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  • ASP.NET MVC 2: HtmlHelpers, foreach?

    - by dcolumbus
    This one is new to me... I'm bringing in a Model that represents a list of items. Some items should be rendered as a number of checkboxes and radios. Others will be rendered in a list. Now I know how to foreach the items and spit them out manually... but I'd like to be able to check them against the Model that I have, making sure that at least one optios is selected/chosen. And obviously display the associated validation errors. This is how I am displaying the checkbox items manually: <ul> <% foreach (Corporate.Entities.DesignLayout.Tag tag in Model.DesignOptions.Items) { %> <li><input type="checkbox" /><%: tag.TagName %></li> <% } %> </ul> Two questions arise: 1) How do I check that list of checkboxes against my model? 2) How would I render the tag items with an HtmlHelper SelectList? Example: <%: Html.ListBoxFor(m=>m.DesignOptions, [don't know what I should put here]) %>

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  • how can i redirect page while download box appears?

    - by Ronnie Chester Lynwood
    Now I got this code; <?php $file = "pain.png"; if (file_exists($file)) { header('Content-Description: File Transfer'); header('Content-Type: application/octet-stream'); header('Content-Disposition: attachment; filename='.basename($file)); header('Content-Transfer-Encoding: binary'); header('Expires: 0'); header('Cache-Control: must-revalidate, post-check=0, pre-check=0'); header('Pragma: public'); header('Content-Length: ' . filesize($file)); ob_clean(); flush(); readfile($file); exit; } ?> This code appears a download box. But I want to redirect this page to "Thank You" page while download box still here. How can i do this? Thanks...

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  • Drupal 6 Validation for Form Callback Function

    - by Wade
    I have a simple form with a select menu on the node display page. Is there an easy way to validate the form in my callback function? By validation I don't mean anything advanced, just to check that the values actually existed in the form array. For example, without ajax, if my select menu has 3 items and I add a 4th item and try to submit the form, drupal will give an error saying something similar to "an illegal choice was made, please contact the admin." With ajax this 4th item you created would get saved into the database. So do I have to write validation like if ($select_item > 0 && $select_item <= 3) { //insert into db } Or is there an easier way that will check that the item actually existed in the form array? I'm hoping there is since without ajax, drupal will not submit the form if it was manipulated. Thanks. EDIT: So I basically need this in my callback function? $form_state = array('storage' => NULL, 'submitted' => FALSE); $form_build_id = $_POST['form_build_id']; $form = form_get_cache($form_build_id, $form_state); $args = $form['#parameters']; $form_id = array_shift($args); $form_state['post'] = $form['#post'] = $_POST; $form['#programmed'] = $form['#redirect'] = FALSE; drupal_process_form($form_id, $form, $form_state); To get $_POST['form_build_id'], I sent it as a data param, is that right? Where I use form_get_cache, looks like there is no data. Kind of lost now.

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  • How do I execute queries upon DB connection in Rails?

    - by sycobuny
    I have certain initializing functions that I use to set up audit logging on the DB server side (ie, not rails) in PostgreSQL. At least one has to be issued (setting the current user) before inserting data into or updating any of the audited tables, or else the whole query will fail spectacularly. I can easily call these every time before running any save operation in the code, but DRY makes me think I should have the code repeated in as few places as possible, particularly since this diverges greatly from the ideal of database agnosticism. Currently I'm attempting to override ActiveRecord::Base.establish_connection in an initializer to set it up so that the queries are run as soon as I connect automatically, but it doesn't behave as I expect it to. Here is the code in the initializer: class ActiveRecord::Base # extend the class methods, not the instance methods class << self alias :old_establish_connection :establish_connection # hide the default def establish_connection(*args) ret = old_establish_connection(*args) # call the default # set up necessary session variables for audit logging # call these after calling default, to make sure conn is established 1st db = self.class.connection db.execute("SELECT SV.set('current_user', 'test@localhost')") db.execute("SELECT SV.set('audit_notes', NULL)") # end "empty variable" err ret # return the default's original value end end end puts "Loaded custom establish_connection into ActiveRecord::Base" sycobuny:~/rails$ ruby script/server = Booting WEBrick = Rails 2.3.5 application starting on http://0.0.0.0:3000 Loaded custom establish_connection into ActiveRecord::Base This doesn't give me any errors, and unfortunately I can't check what the method looks like internally (I was using ActiveRecord::Base.method(:establish_connection), but apparently that creates a new Method object each time it's called, which is seemingly worthless cause I can't check object_id for any worthwhile information and I also can't reverse the compilation). However, the code never seems to get called, because any attempt to run a save or an update on a database object fails as I predicted earlier. If this isn't a proper way to execute code immediately on connection to the database, then what is?

