Search Results

Search found 7722 results on 309 pages for 'pitfalls to avoid'.

Page 202/309 | < Previous Page | 198 199 200 201 202 203 204 205 206 207 208 209  | Next Page >

• PHP 5.3 Namespaces should i use every PHP function with backslash?

  - by lhwparis

  Hi, im now using namespaces in PHP 5.3 now there is a fallback mechanism for functions which dont exist in the namespace. so php every time checks if the function exists in namespace and then tries to load it from global space. So what about all php internal functions? strstr for example? Should i now use every php internal function with a \ ? to avoid php first checking the namespace? is this fallback a huge performance drop? what do you think?

  Read the article

• WPF Logical Tree - bottom up vs. top down

  - by Dor Rotman

  Hello, I've read the MSDN article about the layouts pass, that states: When a node is added or removed from the logical tree, property invalidations are raised on the node's parent and all its children. As a result, a top-down construction pattern should always be followed to avoid the cost of unnecessary invalidations on nodes that have already been validated. Now lets assume I do this. Won't the users see the control tree populate itself and the layout change several times during the control creation process? I want the whole control tree to just appear completely full. Thanks!

  Read the article

• Why can't I enforce derived classes to have parameterless constructors?

  - by FrisbeeBen

  I am trying to do the following: public class foo<T> where T : bar, new() { public foo() { _t = new T(); } private T _t; } public abstract class bar { public abstract void someMethod(); // Some implementation } public class baz : bar { public overide someMethod(){//Implementation} } And I am attempting to use it as follows: foo<baz> fooObject = new foo<baz>(); And I get an error explaining that 'T' must be a non-abstract type with a public parameterless constructor in order to use it as parameter 'T' in the generic type or method. I fully understand why this must be, and also understand that I could pass a pre-initialized object of type 'T' in as a constructor argument to avoid having to 'new' it, but is there any way around this? any way to enforce classes that derive from 'bar' to supply parameterless constructors?

  Read the article

• How Do I Execute A Stored Procedure From A BizTalk SendPort?

  - by kgarske

  Hello, I would like to call a stored procedure from a SendPort. I want to avoid an orchestration and instead, create a subscription to the message box based on the receive port and message type. I also need to use attributes from the received message xml as parameters for my stored procedure. My assumption is that I should use WCF-SQL adapter. However, the only examples I have found require a 20 step process and some magic/luck... oh yeah, and an orchestration. Am I crazy for thinking this should be way simpler than it seems? Can anyone provide me with resources or advice?

  Read the article

• Is there a way to test if a scalar has been stringified or not?

  - by Yobert

  I am writing a thing to output something similar to JSON, from a perl structure. I want the quoting to behave like this: "string" outputs "string" "05" outputs "05" "5" outputs "5" 5 outputs 5 05 outputs 5, or 05 would be acceptable JSON::XS handles this by testing if a scalar has been "stringified" or not, which I think is very cool. But I can't find a way to do this test myself without writing XS, which I'd rather avoid. Is this possible? I can't find this anywhere on CPAN without finding vast pedantry about Scalar::Util::looks_like_number, etc which completely isn't what I want. The only stopgap I can find is Devel::Peek, which feels evil. And also, just like JSON::XS, I'm fine with this secenario: my $a = 5; print $a."\n"; # now $a outputs "5" instead of 5)

  Read the article

• Log4Perl - how to set exit code if any WARN, ERROR, or FATAL messages?

  - by pdxrlk

  Hi - I've been using Log4Perl extensively in a number of scripts. I'd like to augment those scripts to set an error code if any WARN or ERROR messages have been logged. I couldn't find any obvious way to do this based on existing documentation. I'd like to avoid a brute-force rewrite of my existing scripts to add a check on every WARN or ERROR log message; I'd prefer to handle it prior to script exit if possible like this pseudocode: if $log->has_warnings_or_errors then exit 1 else exit 0 Is there any easy way to call Log4Perl to determine if the current logger has issues messages of certain levels? Thanks.

  Read the article

• Singleton wrapper for Context

  - by kpdvx

  I'm considering creating a singleton wrapper for a Context so my model objects, if necessary, can open and read from a database connection. My model objects do not have access to a Context, and I'd like to avoid needing to pass a reference to a Context from object to object. I was planning to place into this singleton a reference to the Context returned by Application.getApplicationContext(). This singleton object would be initialized in my custom Application instance before anything else would need to or have a chance to use it. Can anyone think of a reason to not do this?

