
    I'm trying to send commands to to the input of a cmd.exe application using the low level read/write console functions. I have no trouble reading the text (scraping) using the ReadConsole...() and WriteConsole() functions after having attached to the process console, but I've not figured out how to write for example "dir" and have the console interpret it as a sent command. Here's a bit of my code: CreateProcess(NULL, "cmd.exe", NULL, NULL, FALSE, CREATE_NEW_CONSOLE, NULL, NULL, &si, &pi); AttachConsole(pi.dwProcessId); strcpy(buffer, "dir"); WriteConsole(GetStdHandle(STD_INPUT_HANDLE), buffer, strlen(buffer), &charRead, NULL); STARTUPINFO attributes of the process are all set to zero, except, of course, the .cb attribute. Nothing changes on the screen, however I'm getting an Error 6: Invalid Handle returned from WriteConsole to STD_INPUT_HANDLE. If I write to (STD_OUTPUT_HANDLE) I do get my dir written on the screen, but nothing of course happens. I'm guessing SetConsoleMode() might be of help, but I've tried many mode combinations, nothing helped. I've also created a quick console application that waits for input (scanf()) and echoes back whatever goes in, didn't work. I've also tried typing into the scanf() promp and then peek into the input buffer using PeekConsoleInput(), returns 0, but the INPUT_RECORD array is empty. I'm aware that there is another way around this using WriteConsoleInput() to directly inject INPUT_RECORD structured events into the console, but this would be way too long, I'll have to send each keypress into it. I hope the question is clear. Please let me know if you need any further information. Thanks for your help.

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  • Open a dialog box in same window on selectOneMenu change

    - by Pravingate
    I have a jsf page where I have a selectOneMenu and , I want to open a dialog box on selectOneMenu changes. As a example if user selects a value ="passive" from jsf selectOneMenu it should open a dialog box or a light box on same page where I want to display a small jsf form like as here done. http://www.primefaces.org/showcase-labs/ui/dialogLogin.jsf and I also want save that submitted data in my backing bean somewhere so I can store it in to database later. I dont know how to open a dialog box or light box from backing bean in same window,as we will identify value change using valueChangeListener event or by using ajax event. I am able to identify which value is selected from selectOneMenu(DropdownMenu), but dont know how to open a dialog box on selecting particular value. <h:outputLabel value="* Country: "/> <h:selectOneMenu id="someSelect" value="#{testController.countryName}" required="true"> <f:selectItem itemLabel="Select Country" itemValue=""/> <f:selectItems value="#{testController.countryNamesSelectItems}"/> </h:selectOneMenu> Supoose we have 2 options in selectItems as India and Austrlia, then If a user choose India a dialog box should open on same page where a user need to fill some information and need to submit if he is from india (like here in example http://www.primefaces.org/showcase-labs/ui/dialogLogin.jsf user will put his username and password and submits data) Hope this helps How can I achieve that by using jsf or javascript or ajax or by any else way?

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  • WCF: Exposed Object Model - stuck in a loop

    - by Mark
    Hi I'm working on a pretty big WSSF project. I have a normal object model in the business layer. Eg a customer has an orders collection property, when this is accessed then it loads from the data layer (lazy loading). An order has a productCollection property etc etc.. Now the bit I'm finding tricky is exposing this via WCF. I want to export a collection of orders. The client app will also need information about the customers. Using the WSSF data contract designer I have set it up so that customers have a property called "order collection". This is fine if you have a customer object and would like to look at the orders but if you have an order object there is no customer property so it doesn't work going up the hierarchy. I've tried adding a customer property to the orders object but then the code gets stuck in a loop when it loads the data contracts up. This is because it doesn't load on demand like in the business layer. I need to load all properties up before the objects can be sent out via WCF. It ends up loading an order, then the customer for that order, then the orders for that customer, then the customer for that order etc etc... I'm sure I've got all this wrong. Help!!

