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  • How do I manipulate the format on a DataGridView that is bound to a Data Source?

    - by Jack Johnstone
    I´m using SQL Server 2005 and Visual Studio 2008, C#. In the data source (the SQL Server data table) I use the DateTime format mm/dd/yyyy, however, in a forms overview (DataGridView) users would like to see a completely other format, with year, week number and day number of week (yyww,d) which is in string format. I´ve created an algorithm for the transformation between values (date to weekday), but can I populate the affected cells with yyww,d (string) instead of mm/dd/yyyy (DateTime)? This is what I´ve been testing out, without success (and note, it´s on the last line the problem becomes obvious, as the cell value won´t accept a string on runtime - it still wants to be a DateTime...) private void DataGridViewQueryFindRequests_CellFormatting( object sender, DataGridViewCellFormattingEventArgs e) { string weekAndDay = ""; DataGridViewCell cell = DataGridViewQueryFindRequests.Rows[e.RowIndex].Cells[e.ColumnIndex]; if (cell.ColumnIndex == 13 && cell.Value == null) mEmptyRow = true; if ((cell.ColumnIndex == 14 || cell.ColumnIndex == 15) && !mEmptyRow) { weekAndDay = ClassWeeksAndDates.dateToWeekNumber(Convert.ToDateTime(cell.Value)); cell.ValueType = typeof(string); cell.Value = weekAndDay; } }

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  • How do I show the selected item in an HTML <select> at the top

    - by Michael Meadows
    I have an HTML select that looks something like this (values are fake) <select size="40"> <option value="1">What would you do if I sang out of tune,</option> <option value="2">Would you stand up and walk out on me?</option> ... more <option value="156">Lend me your ears, and I'll sing you a song,</option> <option selected="selected" value="157">I will try not to sing out of key.</option> <option value="158">Oh, I get by with a little help from my friends.</option> ... more <option value="507">I get high with a little help from my friends.</option> <option value="509">Gonna' try with a little from my friends.</option> </select> The problem that I have is that when displaying the list after loading the page and the selected option is in the middle of the very long list, IE scrolls the selected option to the top of the list (which is what I want). Firefox, Chrome, Opera, and Safari show it at the bottom (which I don't want). I have to assume that IE is doing it wrong since everyone else shows it at the bottom. How can I force the browsers to display the selected item at the top of the list. I do not want to put it at the top of the list, I just want it to scroll such that the selected option is at the top. bonus, it would be even better if I can put it fourth from the top, but I can live without that if it's too difficult.

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  • Multiple Foreign keys to a single table and single key pointing to more than one table

    - by user1216775
    I need some suggestions from the database design experts here. I have around six foreign keys into a single table (defect) which all point to primary key in user table. It is like: defect (.....,assigned_to,created_by,updated_by,closed_by...) If I want to get information about the defect I can make six joins. Do we have any better way to do it? Another one is I have a states table which can store one of the user-defined set of values. I have defect table and task table and I want both of these tables to share the common state table (New, In Progress etc.). So I created: task (.....,state_id,type_id,.....) defect(.....,state_id,type_id,...) state(state_id,state_name,...) importance(imp_id,imp_name,...) There are many such common attributes along with state like importance(normal, urgent etc), priority etc. And for all of them I want to use same table. I am keeping one flag in each of the tables to differentiate task and defect. What is the best solution in such a case? If somebody is using this application in health domain, they would like to assign different types, states, importances for their defect or tasks. Moreover when a user selects any project I want to display all the types,states etc under configuration parameters section.

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  • JDBC with JSP fails to insert

    - by StrykeR
    I am having some issues right now with JDBC in JSP. I am trying to insert username/pass ext into my MySQL DB. I am not getting any error or exception, however nothing is being inserted into my DB either. Below is my code, any help would be greatly appreciated. <% String uname=request.getParameter("userName"); String pword=request.getParameter("passWord"); String fname=request.getParameter("firstName"); String lname=request.getParameter("lastName"); String email=request.getParameter("emailAddress"); %> <% try{ String dbURL = "jdbc:mysql:localhost:3306/assi1"; String user = "root"; String pwd = "password"; String driver = "com.mysql.jdbc.Driver"; String query = "USE Users"+"INSERT INTO User (UserName, UserPass, FirstName, LastName, EmailAddress) " + "VALUES ('"+uname+"','"+pword+"','"+fname+"','"+lname+"','"+email+"')"; Class.forName(driver); Connection conn = DriverManager.getConnection(dbURL, user, pwd); Statement statement = conn.createStatement(); statement.executeUpdate(query); out.println("Data is successfully inserted!"); } catch(SQLException e){ for (Throwable t : e) t.printStackTrace(); } %> DB script here: CREATE DATABASE Users; use Users; CREATE TABLE User ( UserID INT NOT NULL AUTO_INCREMENT, UserName VARCHAR(20), UserPass VARCHAR(20), FirstName VARCHAR(30), LastName VARCHAR(35), EmailAddress VARCHAR(50), PRIMARY KEY (UserID) );