  Read the article

• Why do I have to give an identifier?

  - by Knowing me knowing you

  In code: try { System.out.print(fromClient.readLine()); } catch(IOException )//LINE 1 { System.err.println("Error while trying to read from Client"); } In code line marked as LINE 1 compiler forces me to give an identifier even though I'm not using it. Why this unnatural constrain? And then if I type an identifier I'm getting warning that identifier isn't used. It just doesn't make sense to me, forcing a programmer to do something unnecesarry and surplus. And after me someone will revise this code and will be wondering if I didn't use this variable on purpouse or I just forgot. So in order to avoid that I have to write additional comment explaining why I do not use variable which is unnecessary in my code. Thanks

  Read the article

• Is it bad practice to initialize a variable to a dummy value?

  - by froadie

  This question is a result of the answers to this question that I just asked. It was claimed that this code is "ugly" because it initializes a variable to a value that will never be read: String tempName = null; try{ tempName = buildFileName(); } catch(Exception e){ ... System.exit(1); } FILE_NAME = tempName; Is this indeed bad practice? Should one avoid initializing variables to dummy values that will never actually be used? (EDIT - And what about initializing a String variable to "" before a loop that will concatenate values to the String...? Or is this in a separate category? e.g. String whatever = ""; for(String str : someCollection){ whatever += str; } )

  Read the article

• populate a treeview with xml file using c#

  - by syedsaleemss

  Im using c#.net windows form application. I have an xml file that contains nodes. I need to populate a treeview with the nodes present in the xml file. Also avoid repeated node names. For this my idea is while populating the treeview, copy the node names into a list and there see if the node already exits. If it already exits, go to the next node else display it. List listOfNodes = new List(); listOfNodes.Add(xNode.Name.ToString()); //if (!(listOfNodes.Contains(xNode.Name.ToString()))) I was trying with this. but Im unable to do. Please suggest me with a proper code.

  Read the article

• Help getting PHP sessions to persist after being taken off-site

  - by Rob

  Hi, we're working on a payment gateway system with PHP. We use sessions to store the shopping cart data. The system takes you off-site to the payment processor's site, and then return you to your site. On most hosts, we have no issues when we arrive back at our site and having the session data still be there. On those with an issue, turning off the PHP session referer_check has worked in the past. We don't really want to have to include the PHPSESSID as a GET variable, and hope to avoid that. What I'm looking for is what other server configurations would cause the session to be killed, and any other workarounds there might be. Thanks for your help.

  Read the article

• CSS: reposition element on hover state but maintain clickable area position

  - by abirduphigh

  I'm trying to create the effect of a button that 'lifts' from the page when rolled over. Using CSS, I have a block style <a> element that, when hovered, re-positions itself up and to the left 5px, and a shadow is left behind: a { display: inline-block; position: relative; } a:hover { top: -5px; left: -5px; box-shadow: rgba(0,0,0,.2) 5px 5px 2px; } The problem: When the <a> block jumps 5px away from the cursor during the hover, the cursor is no longer actually hovering over the block and the block then jumps back when the cursor is moved only slightly thereafter. How can I maintain the original hover area so that the element doesn't keep jumping back and forth when the cursor is only slightly moved? I'd like to avoid adding superfluous container elements to my code if at all possible.

  Read the article

• Any idea why this query always returns duplicate items?