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  • What database strategy to choose for a large web application

    - by Snoopy
    I have to rewrite a large database application, running on 32 servers. The hardware is up to date, each machine has two quad core Xeon and 32 GByte RAM. The database is multi-tenant, each customer has his own file, around 5 to 10 GByte each. I run around 50 databases on this hardware. The app is open to the web, so I have no control on the load. There are no really complex queries, so SQL is not required if there is a better solution. The databases get updated via FTP every day at midnight. The database is read-only. C# is my favourite language and I want to use ASP.NET MVC. I thought about the following options: Use two big SQL servers running SQL Server 2012 to serve the 32 servers with data. On the 32 servers running IIS hosting providing REST services. Denormalize the database and use Redis on each webserver. Use booksleeve as a Redis client. Use a combination of SQL Server and Redis Use SQL Server 2012 together with Hadoop Use Hadoop without SQL Server What is the best way for a read-only database, to get the best performance without loosing maintainability? Does Map-Reduce make sense at all in such a scenario? The reason for the rewrite is, the old app written in C++ with ISAM technology is too slow, the interfaces are old fashioned and not nice to use from an website, especially when using ajax. The app uses a relational datamodel with many tables, but it is possible to write one accerlerator table where all queries can be performed on, and all other information from the other tables are possible by a simple key lookup.

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  • Python Interactive Interpreter always returns "Invalid syntax" on Windows

    - by user559217
    I've encountered an extremely confusing problem. Whatever I type into the Python interpreter returns "Invalid Syntax". See examples below. I've tried fooling around with the code page of the prompt I run the interpreter from, but it doesn't seem to help at all. Furthermore, I haven't been able to find this particular, weird bug elsewhere online. Any assistance anyone could provide would be lovely. I've already tried reinstalling Python, but I didn't have any luck - the problem is also there in both 3.13 and 2.7. Running: Python version 3.1.3, Windows XP SP3. Getting: C:\Program Files\Python31>.\python Python 3.1.3 (r313:86834, Nov 27 2010, 18:30:53) [MSC v.1500 32 bit (Intel)] on win32 Type "help", "copyright", "credits" or "license" for more information. >>> 2+2 File "<stdin>", line 1 2+2 ^ SyntaxError: invalid syntax >>> x = "Oh, fiddlesticks." File "<stdin>", line 1 x = "Oh, fiddlesticks." ^ SyntaxError: invalid syntax

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  • Excel 2007 UDF keeps failing, why?

    - by Zan
    I've been trying to browse info about this for a while now. The user defined functions in Excel 2007 just make no sense to me whatsoever. According to all the tutorials, it should be really simple. Just press alt + f11, insert a new module, and enter the VBA code there. At this point typing '=FUNCTIONNAME(parameters)' into any cell should make it work. It did, at first. Then upon closing and reopening the worksheet it stopped working. I checked to see that macros were enabled, but either way, that didn't help. Then I browsed the graphic UI from the function button to locate user defined functions. I found it there by name of 'MyExcelWorksheet.xls!FUNCTIONNAME.FUNCTIONNAME' and clicking that, it started working again. Now, a day later, I get back to working on this and it's broken, again. I just get #NAME? error or some "Function Arguments - Function doesn't use any arguments" -popup (translated from Finnish Excel, not sure what that msg is in English) when I select the function from the GUI. So what does it take to just create a function, and actually make it work and KEEP working? For the life of me I can't figure out why this has to be so difficult. :) I'm starting to think my company has some weird settings enabled or whatever, because judging by the lack of information I've found on the subject, this isn't supposed to happen.

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  • Some questions about special operators i've never seen in C++ code.

