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  • How to use bll, dal and model?

    - by bruno
    Dear all, In my company I must use a Bll, Dal and model layer for creating applications with a database. I've learned at school that every databasetable should be an object in my model. so I create the whole model of my database. Also I've learned that for every table (or model object) there should be a DAO created into the DAL. So I do this to. Now i'm stuck with the BLL classes. I can write a BLLclass for each DAO/ModelObject or I can write a BLLclass that combine some (logic) DAO's... Or i can write just one Bllclass that will manage everything. (this last one I'm sure it aint the best way..) What is the best practice to handle this Bll 'problem'? And a second question. If a bll is in need of tablecontent from an other table where it aint responsible for, whats the best way to get the content? Go ask on the responsible BLL or go directly to the DAO? I'm struggling with these questions the last 2 months, and i don't know what is the best way to handle it.

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  • WPF - Setting ComboBox.SelectedItem in XAML based on matching object

    - by Andy T
    Hi, so, I have templated combobox that is basically acting as a simple colour palette. It is populated with a list of SolidColorBrush objects. Fine. Now, I have some data that holds the hex value of the current colour. I have a converter that converts the hex into a SolidColorBrush. Also fine. Now, I want to set the SelectedItem property of the combobox based on the colour from my datasource. Since my combo is populated with objects of type SolidColourBrush, and my binding converter is returning a SolidColorBrush, I assumed it would be as simple as saying: SelectedItem="{Binding Color, Converter={StaticResource StringToBrush}}" However... it doesn't work :( I've tested that the binding is working behind the scenes by using the exact same value for the Background property of the combobox. It works fine. So, clearly I can't just say SelectedItem = [something] where that [something] is basically an object equal to the item I want to be selected. What is the right way to do this? Surely it's possible in a XAML-only styley using binding, and I don't have to do some nasty C# iterating through all items in the combobox trying to find a match (that seems awfully old-school)...? Any help appreciated. Many thanks! AT

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  • what data structure should I use for hash lookup as well as binary search?

    - by zebraman
    I am working on a school homework. I have a list of names. I want to be able to perform binary search on these names (find all names between a lower and upper bound) for first name as well as last name, and perform keyword searches as well (this will be accomplished using hashing. For example, if I have the names Garfield Cat Snoopy Dog Captain Crunch Fat Cat then a binary search of first names (C,H) will return Captain Crunch, Fat Cat, and Garfield Cat. A binary search of last names (Cr,D) will return Captain Crunch. A keyword search of 'cat' will return Fat Cat and Garfield Cat. I understand binary search will only work on a sorted list, but since I am planning on searching two different criteria, I will have to sort the list by last name or first name depending on what I'm searching for. I feel like it will be too inefficient to have to resort the list each time I want to perform a new binary search. Would it just be better for me to set up and maintain two sorted lists (one for sorted by first name, one for sorted by last name)? Also, for hashing, will I have to set up a different table of names for that as well? I understand each keyword will hash to some value determined by a hash function, and this value (or key) is a table address where the corresponding names are stored. So I just want to know what would be the best way to solve this problem? Maintaining separate structures, or is there a way to efficiently do everything I want with just one data structure?

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  • Object not declared in scope

    - by jay
    I'm using Xcode for C++ on my computer while using Visual Studio at school. The following code worked just fine in Visual Studio, but I'm having this problem when using Xcode. clock c1(2, 3, 30); Everything works just fine, but it keeps giving me this error that says "Expected ';' before 'c1'" Fine, I put the ';' .. but then, it gives me this error: "'c1' was not declared in this scope" Here's the whole header code: #include <iostream> using namespace std; class clock { private: int h; int m; int s; public: clock(int hr, int mn, int sec); }; clock::clock(int hr, int mn, int sec) { h = hr; m = mn; s = sec; } Here's the whole .cpp code: #include "clock.h" int main() { clock c1(2, 3, 30); return 0; } I stripped everything down to where I had the problem. Everything else, as far as I know, is irrelevant since the problem remains the same with just the mentioned above. Thanks in advance!