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  • Adding validations without knowing the fields

    - by Frexuz
    My example form <% form_for @ad do |f| %> <%= f.error_messages %> <p> <%= f.label :ad_type_id %><br /> <%= f.collection_select(:ad_type_id, AdType.all, :id, :name) %> </p> <p> <% @ad.ad_properties.each do |property| %> <%= property.name %>: <% f.fields_for :ad_values do |value_field| %> <%= value_field.text_field :ad_id, :value => @ad.id %> <%= value_field.text_field :ad_property_id, :value => property.id %> <%= value_field.text_field :value %> <% end %><br /><br /> <% end %> </p> <p> <%= f.label :description %><br /> <%= f.text_area :description %> </p> <p><%= f.submit %></p> <% end %> Explanation: Ad has many properties. I can add new properties at any time (it's a normal model). Lets say the Ad is of the type 'hotel'. Then I would add properties like 'stars' and 'breakfast_included' Then I store each of these properties' values in a separate model. And all this works fine with my form above. My problem: These fields are not validated because I can't know what their names are. I need to add validations dynamically somehow. My thought: #Before the normal validations kick in def add_validations self.properties.each do |property| property.add_validation :whatever #somehow :) end end How could I do this?

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  • Function to extract data in insert into satement for a table.

    - by user269484
    Hi...I m using this Function to extract the data but unable to extract LONG datatype. Can anyone help me? create or replace Function ExtractData(v_table_name varchar2) return varchar2 As b_found boolean:=false; v_tempa varchar2(8000); v_tempb varchar2(8000); v_tempc varchar2(255); begin for tab_rec in (select table_name from user_tables where table_name=upper(v_table_name)) loop b_found:=true; v_tempa:='select ''insert into '||tab_rec.table_name||' ('; for col_rec in (select * from user_tab_columns where table_name=tab_rec.table_name order by column_id) loop if col_rec.column_id=1 then v_tempa:=v_tempa||'''||chr(10)||'''; else v_tempa:=v_tempa||',''||chr(10)||'''; v_tempb:=v_tempb||',''||chr(10)||'''; end if; v_tempa:=v_tempa||col_rec.column_name; if instr(col_rec.data_type,'CHAR') 0 then v_tempc:='''''''''||'||col_rec.column_name||'||'''''''''; elsif instr(col_rec.data_type,'DATE') 0 then v_tempc:='''to_date(''''''||to_char('||col_rec.column_name||',''mm/dd/yyyy hh24:mi'')||'''''',''''mm/dd/yyyy hh24:mi'''')'''; else v_tempc:=col_rec.column_name; end if; v_tempb:=v_tempb||'''||decode('||col_rec.column_name||',Null,''Null'','||v_tempc||')||'''; end loop; v_tempa:=v_tempa||') values ('||v_tempb||');'' from '||tab_rec.table_name||';'; end loop; if Not b_found then v_tempa:='-- Table '||v_table_name||' not found'; else v_tempa:=v_tempa||chr(10)||'select ''-- commit;'' from dual;'; end if; return v_tempa; end; /

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  • Error in inserting data into database

    - by Matthew
    When I try to run this code it will not insert the data into the database? <?php class Database { private $dsn; function __construct($dbname, $host, $user, $password, $enckey) { $this->dsn = "mysql:dbname=" . $dbname . ';host=' . $host; $this->user = $user; $this->password = $password; } private function createDSN() { return $this->dsn; } public function createConnection() { try { $dbh = new PDO(self::createDSN(), $this->user, $this->password); } catch (PDOException $e) { echo 'Connection failed: ' . $e->getMessage(); } return $dbh; } } $db = new Database('mytest', 'localhost', 'root', 'hashedpassword', null); $dbh = $db->createConnection(); $sql = $dbh->prepare("INSERT INTO contacts (firstname, lastname) VALUES (?,?)"); $sql->execute(array("abc", "xyz")); ?>

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  • What rules govern the copying of variables in Javascript closures?