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  • How do I determine whether calculation was completed, or detect interrupted calculation?

    - by BenTobin
    I have a rather large workbook that takes a really long time to calculate. It used to be quite a challenge to get it to calculate all the way, since Excel is so eager to silently abort calculation if you so much as look at it. To help alleviate the problem, I created some VBA code to initiate the the calculation, which is initiated by a form, and the result is that it is not quite as easy to interrupt the calculation process, but it is still possible. (I can easily do this by clicking the close X on the form, but I imagine there are other ways) Rather than taking more steps to try and make it harder to interrupt calculation, I'd like to have the code detect whether calculation is complete, so it can notify the user rather than just blindly forging on into the rest of the steps in my code. So far, I can't find any way to do that. I've seen references to Application.CalculationState, but the value is xlDone after I interrupt calculation, even if I interrupt the calculation after a few seconds (it normally takes around an hour). I can't think of a way to do this by checking the value of cells, since I don't know which one is calculated last. I see that there is a way to mark cells as "dirty" but I haven't been able to find a way to check the dirtiness of a cell. And I don't know if that's even the right path to take, since I'd likely have to check every cell in every sheet. The act of interrupting calculation does not raise an error, so my ON ERROR doesn't get triggered. Is there anything I'm missing? Any ideas? Any ideas?

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  • Image Resizing and Compression

    - by GSTAR
    Hi guys, I'm implementing an image upload facility for my website. The uploading facility is complete but what I'm working on at the moment is manipulating the images. For this task I am using PHPThumb (http://phpthumb.gxdlabs.com). Anyway as I go along I'm coming across potential issues, to do with resizing and compression. Basically I want to acheive the following results: The ideal image dimensions are: 800px width, 600px height. If an uploaded image exceeds either of these dimensions, it will need be resized to meet the requirements. Otherwise, leave as it is. The ideal file size is 200kb. If an uploaded image exceeds this then it will need to be compressed to meet this requirement. Otherwise, leave as it is. So in a nutshell: 1) Check the dimensions, resize if required. 2) Check the filesize, compress if required. Has anybody done anything like this / could you give me some pointers? Is PHPThumb the correct tool to do this in?

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  • Testing paginated UIScrollView on iPad

    - by Piotr Czapla
    I'm creating a magazine reader (something like iGizmo on iPad). I have two scrollviews one that paginate over articles and second to paginate inside of an article through pages. I'd like to check memory usage of my app after scrolling through 20 pages. To do so I decided to create an automated ui test that scrolls 20 times right and the check the memory foot print at the end of the test. I need that info to have some metrics before I start optimizing the memory usage And Here is the thing: I can't make the ui automation to pass to the second page. My automation code looks like that: var window = UIATarget.localTarget().frontMostApp().mainWindow(); var articleScrollView = window.scrollViews()[0]; articleScrollView.scrollRight(); // do you know any command to wait until first scrolls ends? articleScrollView.scrollRight(); // this one doesn't work I guess that I need to wait for the first scorlling to end before I can run another one, but I don't know how to do that as each page is just an image. (I don't have anything else on pages yet) Any idea?