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  • sql exception when transferring project from usb to c:\

    - by jello
    I'm working on a C# windows program with Visual Studio 2008. Usually, I work from school, directly on my usb drive. But when I copy the folder on my hard drive at home, an sql exception is unhandled whenever I try to write to the database. it is unhandled at the conn.Open(); line. here's the exception unhandled Database 'L:\system\project\the_project\the_project\bin\Debug\PatientMonitoringDatabase.mdf' already exists. Choose a different database name. Cannot attach the file 'C:\Documents and Settings\Administrator\My Documents\system\project\the_project\the_project\bin\Debug\PatientMonitoringDatabase.mdf' as database 'PatientMonitoringDatabase'. it's weird, because my connection string says |DataDirectory|, so it should work on any drive... here's my connection string: string connStr = "Data Source=.\\SQLEXPRESS;AttachDbFilename=|DataDirectory|\\PatientMonitoringDatabase.mdf; " + "Initial Catalog=PatientMonitoringDatabase; " + "Integrated Security=True"; Someone told me to: Connect to localhost with SQL Server Management Studio Express, and remove/detach the existing PatientMonitoringDatabase database. Whether it's a persistent database or only active within a running application, you can't have 2 databases with the same name at the same time attached to a SQL Server instance. So I did that, and now it gives me: Directory lookup for the file "C:\Documents and Settings\Administrator\My Documents\system\project\the_project\the_project\bin\Debug\PatientMonitoringDatabase.mdf" failed with the operating system error 5(Access is denied.). Cannot attach the file 'C:\Documents and Settings\Administrator\My Documents\system\project\the_project\the_project\bin\Debug\PatientMonitoringDatabase.mdf' as database 'PatientMonitoringDatabase' I checked the files' properties, and I have allow for everyone. Does anyone know what's going on here?

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  • Which Javascript framework (jQuery vs Dojo vs ... )?

    - by cletus
    There are a few Javascript frameworks/toolets out there, such as: jQuery; Dojo; Prototype; YUI; MooTools; ExtJS; SmartClient; and others I'm sure. It certainly seems that jQuery is ascendant in terms of mindshare at the moment. For example, Microsoft (ASP.NET MVC) and Nokia will use it. I also found this this performance comparison of Dojo, jQuery, MooTools and Prototype (Edit: Updated Comparison), which looks highly favourable to Dojo and jQuery. Now my previous experience with Javascript has been the old school HTML + Javascript most of us have done and RIA frameworks like Google Web Toolkit ("GWT") and Ext-GWT, which were a fairly low-stress entry into the Ajax world for someone from a Java background, such as myself. But, after all this, I find myself leaning towards the more PHP + Ajax type solution, which just seems that much more lightweight. So I've been looking into jQuery and I really like it's use of commands, the use of fluent interfaces and method chaining, it's cross-browser CSS selector superset, the fact that it's lightweight and extensible, the brevity of the syntax, unobtrusive Javascript and the plug-in framework. Now obviously many of these aren't unique to jQuery but on the basis that some things are greater than their sum of parts, it just seems that it all fits together and works well. So jQuery seems to have a lot going for it and it looks to the frontrunner for what I choose to concentrate on. Is there anything else I should be aware of or any particular reasons not to choose it or to choose something else? EDIT: Just wanted to add this trend comparison of Javascript frameworks.

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  • A problem with connected points and determining geometry figures based on points' location analysis

    - by StolePopov
    In school we have a really hard problem, and still no one from the students has solved it yet. Take a look at the picture below: http://d.imagehost.org/0422/mreza.gif That's a kind of a network of connected points, which doesn't end and each point has its own number representing it. Let say the numbers are like this: 1-23-456-78910-etc. etc.. (You can't see the number 5 or 8,9... on the picture but they are there and their position is obvious, the point in middle of 4 and 6 is 5 and so on). 1 is connected to 2 and 3, 2 is connected to 1,3,5 and 4 etc. The numbers 1-2-3 indicate they represent a triangle on the picture, but the numbers 1-4-6 do not because 4 is not directly connected with 6. Let's look at 2-3-4-5, that's a parallelogram (you know why), but 4-6-7-9 is NOT a parallelogram because the in this problem there's a rule which says all the sides must be equal for all the figures - triangles and parallelograms. Also there are hexagons, for ex. 4-5-7-9-13-12 is a hexagon - all sides must be equal here too. 12345 - that doesn't represent anything, so we ignore it. I think i explained the problem well. The actual problem which is given to us by using an input of numbers like above to determine if that's a triangle/parallelogram/hexagon(according to the described rules). For ex: 1 2 3 - triangle 11 13 24 26 -parallelogram 1 2 3 4 5 - nothing 11 23 13 25 - nothing 3 2 5 - triangle I was reading computational geometry in order to solve this, but i gave up quickly, nothing seems to help here. One friend told me this site so i decided to give it a try. If you have any ideas about how to solve this, please reply, you can use pseudo code or c++ whatever. Thank you very much.