    - by int3
    I'd just like to check my understanding of variable copying in Javascript. From what I gather, variables are passed/assigned by reference unless you explicitly tell them to create a copy with the new operator. But I'm a little uncertain when it comes to using closures. Say I have the following code: var myArray = [1, 5, 10, 15, 20]; var fnlist = []; for (var i in myArray) { var data = myArray[i]; fnlist.push(function() { var x = data; console.log(x); }); } fnlist[2](); // returns 20 I gather that this is because fnlist[2] only looks up the value of data at the point where it is invoked. So I tried an alternative tack: var myArray = [1, 5, 10, 15, 20]; var fnlist = []; for (var i in myArray) { var data = myArray[i]; fnlist.push(function() { var x = data; return function() { console.log(x); } }()); } fnlist[2](); // returns 10 So now it returns the 'correct' value. Am I right to say that it works because a function resolves all variable references to their 'constant' values when it is invoked? Or is there a better way to explain it? Any explanations / links to explanations regarding this referencing / copying business would be appreciated as well. Thanks!

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  • How can I use Perl to determine whether the contents of two files are identical?

    - by Zaid
    This question comes from a need to ensure that changes I've made to code doesn't affect the values it outputs to text file. Ideally, I'd roll a sub to take in two filenames and return 1or return 0 depending on whether the contents are identical or not, whitespaces and all. Given that text-processing is Perl's forté, it should be quite easy to compare two files and determine whether they are identical or not (code below untested). use strict; use warnings; sub files_match { my ( $fileA, $fileB ) = @_; open my $file1, '<', $fileA; open my $file2, '<', $fileB; while (my $lineA = <$file1>) { next if $lineA eq <$file2>; return 0 and last; } return 1; } The only way I can think of (sans CPAN modules) is to open the two files in question, and read them in line-by-line until a difference is found. If no difference is found, the files must be identical. But this approach is limited and clumsy. What if the total lines differ in the two files? Should I open and close to determine line count, then re-open to scan the texts? Yuck. I don't see anything in perlfaq5 relating to this. I want to stay away from modules unless they come with the core Perl 5.6.1 distribution.

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  • alternative in .Net to building Tables/TR/TD manually?

    - by egrunin
    I've got a pile of code here that looks like this: if (stateTax > 0) { tr = new TableRow(); tbl.Rows.Add(tr); td = new TableCell(); td.CssClass = "stdLabel"; td.Text = "NY State Tax"; tr.Cells.Add(td); td = new TableCell(); td.Text = string.Format("{0:C}", stateTax); td.CssClass = "justRight"; tr.Cells.Add(td); } This is a horrible hash of data and layout, but creating a special class or control every time something like this comes up seems almost as bad. What I usually do is write a helper function, which is concise but ugly: if (stateTax > 0) MakeRow(tbl, "NY State Tax", "stdLabel", string.Format("{0:C}", stateTax), "justRight"); And now I'm thinking: haven't I done this 100 times before? Isn't there a more modern way? Just to be explicit: it's a whole list of miscellaneous labels and values. They don't come from any particular data source, and the rules for when rows should be suppressed vary. This example has only two columns, but I have other places with more.

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  • what is the most elegant way of showing first week in a month

    - by ooo
    In C#, i want to show the first week in a calendar (in a html table) and i am trying to figure out the most elegant algorithm to generate the right days. If the first day of the week is not Sunday, i want to show the days of preceding month (like you would see on a regular calendar). So, as an input you have a current month. In this case May. I want to generate this: Month: May <table> <tr> <th>S</th> <th>M</th> <th>T</th> <th>W</th> <th>TH</th> <th>F</th> <th>Sa</th> </tr> <tr> <td>25</td> <td>26</td> <td>27</td> <td>28</td> <td>29</td> <td>30</td> <td>1</td> </tr></table> so it should display something like this (ignore the alignment) S | M | T | W | Th | F | Sa | 25 - 26 - 27 - 28 - 29 - 30 - 1 given that each month would have the start of day be a different day of the week, i am trying to figure out an elegant way to get the values of this data using the DateTime object. I see it has a dayofweek property on a date. i am generating this table in C# on my server to pass down to a html page.