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  • Extending a form field to add new validations.

    - by duallain
    I've written an app that uses forms to collect information that is then sent in an email. Many of these forms have a filefield used to attach files to the email. I'd like to validate two things, the size of the file (to ensure the emails are accepted by our mail server. I'd also like to check the file extension, to discourage attaching file types not useable for our users. (This is the python class I'm trying to extend) class FileField(Field): widget = FileInput default_error_messages = { 'invalid': _(u"No file was submitted. Check the encoding type on the form."), 'missing': _(u"No file was submitted."), 'empty': _(u"The submitted file is empty."), 'max_length': _(u'Ensure this filename has at most %(max)d characters (it has %(length)d).'), } def __init__(self, *args, **kwargs): self.max_length = kwargs.pop('max_length', None) super(FileField, self).__init__(*args, **kwargs) def clean(self, data, initial=None): super(FileField, self).clean(initial or data) if not self.required and data in EMPTY_VALUES: return None elif not data and initial: return initial # UploadedFile objects should have name and size attributes. try: file_name = data.name file_size = data.size except AttributeError: raise ValidationError(self.error_messages['invalid']) if self.max_length is not None and len(file_name) > self.max_length: error_values = {'max': self.max_length, 'length': len(file_name)} raise ValidationError(self.error_messages['max_length'] % error_values) if not file_name: raise ValidationError(self.error_messages['invalid']) if not file_size: raise ValidationError(self.error_messages['empty']) return data

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  • Problem with multiple checkbox

    - by Pushpendra
    I am using a checkbox that has the name selectedids[], and I am trying to select all checkbox with the JavaScript but the code is not working. However, when I change the name of checkbox to selectedids it works but I can't do so because I need all the ids that are selected on the POSTED page. The checkbox is as follow. foreach($rows as $row) { <input type="checkbox" name="selectedids[]" value="<?php echo $row['id']; ?>" class="checkbox" /> ........ ........ } And the Java-script function is as follow function SetAllCheckBoxes(CheckValue) { var CheckValue=true; if(!document.forms['main']) return; var objCheckBoxes = document.forms['main'].elements['selectedids[]']; if(!objCheckBoxes) return; var countCheckBoxes = objCheckBoxes.length; if(!countCheckBoxes) objCheckBoxes.checked = CheckValue; else // set the check value for all check boxes for(var i = 0; i < countCheckBoxes; i++) objCheckBoxes[i].checked = CheckValue; } Please help me. Thanks in advance..

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  • csv file upload and update mysql db

    - by Indra
    I am very to new to php. i am using the following code to open a csv file and update my database. i need to check the value of first row-first column of the csv file. if it is matching "some text 1", then i need to run code1, if it is "some text 2", run code2, else code3. I can use if else condition but since i am using while loop It fails. Can anyone help me. $handle = fopen($file_tmp,"r"); while(($fileop = fgetcsv($handle,",")) !== false) { // I need to check here $companycode = mysql_real_escape_string($fileop[0]); $Item = mysql_real_escape_string($fileop[3]); $pack = preg_replace('/[^A-Za-z0-9\. -]/', '', $fileop[4]); $lastmonth = mysql_real_escape_string($fileop[5]); $ltlmonth = mysql_real_escape_string($fileop[6]); $op = mysql_real_escape_string($fileop[9]); $pur = mysql_real_escape_string($fileop[10]); $sale = mysql_real_escape_string($fileop[12]); $bal = mysql_real_escape_string($fileop[17]); $bval = mysql_real_escape_string($fileop[18]); $sval = mysql_real_escape_string($fileop[19]); $sq1 = mysql_query("INSERT INTO `sas` (companycode,Item,pack,lastmonth,ltlmonth,op,pur,sale,bal,bval,sval) VALUES ('$companycode','$Item','$pack','$lastmonth','$ltlmonth','$op','$pur','$sale','$bal','$bval','$sval')"); }