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  • IBM Informix Spatial datablade LIneFromText function

    - by swatit
    Hi Everybody, I am using IBM-Informix for my school project as part of "Informix on-campus" ativity conduted by IBM. I am using spatial datablade to store spatial data. My spatial data table looks like, CREATE TABLE xmlTest (row_id integer NOT NULL,pre integer, post integer,parent integer,tagname varchar(40,1),point ST_POINT); Then I inserted the spatial data into the table. Now I am trying to select the 'Points' lying under given 'polygon', where the co-ordinates of the polygon are dynamic i.e co-ordinates will be decided in the 'select' query. My query is like SELECT v2.* FROM xmlTest v1,xmlTest v2 WHERE ST_Contains(ST_Polygon(ST_LineFromText('linestring (0 0, 22000 0,22000 22000,0 22000,0 0)',5)),ST_Point(v1.pre,v1.post,5)) AND v1.tagname like 'n1' AND ST_Contains(ST_Polygon(ST_LineFromText('linestring (0 0,v1.pre 0,v1.pre v1.post,0 v1.post,0 0 )',5)),ST_Point(v2.pre,v2.post,5)) AND v2.tagname like 'n2' however it is giving me error as "(USE31) - Too few points for geometry type in ST_LineFromText.", in the second linefromtext function. I checked the number of parameters for linestring function, but could not find the source of error. I think,linestring function's parameters should be fixed values and not the variable like in this query. Is it right? Then what is the alternate way, where I can specify my polygon co-ordinates dynamically? or is there any mistake in my query? I hope my question is clear. I appreciate your help!

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  • WCF Data Services - neither .Expand or .LoadProperty seems to do what I need

    - by TomK
    I am building a school management app where they track student tardiness and absences. I've got three entities to help me in this. A Students entity (first name, last name, ID, etc.); a SystemAbsenceTypes entity with SystemAbsenceTypeID values for Late, Absent-with-Reason, Absent-without-Reason; and a cross-reference table called StudentAbsences (matching the student IDs with the absence-type ID, plus a date, and a Notes field). What I want to do is query my entities for a given student, and then add up the number of each kind of Absence, for a given date range. I prepare my currentStudent object without a problem, then I do this... Me.Data.LoadProperty(currentStudent, "StudentAbsences") 'Loads the cross-ref data lblDaysLate.Text = (From ab In currentStudent.StudentAbsences Where ab.SystemAbsenceTypes.SystemAbsenceTypeID = Common.enuStudentAbsenceTypes.Late).Count.ToString ...and this second line fails, complaining it has no value for an object. I presume the problem is that while it DOES see that there are (let's say) four absences for the currentStudent (ie, currentStudent.StudentAbsences.Count = 4) -- it can't yet "peer into" each one of the absences to look at its type. How do I use .Expand or .LoadProperty to make this happen? I tried fiddling with .LoadProperty but it doesn't take a two-level syntax like so... Data.LoadProperty(currentStudent,"StudentAbsences.SystemAbsenceTypeID") or the like. Is there some other technique?