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  • String generator issue

    - by Andrey
    I want to write a method which returns a string. So far so good. The creation of the string however is quite complicated. I have 3 string lists - the first one has 155 entries, the second one - 9, the third one 21. I want my method if called enough times(155*9*21) to return all the possible combinations of values from the 3 lists (basically this method should keep count on how many times it was called and return only one combination each time). Any ideas how to accomplish that? I have 155*9*22 possible combinations. The first time the method is called it should take List1(0), List2(0), List3(0). After that in the next 21 iterations, the index of the third list is only changed. Once all the elements from the third list have been used increment the index of the second list and so on. Once the method has produced all the possible combinations (155*9*22) I want it to start from the beginning.

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  • Assistance with CC Processing script

    - by JM4
    I am currently implementing a credit card processing script, most as provided by the merchant gateway. The code calls functions within a class and returns a string based on the response. The end php code I am using (details removed of course) with example information is: <?php $gw = new gwapi; $gw->setLogin("username", "password"); $gw->setBilling("John","Smith","Acme, Inc.","888","Suite 200", "Beverly Hills", "CA","77777","US","555-555-5555","555-555-5556","[email protected]", "www.example.com"); // "CA","90210","US","[email protected]"); $gw->setOrder("1234","Big Order",1, 2, "PO1234","65.192.14.10"); $r = $gw->doSale("1.00","4111111111111111","1010"); print $gw->responses['responsetext']; ?> where setlogin allows me to login, setbilling takes the sample consumer information, set order takes the order id and description, dosale takes the amount charged, cc number and exp date. when all the variables are sent validated then sent off for processing, a string is returned in the following format: response=1&responsetext=SUCCESS&authcode=123456&transactionid=23456&avsresponse=M&orderid=&type=sale&response_code=100 where: response = transaction approved or declined response text = textual response authcode = transaction authorization code transactionid = payment gateway tran id avsresponse = avs response code orderid = original order id passed in tran request response_code = numeric mapping of processor response I am trying to solve for the following: How do I take the data which is passed back and display it appropriately on the page - If the transaction failed or AVS code doesnt match my liking or something is wrong, an error is displayed to the consumer; if the transaction processed, they are taken to a completion page and the transaction id is sent in SESSION as output to the consumer If the response_code value matches a table of values, certain actions are taken, i.e. if code =100, take to success page, if code = 300 print specific error on original page to customer, etc.

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  • Ruby - RegEx problem or maybe another solution altogether

    - by r3nrut
    Ok the problem I'm having is that I have a block of javascript I've successfully scraped out of a websites source and now I have to sift through the js to get the specific values I'm looking for. Below is the chunk i'm needing to deal with. I need to find "flvFileName" and get all the file names listed. In this case its: trailer1,trailer2,trailer3. At first I started using regex to match the start and end tags and them match the file names and extract them to an array but the problem is that there isn't always 3 videos in the list. Could be 0, 1, 2, 3, 4 etc. So matching doesn't work. Any thoughts on a way to approach this that won't make me continue to abuse my laptop? ["", "\r\n", "\n", "\r\n function IgnoreEnter(e) {\r\n var code;\r\n if (!e) // IE\r\n {\r\n var e = window.event;\r\n }\r\n if (e.keyCode) {\r\n code = e.keyCode;\r\n }\r\n else if (e.which) // Firefox, Opera\r\n {\r\n code = e.which;\r\n }\r\n\r\n if (code == 13) {\r\n e.cancelBubble = true;\r\n e.returnValue = false;\r\n }\r\n }\r\n\r\n function ResetDefault() {\r\n __defaultFired = false;\r\n }\r\n", "", "\r\n// <![CDATA[\r\n$(doc).ready(function () { $('#VideoObject').flash({ swf: '/scinema/video.swf', height: 300, width: 480, hasVersion: 8, menu: false, wmode: 'transparent', bgcolor: '#000',flashvars: {flvFileName: 'trailer1,trailer2,trailer3', age: 'no', isForced: 'true'} }); });

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  • Error using maven profiles