    - by toto
    I have downloaded the Phoenix SDK June 2008 (Tools for compilers) and when I'm reading the code of the Hello sample, I really feel lost. public ref class Hello { //-------------------------------------------------------------------------- // // Description: // // Class Variables. // // Remarks: // // A normal compiler would have more flexible means for holding // on to all this information, but in our case it's simplest (if // somewhat inelegant) if we just keep references to all the // structures we'll need to access as classstatic variables. // //-------------------------------------------------------------------------- static Phx::ModuleUnit ^ module; static Phx::Targets::Runtimes::Runtime ^ runtime; static Phx::Targets::Architectures::Architecture ^ architecture; static Phx::Lifetime ^ lifetime; static Phx::Types::Table ^ typeTable; static Phx::Symbols::Table ^ symbolTable; static Phx::Phases::PhaseConfiguration ^ phaseConfiguration; 2 Questions : What's that ref keyword? What is that sign ^ ? What is it doing protected: virtual void Execute ( Phx::Unit ^ unit ) override; }; override is a C++ keyword too? It's colored as such in my Visual Studio. I really want to play with this framework, but this advanced C++ is really an obstacle right now. Thank you.

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  • How to debug a Gruntfile with breakpoints using node-inspector?

    - by Kris Hollenbeck
    So I have spent the past couple days trying to get this to work with no luck. Most of the solutions I have found seem to work "okay" for debugging node applications. But I haven't had much luck debugging grunt stand alone. I would like to be able to set breakpoints in my gruntfile and either step through the code with either the browser or an IDE. I have tried the following: Debugging using intelliJ IDE Using Grunt Console (Process finished with exit code 6) Debugging with Nodeeclipse (This sort of works okay but doesn't hit the breakpoints set in eclipse, not very intuitive) Debugging using node-inspector (This one also sort of works. I can step through a little ways using F11 and F10 in chrome. But eventually it just crashes. Using F8 to skip to break point never works.) ERROR MESSAGE USING NODE-INSPECTOR So currently node-inspector feels like it has gotten me the closest to what I want. To get here I did the following: From my grunt directory I ran the following commands: grunt node-inspector node --debug-brk Gruntfile.js And then from there I went to localhost:8080/debug?port=5858 to debug my Gruntfile.js. But like I mentioned above, as soon as I hit F8 to skip to breakpoint it crashes with the above error. Has anybody had any success using this method to try to debug a Gruntfile? So far from my search efforts I have not found a very well documented way of doing this. So hopefully this will be useful or beneficial information for future users. Also I am using Windows 7 by the way. Thanks in advance.

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  • Testing a method used from an abstract class

    - by Bas
    I have to Unit Test a method (runMethod()) that uses a method from an inhereted abstract class to create a boolean. The method in the abstract class uses XmlDocuments and nodes to retrieve information. The code looks somewhat like this (and this is extremely simplified, but it states my problem) namespace AbstractTestExample { public abstract class AbstractExample { public string propertyValues; protected XmlNode propertyValuesXML; protected string getProperty(string propertyName) { XmlDocument doc = new XmlDocument(); doc.Load(new System.IO.StringReader(propertyValues)); propertyValuesXML= doc.FirstChild; XmlNode node = propertyValuesXML.SelectSingleNode(String.Format("property[name='{0}']/value", propertyName)); return node.InnerText; } } public class AbstractInheret : AbstractExample { public void runMethod() { bool addIfContains = (getProperty("AddIfContains") == null || getProperty("AddIfContains") == "True"); //Do something with boolean } } } So, the code wants to get a property from a created XmlDocument and uses it to form the result to a boolean. Now my question is, what is the best solution to make sure I have control over the booleans result behaviour. I'm using Moq for possible mocking. I know this code example is probably a bit fuzzy, but it's the best I could show. Hope you guys can help.