  - by Kardo

  I want to get all Images not used by current ItemID. The this subquery but it also always returns duplicate Images: EDITED select Images.ImageID, Images.ItemStatus, Images.UserName, Images.Url, Image_Item.ItemID, Image_Item.ItemID from Images left join (select ImageID, ItemID, MAX(DateCreated) x from Image_Item where ItemID != '5a0077fe-cf86-434d-9f3b-7ff3030a1b6e' group by ImageID, ItemID having count(*) = 1) image_item on Images.imageid = image_item.imageid where ItemID is not null I guess the problem is with the subquery which I can't avoid duplicate rows: select ImageID, ItemID, MAX(DateCreated) x from Image_Item where ItemID != '5a0077fe-cf86-434d-9f3b-7ff3030a1b6e' group by ImageID, ItemID having count(*) = 1 Result: F2EECBDC-963D-42A7-90B1-4F82F89A64C7 0578AC61-3C32-4A1D-812C-60A09A661E71 F2EECBDC-963D-42A7-90B1-4F82F89A64C7 9A4EC913-5AD6-4F9E-AF6D-CF4455D81C10 42BC8B1A-7430-4915-9CDA-C907CBC76D6A CB298EB9-A105-4797-985E-A370013B684F 16371C34-B861-477C-9A7C-DEB27C8F333D 44E6349B-7EBF-4C7E-B3B0-1C6E2F19992C Table: Images ImageID uniqueidentifier UserName nvarchar(100) DateCreated smalldatetime Url nvarchar(250) ItemStatus char(1) Table: Image_Item ImageID uniqueidentifier ItemID uniqueidentifier UserName nvarchar(100) ItemStatus char(1) DateCreated smalldatetime Any kind help is highly appreciated.

  Read the article

• Should I put a try-finally block after every Object.Create?

  - by max

  I have a general question about best practice in OO Delphi. Currently, I put try-finally blocks anywhere I create an object to free that object after usage (to avoid memory leaks). E.g.: aObject := TObject.Create; try aOBject.AProcedure(); ... finally aObject.Free; end; instead of: aObject := TObject.Create; aObject.AProcedure(); .. aObject.Free; Do you think it is good practice, or too much overhead? And what about the performance?

  Read the article

• How to know if the website being scraped has changed?

  - by Lost_in_code

  I'm using PHP to scrape a website and collect some data. It's all done without using regex. I'm using php's explode() method to find particular HTML tags instead. It is possible that if the structure of the website changes (CSS, HTML), then wrong data may be collected by the scraper. So the question is - how do I know if the HTML structure has changed? How to identify this before storing any data to my database to avoid wrong data being stored.

  Read the article

• Activity.findViewById returning null sporadically

  - by adstro

  From the crash logs that I am getting from the Android market, I can see that some of my users are getting Force Closes caused by NullPointerExceptions when my code tries to access views that are in my application. In one example, my activity makes a call to findViewById() in onCreate() after I call setContentView(). I get an NPE when I try to access the view after the call to findViewById() (still in onCreate). What has me really scratching my head is that this does not happen all of the time (in fact most of the time the code acts as I would expect), but enough to have me concerned. I could add code to always check for null and avoid the NPE, but I would like to understand what could be causing the sporadic behavior. Does anyone know what could be causing this?

  Read the article

• Proper use of of typedef in C++

  - by dicroce

  I have coworkers who occasionally use typedef to avoid typing. For example: typedef std::list<Foobar> FoobarList; ... FoobarList GetFoobars(); Personally, I always hate coming across code like this, largely because it forces me to go lookup the typedef so I can tell how to use it. I also feel like this sort of thing is a potential slippery slope... If you do this, why aren't you doing it more? (pretty soon, your code is totally obfuscated). I found this SO question regarding this issue: when should I use typedef in C I have two questions: 1) am I truly alone in disliking this? 2) If the vast majority of people think this sort of typedef use is OK, what criteria do you use to determine whether to typedef a type?

  Read the article

• jQuery resize event for div children

  - by Frank Michael Kraft

  $("div.content-left > *, div.content-main > *" ).live('resize',function(){alert("Size changed")}); does not work, because the resize event only applies to window resizes. But in my case the divs change size late, because the content is loaded late by an ajax request - or by clicking a panel menu. I definatley need to avoid to register on all individual events of the children (ajax, click), because that can be very many different events and then it is not maintainable.

  Read the article

• maintain formatting entered into an html form?

  - by NickG77

  Im setting up a web form, and I'm trying to have it where visitors can paste their resumes into a text area. Then I want to email the info using php mail(). But the resume info is just stored in the variable as one long string with no formatting. Is there a way I can send the pasted resume text to the client in the resume format? Maintaining all the line breaks and stuff? He wants to avoid having people upload resumes.

  Read the article

• How can I double-enhance a class with cglib?