    - by user3127896
    I've added two profiles to my application and that how it looks: <profiles> <profile> <id>dev</id> <properties> <db.username>root</db.username> <db.password>root</db.password> <db.connectionURL>localhost:3306</db.connectionURL> <db.driverClass>com.mysql.jdbc.Driver</db.driverClass> </properties> </profile> <profile> <id>prod</id> <properties> <db.username>prodroot</db.username> <db.password>prodpass</db.password> <db.connectionURL>localhost:3306</db.connectionURL> <db.driverClass>com.mysql.jdbc.Driver</db.driverClass> </properties> </profile> </profiles> In my jdbc.properties file i changed values like this: jdbc.driverClassName=${db.driverClass} jdbc.dialect=org.hibernate.dialect.MySQLDialect jdbc.databaseurl=jdbc:mysql://${db.connectionURL}/dbname jdbc.username=${db.username} jdbc.password=${db.password} And here's bean from spring-container.xml <bean id="dataSource" class="org.apache.commons.dbcp.BasicDataSource" destroy-method="close" p:driverClassName="${jdbc.driverClassName}" p:url="${jdbc.databaseurl}" p:username="${jdbc.username}" p:password="${jdbc.password}" /> When i try to deploy my application i got following error: SEVERE: Exception sending context initialized event to listener instance of class org.springframework.web.context.ContextLoaderListener org.springframework.beans.factory.BeanDefinitionStoreException: Invalid bean definition with name 'dataSource' defined in ServletContext resource [/WEB-INF/spring-servlet.xml]: Could not resolve placeholder 'db.driverClass' Structure of project: Any ideas what i'm doing wrong? Thanks in advance!

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  • Create an Oracle function that returns a table

    - by Craig
    I'm trying to create a function in package that returns a table. I hope to call the function once in the package, but be able to re-use its data mulitple times. While I know I create temp tables in Oracle, I was hoping to keep things DRY. So far, this is what I have: Header: CREATE OR REPLACE PACKAGE TEST AS TYPE MEASURE_RECORD IS RECORD ( L4_ID VARCHAR2(50), L6_ID VARCHAR2(50), L8_ID VARCHAR2(50), YEAR NUMBER, PERIOD NUMBER, VALUE NUMBER ); TYPE MEASURE_TABLE IS TABLE OF MEASURE_RECORD; FUNCTION GET_UPS( TIMESPAN_IN IN VARCHAR2 DEFAULT 'MONTLHY', STARTING_DATE_IN DATE, ENDING_DATE_IN DATE ) RETURN MEASURE_TABLE; END TEST; Body: CREATE OR REPLACE PACKAGE BODY TEST AS FUNCTION GET_UPS ( TIMESPAN_IN IN VARCHAR2 DEFAULT 'MONTLHY', STARTING_DATE_IN DATE, ENDING_DATE_IN DATE ) RETURN MEASURE_TABLE IS T MEASURE_TABLE; BEGIN SELECT ... INTO T FROM ... ; RETURN T; END GET_UPS; END TEST; The header compiles, the body does not. One error message is 'not enough values', which probably means that I should be selecting into the MEASURE_RECORD, rather than the MEASURE_TABLE. What am I missing?

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  • How do I parse data received in a memorystream?

    - by Kerberos42
    I'm new to using sockets. I have a very basic client that sends a request, and waits for a response. The response is one stream, but has two parts. The first part is prefixed with ANS and is a set of key/value pairs in this form: KEY:Value with each pair on a separate line. The second part of the response is prefixed by RCT and this is pre-formatted text that needs to be send directly to a printer. So what would be the best way to extract both parts of the response, and in the first part, get each Key:Value pair. I might not even need them all, but I have to look at each one to see what the values are then decide what to do with it. I'm currently writing the response out to a textbox just to understand what its doing, but now I need to actually do something with the data. Here's a data sample, as it is received: ANS Result: Data Received RCPRES:Q[81] TML:123 OPP: MRR:000000999999 <several dozen more KEY:Value pairs> RCTNov 05 2013 04:03 pm Trans# 123456 <pre-formatted text>

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  • C++ Template Iterator error

    - by gprime
    I am going over some code i wrote in 2006 as an undergrad. It's a simple genetic algorithm library written in C++ using templates. It use to work in 2006 when i coded it with visual studio, but now when i am trying to run it in xcode i get compile errors. This function is giving me errors: friend bool operator==(const TSPGenome<T> & t1, const TSPGenome<T> & t2) { // loop through each interator and check to see if the two genomes have the same values if(t1.genome_vec->size() != t2.genome_vec->size()) return false; else { // iterate through each vector<T>::iterator it_t1; vector<T>::iterator it_t2; it_t1 = t1.genome_vec->begin(); for(it_t2 = t2.genome_vec->begin(); it_t2 != t2.genome_vec->end(); ++it_t2, ++it_t1) { if(*it_t2 != *it_t1) return false; } } // everything seems good return true; } xcode complains about these two lines not having ; before it_t1 and it_t2. vector<T>::iterator it_t1; vector<T>::iterator it_t2; Is it because the vector type it T? I declared it in the class as follows: template <typename T> class TSPGenome : public Genome { Any help would be appreciated. Thanks!