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  • How to create a separate thread to do some operation periodically and update UI in WPF?I'm stack

    - by black sensei
    Hello Experts! I'm trying to do a periodic separated thread operation let's say check for internet connection or check for user's info via web service and update the user interface. i've tried with quartz.net to implement that.So i created an inner class for the window i need to update.That inner class does what is meant for but the problem is that i don't know how to access parent's(window class) members form the child(inner class). for example public partial class Window2 : Window { private int i; public Window2() { InitializeComponent(); } public string doMyOperation() { //code here return result; } public class Myclass :IJob { public void Execute(JobExecutionContext context) { string result = doMyOperation(); //Now here i could be able to call a label of name lblNotif //lblNotif.Content = result; } } } Well the whole idea works but i'm stacked at here i need to access a controls of Window2 Since i'm stacked i tried Spring.Net way of implementing Quartz hoping that i could use MethodInvokingJobDetailFactoryObject and rather have the Operation done on Window2 itself.But for some reason i'm having an exception Cannot resolve type [System.Windows.Window2,System.Windows];, could not load type from string value System.Windows.Window2,System.Windows and the wiring is done so <object name="UpdateLabelJob" type="System.Windows.Window2,System.Windows"/> What i'm i doing wrong here?Is that a way round? thanks for reading and for helping out

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  • UpdateModelFromDatabaseException when trying to add a table to Entity Framework model

    - by Agent_9191
    I'm running into a weird issue with Entity Framework in .NET 3.5 SP1 within Visual Studio 2008. I created a database with a few tables in SQL Server and then created the associated .edmx Entity Framework model and had no issues. I then created a new table in the database that has a foreign key to an existing table and needed to be added to the .edmx. So I opened the .edmx in Visual Studio and in the models right-clicked and chose "Update Model From Database...". I saw the new table in the "add" tab, so I checked it and clicked finish. However I get an error message with the following text: --------------------------- Microsoft Visual Studio --------------------------- An exception of type 'Microsoft.Data.Entity.Design.Model.Commands.UpdateModelFromDatabaseException' occurred while attempting to update from the database. The exception message is: 'Cannot update from the database. Cannot resolve the Name Target for ScalarProperty 'ID <==> CustomerID'.'. --------------------------- OK --------------------------- For reference, here's the tables seem to be the most pertinent to the error. CustomerPreferences already exists in the .edmx. Diets is the table that was added afterwards and trying to add to the .edmx. CREATE TABLE [dbo].[CustomerPreferences]( [ID] [uniqueidentifier] NOT NULL, [LastUpdatedTime] [datetime] NOT NULL, [LastUpdatedBy] [uniqueidentifier] NOT NULL, PRIMARY KEY CLUSTERED ( [ID] ASC )WITH (PAD_INDEX = OFF, STATISTICS_NORECOMPUTE = OFF, IGNORE_DUP_KEY = OFF, ALLOW_ROW_LOCKS = ON, ALLOW_PAGE_LOCKS = ON) ON [PRIMARY] ) ON [PRIMARY] CREATE TABLE [dbo].[Diets]( [ID] [uniqueidentifier] NOT NULL, [CustomerID] [uniqueidentifier] NOT NULL, [Description] [nvarchar](50) NOT NULL, [LastUpdatedTime] [datetime] NOT NULL, [LastUpdatedBy] [uniqueidentifier] NOT NULL, PRIMARY KEY CLUSTERED ( [ID] ASC )WITH (PAD_INDEX = OFF, STATISTICS_NORECOMPUTE = OFF, IGNORE_DUP_KEY = OFF, ALLOW_ROW_LOCKS = ON, ALLOW_PAGE_LOCKS = ON) ON [PRIMARY] ) ON [PRIMARY] GO ALTER TABLE [dbo].[Diets] WITH CHECK ADD CONSTRAINT [FK_Diets_CustomerPreferences] FOREIGN KEY([CustomerID]) REFERENCES [dbo].[CustomerPreferences] ([ID]) GO ALTER TABLE [dbo].[Diets] CHECK CONSTRAINT [FK_Diets_CustomerPreferences] GO This seems like a fairly common use case, so I'm not sure where I'm going wrong.