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  • Merge computed data from two tables back into one of them

    - by Tyler McHenry
    I have the following situation (as a reduced example). Two tables, Measures1 and Measures2, each of which store an ID, a Weight in grams, and optionally a Volume in fluid onces. (In reality, Measures1 has a good deal of other data that is irrelevant here) Contents of Measures1: +----+----------+--------+ | ID | Weight | Volume | +----+----------+--------+ | 1 | 100.0000 | NULL | | 2 | 200.0000 | NULL | | 3 | 150.0000 | NULL | | 4 | 325.0000 | NULL | +----+----------+--------+ Contents of Measures2: +----+----------+----------+ | ID | Weight | Volume | +----+----------+----------+ | 1 | 75.0000 | 10.0000 | | 2 | 400.0000 | 64.0000 | | 3 | 100.0000 | 22.0000 | | 4 | 500.0000 | 100.0000 | +----+----------+----------+ These tables describe equivalent weights and volumes of a substance. E.g. 10 fluid ounces of substance 1 weighs 75 grams. The IDs are related: ID 1 in Measures1 is the same substance as ID 1 in Measures2. What I want to do is fill in the NULL volumes in Measures1 using the information in Measures2, but keeping the weights from Measures1 (then, ultimately, I can drop the Measures2 table, as it will be redundant). For the sake of simplicity, assume that all volumes in Measures1 are NULL and all volumes in Measures2 are not. I can compute the volumes I want to fill in with the following query: SELECT Measures1.ID, Measures1.Weight, (Measures2.Volume * (Measures1.Weight / Measures2.Weight)) AS DesiredVolume FROM Measures1 JOIN Measures2 ON Measures1.ID = Measures2.ID; Producing: +----+----------+-----------------+ | ID | Weight | DesiredVolume | +----+----------+-----------------+ | 4 | 325.0000 | 65.000000000000 | | 3 | 150.0000 | 33.000000000000 | | 2 | 200.0000 | 32.000000000000 | | 1 | 100.0000 | 13.333333333333 | +----+----------+-----------------+ But I am at a loss for how to actually insert these computed values into the Measures1 table. Preferably, I would like to be able to do it with a single query, rather than writing a script or stored procedure that iterates through every ID in Measures1. But even then I am worried that this might not be possible because the MySQL documentation says that you can't use a table in an UPDATE query and a SELECT subquery at the same time, and I think any solution would need to do that. I know that one workaround might be to create a new table with the results of the above query (also selecting all of the other non-Volume fields in Measures1) and then drop both tables and replace Measures1 with the newly-created table, but I was wondering if there was any better way to do it that I am missing.

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  • Debug formatting code

    - by Arcadian
    I'm trying to debug my code here: private void CheckFormatting() { StringReader objReaderf = new StringReader(txtInput.Text); List<String> formatTextList = new List<String>(); do { formatTextList.Add(objReaderf.ReadLine()); } while (objReaderf.Peek() != -1); objReaderf.Close(); for (int i = 0; i < formatTextList.Count; i++) { if (!Regex.IsMatch(formatTextList[i], "G[0-9]{2}:[0-9]{2}:[0-9]{2}:[0-9]{2} JG[0-9]{2")) { MessageBox.Show("Line " + formatTextList[i] + " is not formatted correctly.", "Error", MessageBoxButtons.OK, MessageBoxIcon.Error); break; } else { this.WriteToFile(); MessageBox.Show("Your entries have been saved.", "Saved", MessageBoxButtons.OK, MessageBoxIcon.Information); } } } what it is supposed to do is to check each line in the list. if one of them isn't formatted correctly, then break the loop and display a message box, if all the lines are formatted properly then it should call the WriteToFile method. However, when testing it using input that WAS correctly formatted it displayed the error message and broke the loop. Anyone figure out why? There's some rep points in it for you :) Thanks in advance

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  • object / class methods serialized as well?

    - by Mat90
    I know that data members are saved to disk but I was wondering whether object's/class' methods are saved in binary format as well? Because I found some contradictionary info, for example: Ivor Horton: "Class objects contain function members as well as data members, and all the members, both data and functions, have access specifiers; therefore, to record objects in an external file, the information written to the file must contain complete specifications of all the class structures involved." and: Are methods also serialized along with the data members in .NET? Thus: are method's assembly instructions (opcodes and operands) stored to disk as well? Just like a precompiled LIB or DLL? During the DOS ages I used assembly so now and then. As far as I remember from Delphi and the following site (answer by dan04): Are methods also serialized along with the data members in .NET? sizeof(<OBJECT or CLASS>) will give the size of all data members together (no methods/procedures). Also a nice C example is given there with data and members declared in one class/struct but at runtime these methods are separate procedures acting on a struct of data. However, I think that later class/object implementations like Pascal's VMT may be different in memory.