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  • DynamicContent.html: Write a JavaScript in an HTML document that can change the content of an HTML e

    - by A sw A
    ShowHide.html: Write a JavaScript in an HTML document that displays an image and allows the user to toggle the image between appearing and not appearing in the document. Place your image in a (division) tag that has a style attribute. “style.visibility” can take two values: “visible” and “hidden”. The document has a button called “Toggle Image”, which calls the toggle function upon the event “onclick”. DynamicColors.html: Write a JavaScript in an HTML document that changes the background and foreground colors of the body of a document according to the user input. The document has two input texts: background color and foreground color. The colors change when the event “onchange” occurs as you type in the text input and the event handler is called. Your event handler takes two parameters: “where”, and “newColor”. To change the document color and background color you need to change the elements document.body.style.color and document.body.style.backgroundColor. Available colors are: black, silver, gray, white, maroon, red, purple, fuchsia, green, lime, olive, yellow, navy, blue, teal, and aqua. DynamicContent.html: Write a JavaScript in an HTML document that can change the content of an HTML element (a help box). The content of an element is accessed through its “value” property. The content of a help box can change depending on the placement of the mouse cursor. When the cursor is placed over a particular input field (“onmouseover” event), the help box can display advice on how the field is to be filled. When the cursor is moved away from the input field (“onmouseout” event), the help box content changes to simply indicate that assistance is available. Your messages are stored in an array of strings.

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  • C# Function Inheritance--Use Child Class Vars with Base Class Function

    - by Sean O'Connor
    Good day, I have a fairly simple question to experienced C# programmers. Basically, I would like to have an abstract base class that contains a function that relies on the values of child classes. I have tried code similar to the following, but the compiler complains that SomeVariable is null when SomeFunction() attempts to use it. Base class: public abstract class BaseClass { protected virtual SomeType SomeVariable; public BaseClass() { this.SomeFunction(); } protected void SomeFunction() { //DO SOMETHING WITH SomeVariable } } A child class: public class ChildClass:BaseClass { protected override SomeType SomeVariable=SomeValue; } Now I would expect that when I do: ChildClass CC=new ChildClass(); A new instance of ChildClass should be made and CC would run its inherited SomeFunction using SomeValue. However, this is not what happens. The compiler complains that SomeVariable is null in BaseClass. Is what I want to do even possible in C#? I have used other managed languages that allow me to do such things, so I certain I am just making a simple mistake here. Any help is greatly appreciated, thank you.

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  • While in a transaction, how can reads to an affected row be prevented until the transaction is done?

    - by Mahn
    I'm fairly sure this has a simple solution, but I haven't been able to find it so far. Provided an InnoDB MySQL database with the isolation level set to SERIALIZABLE, and given the following operation: BEGIN WORK; SELECT * FROM users WHERE userID=1; UPDATE users SET credits=100 WHERE userID=1; COMMIT; I would like to make sure that as soon as the select inside the transaction is issued, the row corresponding to userID=1 is locked for reads until the transaction is done. As it stands now, UPDATEs to this row will wait for the transaction to be finished if it is in process, but SELECTs simply will read the previous value. I understand this is the expected behaviour in this case, but I wonder if there is a way to lock the row in such a way that SELECTs will also wait until the transaction is finished to return the values? The reason I'm looking for that is that at some point, and with enough concurrent users, it could happen that while the previous transaction is in process someone else reads the "credits" to calculate something else. Ideally the code run by that someone else should wait for the transaction to finish to use the new value, because otherwise it could lead to irreversible desync issues. Note that I don't want to lock the entire table for reads, just the specific row. Also, I could add a boolean "locked" field to the tables and set it to 1 every time I'm starting a transaction but I don't really feel this is the most elegant solution here, unless there is absolutely no other way to handle this through mysql directly.