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  • Recommended approach for error handling with PHP and MYSQL

    - by iama
    I am trying to capture database (MYSQL) errors in my PHP web application. Currently, I see that there are functions like mysqli_error(), mysqli_errno() for capturing the last occurred error. However, this still requires me to check for error occurrence using repeated if/else statements in my php code. You may check my code below to see what I mean. Is there a better approach to doing this? (or) Should I write my own code to raise exceptions and catch them in one single place? What is the recommended approach? Also, does PDO raise exceptions? Thanks. function db_userexists($name, $pwd, &$dbErr) { $bUserExists = false; $uid = 0; $dbErr = ''; $db = new mysqli(SERVER, USER, PASSWORD, DB); if (!mysqli_connect_errno()) { $query = "select uid from user where uname = ? and pwd = ?"; $stmt = $db->prepare($query); if ($stmt) { if ($stmt->bind_param("ss", $name, $pwd)) { if ($stmt->bind_result($uid)) { if ($stmt->execute()) { if ($stmt->fetch()) { if ($uid) $bUserExists = true; } } } } if (!$bUserExists) $dbErr = $db->error(); $stmt->close(); } if (!$bUserExists) $dbErr = $db->error(); $db->close(); } else { $dbErr = mysqli_connect_error(); } return $bUserExists; }

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  • how to make condition on selection of checkbox in user controler

    - by kumar
    I have a user control <input id="check" type="checkbox" /> <label>&nbsp;</label> <fieldset class="clearfix" id="fieldset-exception"> <legend>Student Information</legend> <div class="fiveper"> <label for="StudentID"> Exception ID: <span><%=Html.EditorFor(x => x.studentid)%></span> </label> <label for="Classroom"> Origination: <span><%=Html.EditorFor(model => model.Classroom)%></span> </label> <label for="Subject"> Age: <span><%=Html.EditorFor(model => model.subject)%></span> </label> </div> $('#btnAll').click(function() { $('#Details input[type=checkbox]').attr('checked', 'checked'); }); I am checking all checkboxes using above code but I need to make condition here that user need to select atleast one checkbox to do something? i have other button to go other page based on this checkbox checked? can anybody tell me how to check that and how to make that condition here? Thanks thanks

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  • Why does this sql statement keep saying it is a boolean and not a paramter? (php/Mysql)

    - by ggfan
    In this statement, I am trying to see if there if the latest posting in the database that has the exact same title, price, city, state, detail. If there is, then it would say to the user that the exact post has been already made; if not then insert the posting into the dbc. (This is one type of check so that users can't accidentally post twice. This may not be the best check, but this statement error is annoying me, so I want it to work :)) Why won't this sql work? I think it's not letting the title=$title and not getting the value in the $title... ERROR: mysqli_num_rows() expects parameter 1 to be mysqli_result, boolean given in postad.php on line 365 //there is a form that users fill out that has title, price, city, etc <form> blah blah </form> //if users click submit, then does all the checks and if all okay, insert to dbc if (isset($_POST['submit'])) { // Grab the pposting data from the POST and gets rid of any funny stuff $title = mysqli_real_escape_string($dbc, trim($_POST['title'])); $price = mysqli_real_escape_string($dbc, trim($_POST['price'])); $city = mysqli_real_escape_string($dbc, trim($_POST['city'])); $state = mysqli_real_escape_string($dbc, trim($_POST['state'])); $detail = mysqli_real_escape_string($dbc, trim($_POST['detail'])); if (!is_numeric($price) && !empty($price)) { echo "<p class='error'>The price can only be numbers. No special characters, etc</p>"; } //Error problem...won't let me set title=$title, detail=$detail, etc. //this statement after all the checks so that none of the variables are empty $query="Select * FROM posting WHERE user_id={$_SESSION['user_id']} AND title=$title AND price=$price AND city=$city AND state=$state AND detail=$detail"; $data = mysqli_query($dbc, $query); if(mysqli_num_rows($data)==1) { echo "You already posted this ad. Most likely caused by refreshing too many times."; } }

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  • Why do I need to give my options a value attribute in my dropdown? JQuery related.