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  • LINQ Joins - Performance

    - by Meiscooldude
    I am curious on how exactly LINQ (not LINQ to SQL) is performing is joins behind the scenes in relation to how Sql Server performs joins. Sql Server before executing a query, generates an Execution Plan. The Execution Plan is basically an Expression Tree on what it believes is the best way to execute the query. Each node provides information on whether to do a Sort, Scan, Select, Join, ect. On a 'Join' node in our execution plan, we can see three possible algorithms; Hash Join, Merge Join, and Nested Loops Join. Sql Server will choose which algorithm to for each Join operation based on expected number of rows in Inner and Outer tables, what type of join we are doing (some algorithms don't support all types of joins), whether we need data ordered, and probably many other factors. Join Algorithms: Nested Loop Join: Best for small inputs, can be optimized with ordered inner table. Merge Join: Best for medium to large inputs sorted inputs, or an output that needs to be ordered. Hash Join: Best for medium to large inputs, can be parallelized to scale linearly. LINQ Query: DataTable firstTable, secondTable; ... var rows = from firstRow in firstTable.AsEnumerable () join secondRow in secondTable.AsEnumerable () on firstRow.Field<object> (randomObject.Property) equals secondRow.Field<object> (randomObject.Property) select new {firstRow, secondRow}; SQL Query: SELECT * FROM firstTable fT INNER JOIN secondTable sT ON fT.Property = sT.Property Sql Server might use a Nested Loop Join if it knows there are a small number of rows from each table, a merge join if it knows one of the tables has an index, and Hash join if it knows there are a lot of rows on either table and neither has an index. Does Linq choose its algorithm for joins? or does it always use one?

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  • MVC 3, View Model for user registration process. Password validation not working properly

    - by sec_goat
    I am trying to create a user registration page using MVC 3, so that I can better understand the process of how it works, what's going on behind the scenes etc. I am running into some issues when trying to use [Compare] to check to see that the user entered the same password twice. I tried adding the ComparePassword field to my user model first, and found that would not work the way I wanted as I did not have the field in the database, so the obvious answer was to create a View Model using the same information including the ComparePassword field. So I now have created a User model and a RegistrationViewModel, however it appears that the [Compare] on the password is not returning anything, for instance no matter what I put in the two boxes, when I click create it gives no error, which seems to me to mean it was successfully validated. I am not sure what I am doing or not doing to make this work properly. I have tried updating the jQuery.Validate to the newest version as there were some bugs reported in older version, this has not helped my efforts. Below is a wall of code, that is what I am working with. } public class RegistrationViewModel { [Required] [StringLength(15, MinimumLength = 3)] [Display(Name = "User Name")] [RegularExpression(@"(\S)+", ErrorMessage = " White Space is not allowed in User Names")] [ScaffoldColumn(false)] public String Username { get; set; } [Required] [StringLength(15, MinimumLength = 3)] [Display(Name = "First Name")] public String firstName { get; set; } [Required] [StringLength(15, MinimumLength = 3)] [Display(Name = "Last Name")] public String lastName { get; set; } [Required] [Display(Name = "Email")] public String email { get; set; } [Required] [Display(Name = "Password")] [DataType(DataType.Password)] public String password { get; set; } [Required] [DataType(DataType.Password)] [Display(Name = "Re-enter Password")] [Compare("Password", ErrorMessage = "Passwords do not match.")] public String comparePassword { get; set; } }

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  • Error accessing uncompiled pages using ISA Server 2006 SP1