  - by artemb

  Hi there! Here's the code: Patient patient = factory.createPatient(); Enhancer enhancer = new Enhancer(); enhancer.setSuperclass(patient.getClass()); enhancer.setCallback(new DefaultMethodInterceptor(patient)); patient = (Patient) enhancer.create(); assertThat(patient.getFirstName()).isNotNull(); Enhancer enhancer2 = new Enhancer(); enhancer2.setSuperclass(patient.getClass()); enhancer2.setCallback(new DefaultMethodInterceptor(patient)); patient = (Patient) enhancer2.create(); assertThat(patient.getFirstName()).isNotNull(); It fails on the last assert with net.sf.cglib.core.CodeGenerationException: java.lang.reflect.InvocationTargetException-->null ... Caused by: java.lang.reflect.InvocationTargetException ... Caused by: java.lang.ClassFormatError: Duplicate method name&signature in class file my/package/entity/Patient$$EnhancerByCGLIB$$ca1e6685$$EnhancerByCGLIB$$f52743be I ask this because I want to enhance Hibernate's entities, but sometimes it returns already enhanced ones by itself and my second enhancement fails. How can I avoid this?

  Read the article

• 1120: Why can't it access the variable?

  - by Oden

  I'm new at as3, maybe thats the reason why i don't understand, why the setInterval causes an error. <mx:Script> <![CDATA[ import flash.utils.setInterval; import mx.controls.Alert; [Bindable] public var MyInt:int = 500; setInterval(function():void{ ++MyInt; },1000); ]]> </mx:Script> I have a label where the value of MyInt gets visible, the bind works perfect, i've tested it several ways, and i i create a button it grows the number, but if i use the setInterval function i get an error: Access of undefined property myInt. Why? What does cause this? Please explain it, so I can avoid errors like this. Thanks

  Read the article

• Is it always bad idea to use inline css for used-once property?

  - by user93422

  I have a table, with 10 columns. I want to control the width of each column. Each column is unique, right now I create an external CSS style for each column: div#my-page table#members th.name-col { width: 40px; } I know there is a best practice to avoid inline style. I do approve using external CSS for anything look'n'feel related: fonts, colors, images. But is it really better to use external CSS in this case? It does not incur extra maintenance cost. It is easier to produce. Cons I can think of: If you have separate designers and development team - using inline styles will force designers to modify content-file (aspx in my case). It might use more bandwidth. Anything else I've missed?

  Read the article

• Detect NativeDragDrop to Trash or RecycleBin

  - by colder

  I will let user remove item from List with a cool method. Drag an item in adobe air List control and then drop it to Trash(OSX) or Recycle Bin(Win). The trash accept move drag action only. So I think I must set dragMoveEnable=true. When I drag an item to Recycle Bin on Windows. It show accept effect(alpha mask) and Air remove that object from List's dataProvider. So I can find which one is disappear. But when I drag to Trash on MacOSX. It show effect too. But Air do nothing for List. Maybe this is a bug. How can I avoid it? Are there any way to detect where dropped by user?

  Read the article

• Best way of obfuscating / encrypting form data on the iPhone

  - by cannyboy

  I want to create an app which holds sensitive information (imagine it's bank account details, thought it's not). The user enters this information on a form the first time the app starts up. I want this info to be saved, and available, any time the user uses the app (without having to enter a password). However, if the iPhone has a password lock on it, and is stolen, I don't want the data to be easily accessible from the file system. What is the best way of encrypting or obfuscating the data? There is not a lot of data, just a dozen NSStrings from the UITextFields on the form. I'm aware there are encryption export restrictions on the iPhone for non-US developers (I am in UK), so I would prefer to avoid going jumping through any of Apple's app submission hoops to get it on the store.

  Read the article

• Aptana Open Resource Key Binding

  - by yagudaev

  The default keyboard shortcut for open resource in Eclipse is Ctrl+Shift+R. It is also the case in Aptana, but there also seems to be a conflicting key since when clicked it brings up a context menu with 2 options "Run" and "Open Resource". How to I avoid having this context menu pop up? I tried to go to the preferences and look for conflicting key-bindings but I could not find it. I am also not sure what "Run" command is actually bound (I tried searching based on the key combination, that did not seem to have worked).

  Read the article

< Previous Page | 198 199 200 201 202 203 204 205 206 207 208 209  | Next Page >