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  • jQuery async ajax query and returning value problem (scope, closure)

    - by glebovgin
    Hi. Code not working because of async query and variable scope problem. I can't understand how to solve this. Change to $.ajax method with async:false - not an option. I know about closures, but how I can implement it here - don't know. I've seen all topics here about closures in js and jQuery async problems - but still nothing. Help, please. Here is the code: var map = null; var marker; var cluster = null; function refreshMap() { var markers = []; var markerImage = new google.maps.MarkerImage('/images/image-1_32_t.png', new google.maps.Size(32, 32)); $.get('/get_users.php',{},function(data){ if(data.status == 'error') return false; var users = data.users; // here users.length = 1 - this is ok; for(var i in users) { //here I have every values from users - ok var latLng = new google.maps.LatLng(users[i].lat, users[i].lng); var mark = new google.maps.Marker({ position: latLng, icon: markerImage }); markers.push(mark); alert(markers.length); // length 1 } },'json'); alert(markers.length); // length 0 //if I have alert() above - I get result cluster = new MarkerClusterer(map, markers, { maxZoom: null, gridSize: null }); } Thanks.

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  • C#: How to implement a smart cache

    - by Svish
    I have some places where implementing some sort of cache might be useful. For example in cases of doing resource lookups based on custom strings, finding names of properties using reflection, or to have only one PropertyChangedEventArgs per property name. A simple example of the last one: public static class Cache { private static Dictionary<string, PropertyChangedEventArgs> cache; static Cache() { cache = new Dictionary<string, PropertyChangedEventArgs>(); } public static PropertyChangedEventArgs GetPropertyChangedEventArgsa(string propertyName) { if (cache.ContainsKey(propertyName)) return cache[propertyName]; return cache[propertyName] = new PropertyChangedEventArgs(propertyName); } } But, will this work well? For example if we had a whole load of different propertyNames, that would mean we would end up with a huge cache sitting there never being garbage collected or anything. I'm imagining if what is cached are larger values and if the application is a long-running one, this might end up as kind of a problem... or what do you think? How should a good cache be implemented? Is this one good enough for most purposes? Any examples of some nice cache implementations that are not too hard to understand or way too complex to implement?

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  • How can I quickly parse large (>10GB) files?

    - by Andrew
    Hi - I have to process text files 10-20GB in size of the format: field1 field2 field3 field4 field5 I would like to parse the data from each line of field2 into one of several files; the file this gets pushed into is determined line-by-line by the value in field4. There are 25 different possible values in field2 and hence 25 different files the data can get parsed into. I have tried using Perl (slow) and awk (faster but still slow) - does anyone have any suggestions or pointers toward alternative approaches? FYI here is the awk code I was trying to use; note I had to revert to going through the large file 25 times because I wasn't able to keep 25 files open at once in awk: chromosomes=(1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25) for chr in ${chromosomes[@]} do awk < my_in_file_here -v pat="$chr" '{if ($4 == pat) for (i = $2; i <= $2+52; i++) print i}' >> my_out_file_"$chr".query done

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  • Query not being executed

    - by user2385241
    I'm trying to create a script that allows me to upload an image, grab the details sent through inputs (a description and chosen project number) and insert this information into a table. I currently have this function: public function NewEntry() { $connect = new dbconnect; $_SESSION['rnd'] = substr(number_format(time() * rand(),0,'',''),0,15); $allowedExts = array("gif", "jpeg", "jpg", "png"); $size = $_FILES["file"]["size"]; $path = $_FILES["file"]["name"]; $extension = pathinfo($path, PATHINFO_EXTENSION); $pr = $_POST['project']; $cl = $_POST['changelog']; $file = $_SESSION['rnd'] . "." . $extension; if (in_array($extension, $allowedExts) && $size < 200000000) { if ($_FILES["file"]["error"] == 0) { if (!file_exists("../uploads/" . $_SESSION['rnd'])) { move_uploaded_file($_FILES["file"]["tmp_name"], "../uploads/" . $_SESSION['rnd'] . "." . $extension); } } } else { echo "File validation failed."; } $row = $connect->queryExecute("INSERT INTO entries(project,file,changelog)VALUES($pr,$file,$cl)"); header('location:http://www.example.com/admin'); } When the form is posted the function runs, the image uploads but the query isn't executed. The dbconnect class isn't at fault as it's untampered and has been used in past projects. The error logs don't give any output and no MySQL errors show. Any ideas?

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