    - by Bravax
    We are in the processing of configuring a portal to use ISA Server as our front end security provider. So we are using ISA Server 2006 SP1. Unfortunately when we access .net applications through ISA Server, the first time they are accessed. i.e. They are not compiled yet, the following error appears: Error Code: 500 Internal Server Error. The parameter is incorrect. (87) In the ISA Monitoring logs, this shows: Failed Connection Attempt Log type: Web Proxy (Reverse) Status: 87 The parameter is incorrect. Once the application is compiled, the error never appears. Does anyone know how to resolve this, so the site works correctly the first time? Some additional information: The websites accessed are running on windows server 2008 64 bit - standard edition, and occurs for Sharepoint as well as standard .net websites. ISA Server is running on Windows server 2003 R2 SP2 Standard eidtion The firewall on the windows server 2008 box allows all access. (To rule this out.) Nothing odd appears in the IIS logs or firewall logs.

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  • What Getters and Setters should and shouldn't do.

    - by cyclotis04
    I've run into a lot of differing opinions on Getters and Setters lately, so I figured I should make it into it's own question. A previous question of mine received an immediate comment (later deleted) that stated setters shouldn't have any side effects, and a SetProperty method would be a better choice. Indeed, this seems to be Microsoft's opinion as well. However, their properties often raise events, such as Resized when a form's Width or Height property is set. OwenP also states "you shouldn't let a property throw exceptions, properties shouldn't have side effects, order shouldn't matter, and properties should return relatively quickly." Yet Michael Stum states that exceptions should be thrown while validating data within a setter. If your setter doesn't throw an exception, how could you effectively validate data, as so many of the answers to this question suggest? What about when you need to raise an event, like nearly all of Microsoft's Control's do? Aren't you then at the mercy of whomever subscribed to your event? If their handler performs a massive amount of information, or throws an error itself, what happens to your setter? Finally, what about lazy loading within the getter? This too could violate the previous guidelines. What is acceptable to place in a getter or setter, and what should be kept in only accessor methods?

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  • RTTI Dynamic array TValue Delphi 2010

    - by user558126
    Hello I have a question. I am a newbie with Run Time Type Information from Delphi 2010. I need to set length to a dynamic array into a TValue. You can see the code. Type TMyArray = array of integer; TMyClass = class publihed function Do:TMyArray; end; function TMyClass.Do:TMyArray; begin SetLength(Result,5); for i:=0 to 4 Result[i]=3; end; ....... ....... ...... y:TValue; Param:array of TValue; ......... y=Methods[i].Invoke(Obj,Param);//delphi give me a DynArray type kind, is working, Param works to any functions. if Method[i].ReturnType.TypeKind = tkDynArray then//is working... begin I want to set length for y to 10000//i don't know how to write. end; I don't like Generics Collections.

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  • Passing a WHERE clause for a Linq-to-Sql query as a parameter

    - by Mantorok
    Hi all This is probably pushing the boundaries of Linq-to-Sql a bit but given how versatile it has been so far I thought I'd ask. I have 3 queries that are selecting identical information and only differ in the where clause, now I know I can pass a delegate in but this only allows me to filter the results already returned, but I want to build up the query via parameter to ensure efficiency. Here is the query: from row in DataContext.PublishedEvents join link in DataContext.PublishedEvent_EventDateTimes on row.guid equals link.container join time in DataContext.EventDateTimes on link.item equals time.guid where row.ApprovalStatus == "Approved" && row.EventType == "Event" && time.StartDate <= DateTime.Now.Date.AddDays(1) && (!time.EndDate.HasValue || time.EndDate.Value >= DateTime.Now.Date.AddDays(1)) orderby time.StartDate select new EventDetails { Title = row.EventName, Description = TrimDescription(row.Description) }; The code I want to apply via a parameter would be: time.StartDate <= DateTime.Now.Date.AddDays(1) && (!time.EndDate.HasValue || time.EndDate.Value >= DateTime.Now.Date.AddDays(1)) Is this possible? I don't think it is but thought I'd check out first. Thanks

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