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  • Visual C++ Assembly link library troubles

    - by Sanarothe
    Hi. I'm having a problem having my projects built in VC++ Express 2008... I'm using a library, irvine32.inc/lib. INCLUDE Irvine32.inc works for me at school (On already configured VS environments) by default, but at home (Windows 7 x64) I'm having a boatload of issues. My original post here was that a file that irvine32.inc referenced, in the same folder, 'could not be opened.' Added irvine folder to the include path for specific project, progress. Then I was getting an error with mt.exe, but a suggestion on the MSDN suggested turn off antivirus, and now project does build but when I run a program that does NOT reference anything in irvine32, it tells me repeatedly that my project has triggered a breakpoint, and allows me to continue or break. Continue just pops the same window, break loads another popup telling me that "No symbols are loaded for any call stack frame. Source code cannot be displayed." This popup lets me view the disassembly. I tested it with and without working statements, it just throws the same breakpoint on the first line of code. Now, if I run the program when it DOES require something from the include file, in this case, DumpRegs: INCLUDE Irvine32.inc .data .code main PROC mov ebx,1000h mov eax,1000h add eax,ebx call DumpRegs main ENDP END main This gives me 1main.obj : error LNK2019: unresolved external symbol _DumpRegs@0 referenced in function _main@0 1C:\Users\Cameron\csis165\Lab8_CCarroll\Debug\Lab8_CCarroll.exe : fatal error LNK1120: 1 unresolved externals This does NOT happen when I build a project from the book author's examples, which has the same include statement. I'm baffled. :(

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  • jitter if multiple outliers in ggplot2 boxplot

    - by Andreas
    I am trying to find a suitable display to illustrate various properties within and across school classes. For each class there is only 15-30 data points (pupils). Right now i am leaning towards a whisker-less boxplot, showing only 1.,2. and 3. quartile + datapoints more then e.g. 1 population SD +/- the sample median. This I can do. However - I need to show this graph to some teachers, in order to gauge what they like most. I'd like to compare my graph with a normal boxplot. But the normal boxplot looks the same if there is only one outlier, or e.g. 5 outliers at the same value. In this case this would be a deal-breaker. e.g. test <-structure(list(value = c(3, 5, 3, 3, 6, 4, 5, 4, 6, 4, 6, 4, 4, 6, 5, 3, 3, 4, 4, 4, 3, 4, 4, 4, 3, 4, 5, 6, 6, 4, 3, 5, 4, 6, 5, 6, 4, 5, 5, 3, 4, 4, 6, 4, 4, 5, 5, 3, 4, 5, 8, 8, 8, 8, 9, 6, 6, 7, 6, 9), places = structure(c(1L, 2L, 1L, 1L, 1L, 2L, 1L, 2L, 1L, 2L, 1L, 2L, 2L, 2L, 2L, 2L, 1L, 1L, 2L, 2L, 2L, 1L, 2L, 1L, 1L, 1L, 1L, 2L, 1L, 2L, 1L, 2L, 2L, 2L, 1L, 2L, 1L, 2L, 2L, 1L, 1L, 2L, 2L, 1L, 1L, 1L, 1L, 2L, 1L, 1L, 2L, 2L, 2L, 1L, 1L, 2L, 2L, 1L, 2L, 1L), .Label = c("a", "b"), class = "factor")), .Names = c("value", "places"), row.names = c(NA, -60L), class = "data.frame") ggplot(test, aes(x=places,y=value))+geom_boxplot() Here there are two outliers at ("a",9) - but only one "dot" shown. So my question: How to jitter the outliers. And - what kind of display would you suggest for this kind of data?

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  • Do programmers need a union?

    - by James A. Rosen
    In light of the acrid responses to the intellectual property clause discussed in my previous question, I have to ask: why don't we have a programmers' union? There are many issues we face as employees, and we have very little ability to organize and negotiate. Could we band together with the writers', directors', or musicians' guilds, or are our needs unique? Has anyone ever tried to start one? If so, why did it fail? (Or, alternatively, why have I never heard of it, despite its success?) later: Keith has my idea basically right. I would also imagine the union being involved in many other topics, including: legal liability for others' use/misuse of our work, especially unintended uses evaluating the quality of computer science and software engineering higher education programs -- unlike many other engineering disciplines, we are not required to be certified on receiving our Bachelor's degrees evangelism and outreach -- especially to elementary school students certification -- not doing it, but working with the companies like ISC(2) and others to make certifications meaningful and useful continuing education -- similar to previous conferences -- maintain a go-to list of organizers and other resources our members can use I would see it less so as a traditional trade union, with little emphasis on: pay -- we tend to command fairly good salaries outsourcing and free trade -- most of use tend to be pretty free-market oriented working conditions -- we're the only industry with Aeron chairs being considered anything like "standard"