    - by Alex
    So far in my web developing experiences, I've noticed that almost all web developers/designers choose to give their options in a select a value like so: <select name="foo"> <option value="bar">BarCheese</option> // etc. // etc. </select> Is this because it is best practice to do so? I ask this because I have done a lot of work with jQuery and dropdown's lately, and sometimes I get really annoyed when I have to check something like: $('select[name=foo]').val() == "bar"); To me, many times that seems less clear than just being able to check the val() against BarCheese. So why is it that most web developers/designers specify a value paramater instead of just letting the options actual value be its value? And yes, if the option has a value attribute I know I can do something like this: $('select[name=foo] option:contains("BarCheese")').attr('selected', 'selected'); But I would still really like to know why this is done. Thanks!!

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  • Detect modification of variable at runtime in C/C++

    - by YuppieNetworking
    Hello, I am developing a library in C++ where users/programmer will extend a class BaseClass that has a method initArray. This method should be implemented by the user/programmer and it should normally initialize all elements of the array m_arr. Here is a snipplet, modified to this example: class BaseClass { public: BaseClass(int n) { m_arr = new double[n]; size = n; }; virtual ~BaseClass(); int size; double* m_arr; virtual int initArray(); }; Sometimes, the user/programmer implements a initArray that does not initialize some elements of m_arr. What I would like is to create a function in my library that checks if initArray did initialize all elements of m_arr. This function should be called by a sanity-check rutine at runtime. My question: is it possible to detect changes on this array? I can only think of initializing the array with some invalid values (like NaN or Inf), call initArray and check that all values have changed. Thanks for your ideas, David

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  • cURL Affects Cookie Retrieval in PHP?

    - by CJ
    I'm not sure if I'm asking this properly. I have two PHP pages located on the same server. The first PHP page sets a cookie with an expiration and the second one checks to see if that cookie was set. if it is set, it returns "on". If it isn't set, it returns "off". If I just run the pages like "www.example.com/set_cookie.php" AND "www.example.com/is_cookie_set.php" I get an "on" from is_cookie_set.php. Heres the problem, on the set_cookie.php file I have a function called is_set. This function executes the following cURL and returns the contents ("on" or "off"). Unfortunately, the contents are always returned as "off". however, if I check the file manually ("www.example.com/is_cookie_set.php") I can see that the cookie was set. Heres the function : <?php function is_set() { $ch = curl_init(); curl_setopt($ch, CURLOPT_URL, 'http://example.com/is_cookie_set.php'); curl_setopt($ch, CURLOPT_RETURNTRANSFER, 1); $contents = curl_exec ($ch); curl_close ($ch); echo $contents; } ?> Please note, I'm not using cURL to GET or SET cookies, only to check a page that checks if the cookie was set. I've looked into CURLOPT_COOKIEJAR, and CURLOPT_COOKIEFILE, but I believe those are for setting cookies via cURL and I don't want to do this.

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  • How to give user confirmation message before ActionLink based on validation

    - by RememberME
    I have the following link. On click, I'd like to check the item.primary_company field and if populated, give the user a warning and ask if they would like to continue. How can I do this? <a href="<%= Url.Action("Activate", new {id = item.company_id}) %>" class="fg=button fg-button-icon-solo ui-state-default ui-corner-all"><span class="ui-icon ui-icon-refresh"></span></a> EDIT I've changed to this, but nothing happens when clicked. Also, I don't know how to reference the item to do the check on the primary_company field. I only want to message to show if item.primary_company.HasValue. I'd also like to show item.company1.company_name in the confirm message. <a href="#" onclick="return Actionclick("<%= Url.Action("Activate", new {id = item.company_id}) %>");" class="fg=button fg-button-icon-solo ui-state-default ui-corner-all"><span class="ui-icon ui-icon-refresh"></span></a> <script type="text/javascript"> function Actionclick(url) { alert("myclick"); if ( confirm("Do you want to activate this company's primary company and all other subsidiaries?")) { location.href(url); } }; </script>

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  • Is it not possible to make a C++ application "Crash Proof"?

    - by Enno Shioji
    Let's say we have an SDK in C++ that accepts some binary data (like a picture) and does something. Is it not possible to make this SDK "crash-proof"? By crash I primarily mean forceful termination by the OS upon memory access violation, due to invalid input passed by the user (like an abnormally short junk data). I have no experience with C++, but when I googled, I found several means that sounded like a solution (use a vector instead of an array, configure the compiler so that automatic bounds check is performed, etc.). When I presented this to the developer, he said it is still not possible.. Not that I don't believe him, but if so, how is language like Java handling this? I thought the JVM performs everytime a bounds check. If so, why can't one do the same thing in C++ manually? UPDATE By "Crash proof" I don't mean that the application does not terminate. I mean it should not abruptly terminate without information of what happened (I mean it will dump core etc., but is it not possible to display a message like "Argument x was not valid" etc.?)

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  • short-cutting equality checking in F#?

    - by John Clements
    In F#, the equality operator (=) is generally extensional, rather than intensional. That's great! Unfortunately, it appears to me that F# does not use pointer equality to short-cut these extensional comparisons. For instance, this code: type Z = MT | NMT of Z ref // create a Z: let a = ref MT // make it point to itself: a := NMT a // check to see whether it's equal to itself: printf "a = a: %A\n" (a = a) ... gives me a big fat segmentation fault[*], despite the fact that 'a' and 'a' both evaluate to the same reference. That's not so great. Other functional languages (e.g. PLT Scheme) get this right, using pointer comparisons conservatively, to return 'true' when it can be determined using a pointer comparison. So: I'll accept the fact that F#'s equality operator doesn't use short-cutting; is there some way to perform an intensional (pointer-based) equality check? The (==) operator is not defined on my types, and I'd love it if someone could tell me that it's available somehow. Or tell me that I'm wrong in my analysis of the situation: I'd love that, too... [*] That would probably be a stack overflow on Windows; there are things about Mono that I'm not that fond of...

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  • Programming logic best practice - redundant checks

    - by eldblz
    I'm creating a large PHP project and I've a trivial doubt about how to proceed. Assume we got a class books, in this class I've the method ReturnInfo: function ReturnInfo($id) { if( is_numeric($id) ) { $query = "SELECT * FROM books WHERE id='" . $id . "' LIMIT 1;"; if( $row = $this->DBDrive->ExecuteQuery($query, $FetchResults=TRUE) ) { return $row; } else { return FALSE; } } else { throw new Exception('Books - ReturnInfo - id not valid.'); } } Then i have another method PrintInfo function PrintInfo($id) { print_r( $this->ReturnInfo($id) ); } Obviously the code sample are just for example and not actual production code. In the second method should I check (again) if id is numeric ? Or can I skip it because is already taken care in the first method and if it's not an exception will be thrown? Till now I always wrote code with redundant checks (no matter if already checked elsewhere i'll check it also here) Is there a best practice? Is just common sense? Thank you in advance for your kind replies.

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  • Could this be considered a well-written class (am I using OOP correctly)?