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  • Mysterious extra hashtable entry

    - by Harm De Weirdt
    Good evening everyone, I'm back :) Let me explain my problem. I have a hashtable in wich I store the products a costumors buys (%orders). It uses the productcode as key and has a reference to an array with the other info as value. At the end of the program, I have to rewrite the inventory to the updated version (i.e. subtract the quantity of the bought items) This is how I do this: sub rewriteInventory{ open(FILE,'>inv.txt'); foreach $key(%inventory){ print FILE "$key\|$inventory{$key}[0]\|$inventory{$key}[1]\|$inventory{$key}[2]\n" } close(FILE); } where $inventory{$key}[x] is 0 - Title, 1 - price, 2 - quantity. The problem here is that when I look at inv.txt afterwards, I see things like this: CD-911|Lady Gaga - The Fame|15.99|21 ARRAY(0x145030c)||| BOOK-1453|The Da Vinci Code - Dan Brown|14.75|12 ARRAY(0x145bee4)||| Where do these "ARRAY(0x145030c)|||" entries come from? Or more important, how do I get rid of them? This is the last part of this school task, I had so much problems programming all this and this stupid little thing comes up now and I'm really fed up with this whole Perl thing. (this aside :p) I hope someone can help me :) Fuji

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  • Control Oracle Forms with outside program

    - by user256893
    I work at a company that uses the Forms based Oracle 11i. A lot of employees complain of the redundancy of data entry and I want to write a program that will ease some of that pain since all attempts to ask IT to do it have failed. The problem is, since Oracle Forms are Java based there are no "controls" as there would be on say a windows application or an HTML based form. Does anyone know of a way to tell the PC to (example only) click edit field 3 on the RMA creation form and then enter the data? The only way I can programmatically navigate Oracle is with hotkeys and it's very unreliable. I'm not concerned about the language or learning a new application to resolve this issue. I currently know (elementary to Intermediate levels) Java, VB.NET and will be taking C++ in school. Is there a tool, bridge, element spy of some sort that will allow me to send commands to elements on the forms? edit APC sez: Oracle Forms over the web run as a Java applet. I mention this because it may be relevant to your responses.

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  • Good Learning Method for Objective-C?

    - by Josh Kahane
    Hi I know this must be asked a millions times and can't be easy to answer as there is o definitive method, but any help would be appreciated, thanks. I have been playing around with all sorts of things in Xcode and with Objective-C, however I can't seem to find a good way of learning things in an efficient way. I have bought the book 'Programming in Objective-C 2.0' and its great but just lays down the basics it seems. I want to learn in the 2D game development direction, then of course 3D after nailing that, if thats the right thing to do? I am 17 currently in year 13, last year of school/A Levels and am almost definitely taking a gap year. Any good, well known reputable courses online or offline (real world)? This is my first programming language, and I am absolutely serious about learning this. One last question, is when learning things online, I have in the past started building a feature and learning a certain aspect in programming only to find out after adding more its slows down the app or its to inefficient. Is the key to use a certain method in a certain situation (being os many ways to do the same thing) or use any of those methods and refine it in your app to make it run smoothly? Sorry, its hard for me to know when I have little experience, thus far. Sorry for rambling on! I would appreciate any help, thank you!

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  • Bash script to log in over SSH

    - by user1042928
    Sorry if this seems like a dumb question but I am just learning bash scripting. For a school project we need to code an RTX that runs in Unix. It runs as a process in terminal and takes in user input and then prints it to the screen. I want to write a bash script to test that it can respond to lots of quick user input without overflowing or failing. My main problem is that once the RTX starts the bash script will stop on that line until the RTX terminates and only then print the loop to the terminal (instead of printing it to the RTX prompt as I intend it to). I have tried running the RTX in the background but that didn't work. I need to find a way to redirect input to the RTX while it is still running with a bash script. Google searches didn't come up with examples that I understood/could adapt. Any help is appreciated. #!/bin/bash # declare STRING variable STRING="RTX Worked =D" #Start the rtx in a new process, stuck on this line until rtx terminates. ./main #Somehow redirect io to the rtx. for i in `seq 1 100`; do echo $i echo " \n" done echo $STRING

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  • How to avoid loading a LINQ to SQL object twice when editting it on a website.

    - by emzero
    Hi guys I know you are all tired of this Linq-to-Sql questions, but I'm barely starting to use it (never used an ORM before) and I've already find some "ugly" things. I'm pretty used to ASP.NET Webforms old school developing, but I want to leave that behind and learn the new stuff (I've just started to read a ASP.NET MVC book and a .NET 3.5/4.0 one). So here's is one thing I didn't like and I couldn't find a good alternative to it. In most examples of editing a LINQ object I've seen the object is loaded (hitting the db) at first to fill the current values on the form page. Then, the user modify some fields and when the "Save" button is clicked, the object is loaded for second time and then updated. Here's a simplified example of ScottGu NerdDinner site. // // GET: /Dinners/Edit/5 [Authorize] public ActionResult Edit(int id) { Dinner dinner = dinnerRepository.GetDinner(id); return View(new DinnerFormViewModel(dinner)); } // // POST: /Dinners/Edit/5 [AcceptVerbs(HttpVerbs.Post), Authorize] public ActionResult Edit(int id, FormCollection collection) { Dinner dinner = dinnerRepository.GetDinner(id); UpdateModel(dinner); dinnerRepository.Save(); return RedirectToAction("Details", new { id=dinner.DinnerID }); } As you can see the dinner object is loaded two times for every modification. Unless I'm missing something about LINQ to SQL caching the last queried objects or something like that I don't like getting it twice when it should be retrieved only one time, modified and then comitted back to the database. So again, am I really missing something? Or is it really hitting the database twice (in the example above it won't harm, but there could be cases that getting an object or set of objects could be heavy stuff). If so, what alternative do you think is the best to avoid double-loading the object? Thank you so much, Greetings!

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  • Working for free

    - by truncate
    Finances are making me take an extended period off of my college education. In my current state, I don't feel fully qualified to be employed by an iPhone software company. While I work on getting things back together, I'd like to try an work for a software company for free in my local area (I'm going to college out of state and have to move back as well). The economy has forced employers to be very picky about who they hire, if any at all. Since I'd like to continue refining my abilities, I was wondering on what the consensus is on working for free. It can't be considered an internship, as I would no longer be in school..., I guess an apprenticeship is more appropriate. Like I said, I don't think I'm qualified to be paid for my services, and I don't want to be. I just don't know how to ask, or if it's even appropriate to ask them to show me how to develop software in the real world. My thinking is that they would be willing to get some work done for free and if I prove myself, they could hire me. If not, there was no major loss. They get some free development, and lose a bit of time helping show me the ropes. I get either a job, or valuable experience that I need. The other alternative is that I try to work out things by myself on the iPhone platform, but that sounds terrifying. I appreciate any input the community has to offer.

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  • having trouble disabling textbox in vb.net

    - by user225269
    How do I disable a textbox the second time? here is my code, In form load the textbox is disabled, unless the user will input an idnumber that is in the database. But what if the user will input an idnumber that is in the database then, input again another that is not, That is where this code comes in, but it has problems, it doesnt disable the textbox in the event of a mouse click, what would be the proper way of doing this? Private Sub Button12_MouseClick(ByVal sender As Object, ByVal e As System.Windows.Forms.MouseEventArgs) Handles Button12.MouseClick Dim NoAcc As String Dim NoAccmod2 As String Dim NoPas As String Dim sqlcon As New MySqlConnection("Server=localhost; Database=school;Uid=root;Pwd=nitoryolai123$%^;") Dim sqlcom As MySqlCommand = New MySqlCommand("Select * from student where IDNO= '" & TextBox14.Text & "' ", sqlcon) sqlcon.Open() Dim rdr As MySqlDataReader rdr = sqlcom.ExecuteReader If rdr.HasRows Then rdr.Read() NoAcc = rdr("IDNO") If (TextBox14.Text <> NoAcc) Then MsgBox("ID Number is not yet registered!, please register first in the general information before trying to register parents information", MsgBoxStyle.Information) TextBox7.Enabled = False TextBox8.Enabled = False TextBox9.Enabled = False TextBox10.Enabled = False TextBox11.Enabled = False TextBox12.Enabled = False TextBox13.Enabled = False End If End If

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  • Why is execution-time method resolution faster than compile-time resolution?