    - by Ben Dauphinee
    I have been learning OOP principals on my own for a while, and taken a few cracks at writing classes. What I really need to know now is if I am actually using what I have learned correctly, or if I could improve as far as OOP is concerned. I have chopped a massive portion of code out of a class that I have been working on for a while now, and pasted it here. To all you skilled and knowledgeable programmers here I ask: Am I doing it wrong? class acl extends genericAPI{ // -- Copied from genericAPI class protected final function sanityCheck($what, $check, $vars){ switch($check){ case 'set': if(isset($vars[$what])){return(1);}else{return(0);} break; } } // --------------------------------- protected $db = null; protected $dataQuery = null; public function __construct(Zend_Db_Adapter_Abstract $db, $config = array()){ $this->db = $db; if(!empty($config)){$this->config = $config;} } protected function _buildQuery($selectType = null, $vars = array()){ // Removed switches for simplicity sake $this->dataQuery = $this->db->select( )->from( $this->config['table_users'], array('tf' => '(CASE WHEN count(*) > 0 THEN 1 ELSE 0 END)') )->where( $this->config['uidcol'] . ' = ?', $vars['uid'] ); } protected function _sanityRun_acl($sanitycheck, &$vars){ switch($sanitycheck){ case 'uid_set': if(!$this->sanityCheck('uid', 'set', $vars)){ throw new Exception(ERR_ACL_NOUID); } $vars['uid'] = settype($vars['uid'], 'integer'); break; } } private function user($action = null, $vars = array()){ switch($action){ case 'exists': $this->_sanityRun_acl('uid_set', $vars); $this->_buildQuery('user_exists_idcheck', $vars); return($this->db->fetchOne($this->dataQuery->__toString())); break; } } public function user_exists($uid){ return($this->user('exists', array('uid' => $uid))); } } $return = $acl_test->user_exists(1);

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  • How to determine if a target will be executed?

    - by Scott Langham
    Hi, I'm writing an msbuild file and have something like this: <ValidateDependsOn>$(ValidateDependsOn);ValidateA</ValidateDependsOn> <ValidateDependsOn>$(ValidateDependsOn);ValidateB</ValidateDependsOn> <Target Name="BuildA"> <!-- stuff --> </Target> <Target Name="BuildB"> <!-- stuff --> </Target> <Target Name="ValidateA"> <Error /> <!-- check properties and machine environment are suitable to run BuildA --> </Target> <Target Name="ValidateB"> <Error /> <!-- check properties and machine environment are suitable to run BuildB --> </Target> Builds can take a while. Originally we had the Build steps depending on the Validate steps, but sometimes a validate step wouldn't run until the middle of the build and you would have wasted time getting there. So, we moved the validate steps to the start by using the ValidateDependsOn pattern to insert the targets to run up front. The problem now though is that sometimes during a build BuildB may not actually run, and this means I don't need and in fact, don't want ValidateB to run. Is there any way I can selectively update ValidateDependsOn by conditionally knowing which targets will actually be run? I'm looking for something equivalent to: <ValidateDependsOn Condition="TargetWillRun(BuildB)">$(ValidateDependsOn);ValidateB</ValidateDependsOn>

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  • jQuery: Preventing an event from being attached more than once?

    - by Evan Carroll
    Essentially, I have an element FOO that I want when clicked to attach a click event to a completely separate set of elements BAR, so that when they're clicked they can revert FOO to its previous content. I only want this event attached once. When FOO is clicked, its content is cached away in $back_up, and a trigger is added on the BAR set so that when clicked they can revert FOO back to its previous state. Is there a clever way to do this? Like to only .bind() if the event doesn't already exist? $('<div class="noprint little check" />').click( function () { var $warranty_explaination = $(this).closest('.page').children('.warranty_explaination'); var $back_up = $warranty_explaination.clone(true); $(this).closest('.page').find('.warranties .check:not(.noprint)').click( function () { /* This is the code I don't want to fire more than once */ /*, I just want it to be set to whatever is in the $back_up */ alert('reset'); $warranty_explaination.replaceWith( $back_up ) } ); $warranty_explaination.html('asdf') } ) Currently, the best way I can think to do this is to attach a class, and select where that class doesn't exist.

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