    - by Felix
    At school, we about virtual functions in C++, and how they are resolved (or found, or matched, I don't know what the terminology is -- we're not studying in English) at execution time instead of compile time. The teacher also told us that compile-time resolution is much faster than execution-time (and it would make sense for it to be so). However, a quick experiment would suggest otherwise. I've built this small program: #include <iostream> #include <limits.h> using namespace std; class A { public: void f() { // do nothing } }; class B: public A { public: void f() { // do nothing } }; int main() { unsigned int i; A *a = new B; for (i=0; i < UINT_MAX; i++) a->f(); return 0; } Where I made A::f() once normal, once virtual. Here are my results: [felix@the-machine C]$ time ./normal real 0m25.834s user 0m25.742s sys 0m0.000s [felix@the-machine C]$ time ./virtual real 0m24.630s user 0m24.472s sys 0m0.003s [felix@the-machine C]$ time ./normal real 0m25.860s user 0m25.735s sys 0m0.007s [felix@the-machine C]$ time ./virtual real 0m24.514s user 0m24.475s sys 0m0.000s [felix@the-machine C]$ time ./normal real 0m26.022s user 0m25.795s sys 0m0.013s [felix@the-machine C]$ time ./virtual real 0m24.503s user 0m24.468s sys 0m0.000s There seems to be a steady ~1 second difference in favor of the virtual version. Why is this? Relevant or not: dual-core pentium @ 2.80Ghz, no extra applications running between two tests. Archlinux with gcc 4.5.0. Compiling normally, like: $ g++ test.cpp -o normal Also, -Wall doesn't spit out any warnings, either.

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  • Can someone copyright an SQL query?

    - by Samutz
    I work for a school district. Every year we have to export a list of students from our student management system and send it to a company that handles our online exams. So to do this export, we had to hire someone who knew the inner workings of our student management system. He wrote an sql (Adaptive Sybase SQL Anywhere) query to export the students to a csv file like we needed. This was before I started working for the district, so for a while I assumed this was an actually application, until it came time for me to do the export myself. And every year he charges us $500 to update this query to export the students for the current year. So when I discovered it was only a query (.bat file and .sql file), my thought was "I can update this myself". All I have to do is change the years in the query (eg. 2009 to 2010). The query (.sql file) itself has this comment at the top: // This code was writtend by [the guy] // and is the property of [his company]...Copyright 2005,2006,2008,2009 // This code MAY NOT BE USED without the expressed written consent of // [his company]. (Yes, it really does says "writtend".) So now my boss is worried that we're violating the copyright. And that the guy is gonna find out that I updated the query myself because we haven't asked him to update it this year and take legal action. So back to the subject's question: Can he really copyright this query? And if so, is modifying it ourselves a copyright violation? In my mind, a single query isn't program code. It's more a command line command. But I don't know what it's considered legally.

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  • What is the name of this geometrical function?

    - by Spike
    In a two dimentional integer space, you have two points, A and B. This function returns an enumeration of the points in the quadrilateral subset bounded by A and B. A = {1,1} B = {2,3} Fn(A,B) = {{1,1},{1,2},{1,3},{2,1},{2,2},{2,3}} I can implement it in a few lines of LINQ. private void UnknownFunction(Point to, Point from, List<Point> list) { var vectorX = Enumerable.Range(Math.Min(to.X, from.X), Math.Abs(to.X - from.Y) + 1); var vectorY = Enumerable.Range(Math.Min(to.Y, from.Y), Math.Abs(to.Y - from.Y) + 1); foreach (var x in vectorX) foreach (var y in vectorY) list.Add(new Point(x, y)); } I'm fairly sure that this is a standard mathematical operation, but I can't think what it is. Feel free to tell me that it's one line of code in your language of choice. Or to give me a cunning implementation with lambdas or some such. But mostly I just want to know what it's called. It's driving me nuts. It feels a little like a convolution, but it's been too long since I was at school for me to be sure.

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  • DIVS over flash movies in Internet Explorer

    - by drew
    The age old question... why the hell doesn't a div positioned over a flash object stay on top with z-index. I have found the answer in the past, but it's been so long, I can't seem to get it. My flash movie is in a div floating left: <div id="flash"> <object width="614" height="289"> <param name="movie" value="images/75.swf"> <param name="wmode" value="transparent"> <embed src="images/75.swf" width="614" height="289" wmode"transparent"> </embed> </object> </div> My css for the div that needs to be on top is: .menu ul li:hover ul li a:hover { background:#5a3f2d; color:#FFF; z-index: 9999; I cannot get it to show above the flash movie in ie6 or ie8. I know this is old school but I'm frustrated! Does my nav div need to have an absolute position? Is that why it doesn't work? Example is here. Hover over the first link on the right: "CUSTOMER SERVICE" Thanks all :)

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  • Emailing smtp with Python error

    - by jakecar
    I can't figure out why this isn't working. I'm trying to send an email from my school email address with this code I got online. The same code works for sending from my GMail address. Does anyone know what this error means? The error occurs after waiting for about one and a half minutes. import smtplib FROMADDR = "FROM_EMAIL" LOGIN = "USERNAME" PASSWORD = "PASSWORD" TOADDRS = ["TO_EMAIL"] SUBJECT = "Test" msg = ("From: %s\r\nTo: %s\r\nSubject: %s\r\n\r\n" % (FROMADDR, ", ".join(TOADDRS), SUBJECT) ) msg += "some text\r\n" server = smtplib.SMTP('OUTGOING_SMTP', 587) server.set_debuglevel(1) server.ehlo() server.starttls() server.login(LOGIN, PASSWORD) server.sendmail(FROMADDR, TOADDRS, msg) server.quit() And here's the error I get: Traceback (most recent call last): File "emailer.py", line 13, in server = smtplib.SMTP('OUTGOING_SMTP', 587) File "/Library/Frameworks/Python.framework/Versions/2.6/lib/python2.6/smtplib.py", line 239, in init (code, msg) = self.connect(host, port) File "/Library/Frameworks/Python.framework/Versions/2.6/lib/python2.6/smtplib.py", line 295, in connect self.sock = self._get_socket(host, port, self.timeout) File "/Library/Frameworks/Python.framework/Versions/2.6/lib/python2.6/smtplib.py", line 273, in _get_socket return socket.create_connection((port, host), timeout) File "/Library/Frameworks/Python.framework/Versions/2.6/lib/python2.6/socket.py", line 514, in create_connection raise error, msg socket.error: [Errno 60] Operation timed out

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  • Accessing items separated by -componentsSeparatedByString

    - by Graeme
    Hi, I have an array gathered by componentsSeparatedByString: that looks like the following when I use po in the GDB after the array has gone through componentsSeparatedByString: "\n\t\t <b>Suburb, </b> BAIRNSDALE", "\n\t\t <b>Address, </b> 15K NW BAIRNSDALE", "\n\t\t <b>Reference, </b> MELWOOD/SCHOOL ROAD", "\n\t\t <b>Last Changed, </b> 09/04/10 05, 29, 00 PM", "\n\t\t <b>Type, </b> HOME", "\n\t\t <b>Status, </b> BUILT", "\n\t\t <b>Property Size, </b> 2.00 HA.", "\n\t\t <b>Residents, </b> 2", "\n\t\t <b>First Added Date/Time, </b> 09/04/10 03, 15, 00 PM", "\n\t\t\t" Only problem is, I now can't figure out where to go from here. I need to be able to access each of these items (i.e. type, status, property size) separately rather than just calling the entire array (i.e. currentProperty.status). How do I do this? Also what's with all the n\t\t\t things - how do I get rid of them? Thanks.

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