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  • GUID.TryParse() ?

    - by Jack Marchetti
    Obviously there is no public GUID.TryParse() in .NET CLR 2.0. So, I was looking into regular expressions [aka googling around to find one] and each time I found one there was a heated argument in the comments section about RegEx A doesn't work, use RegEx B. Then someone would write Regex C yadda yadda So anyway, What I decided to do was this, but I feel bad about it. public static bool IsGuid (string possibleGuid) { try { Guid gid = new Guid(possibleGuid); return true; } catch (Exception ex) { return false; } } Obviously I don't really like this since it's been drilled into me since day one to avoid throwing exceptions if you can defensibly code around it. Does anyonek now why there is no public Guid.TryParse() in the .NET Framework? Does anyone have a real Regular Expression that will work for all GUIDs?

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  • Javascript & jquery : Unable to increment within a form

    - by Daniyal
    I got a simple increment function like this: $(function(){ $("#inc").click(function(){ var value = parseInt($(":text[name='ice_id']").val()) + 1; $(":text[name='ice_id']").val(value); }); $("#dec").click(function(){ var value = parseInt($(":text[name='ice_id']").val()) - 1; $(":text[name='ice_id']").val(value); }); }); the ice_id text field is embedded within a form <form id="masterSubmit" name="masterSubmit" action="" method="post"> <td><input id="ice_id" type="text" name="ice_id" size="16" maxlength="15"></td> </form> When I try now to increment , it successfully increments a number, but shows the following weird behavior: It 'refreshes' the site, so that the content of the text field is gone. This behavior disappears, if I comment out the form tags ...unfortunately the form tags are required for an AJAX-submit. Are there any ways to avoid this problem? Thanks in advance for any hints and best regards Daniyal

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  • How to have NHibernate persist a String.Empty property value as NULL

    - by Todd
    I have a fairly simple class that I want to save to SQL Server via NHibernate (w/ Fluent mappings). The class is made up mostly of optional string fields. My problem is I default the class fields to string.empty to avoid NullRefExceptions and when NHibernate saves the row to the database each column contains an empty string instead of null. Question: Is there a way for me to get NHibernate to automatically save null when the string property is an empty string? Or do I need to litter my code with if (string.empty) checks?

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  • sqrt(int_value + 0.0) ? The point?

    - by Earlz
    Hello, while doing some homework in my very strange C++ book, which I've been told before to throw away, had a very peculiar code segment. I know homework stuff always throws in extra "mystery" to try to confuse you like indenting 2 lines after a single-statement for-loop. But this one I'm confused on because it seems to serve some real-purpose. basically it is like this: int counter=10; ... if(pow(floor(sqrt(counter+0.0)),2) == counter) ... I'm interested in this part especially: sqrt(counter+0.0) Is there some purpose to the +0.0? Is this the poormans way of doing a static cast to a double? Does this avoid some compiler warning on some compiler I do not use? The entire program printed the exact same thing and compiled without warnings on g++ whenever I left out the +0.0 part. Maybe I'm not using a weird enough compiler?

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  • Passing operator as a parameter

    - by nacho4d
    Hi, I want to have a function that evaluates 2 bool vars (like a truth table) for example: since T | F : T then myfunc('t', 'f', ||); /*defined as: bool myfunc(char lv, char rv, ????)*/ should return true; how can I pass the third parameter? (I know is possible to pass it as a char* but then I will have to have another table to compare operator string and then do the operation which is something I would like to avoid) Is it possible to pass an operator like ^(XOR) or ||(OR) or &&(AND), etc in a function/method? Thanks in advance

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  • Unique constraint with nullable column

    - by Álvaro G. Vicario
    I have a table that holds nested categories. I want to avoid duplicate names on same-level items (i.e., categories with same parent). I've come with this: CREATE TABLE `category` ( `category_id` int(10) unsigned NOT NULL AUTO_INCREMENT, `category_name` varchar(100) NOT NULL, `parent_id` int(10) unsigned DEFAULT NULL, PRIMARY KEY (`category_id`), UNIQUE KEY `category_name_UNIQUE` (`category_name`,`parent_id`), KEY `fk_category_category1` (`parent_id`,`category_id`), CONSTRAINT `fk_category_category1` FOREIGN KEY (`parent_id`) REFERENCES `category` (`category_id`) ON DELETE SET NULL ON UPDATE CASCADE ) ENGINE=InnoDB DEFAULT CHARSET=utf8 COLLATE=utf8_spanish_ci Unluckily, category_name_UNIQUE does not enforce my rule for root level categories (those where parent_id is NULL). Is there a reasonable workaround?

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  • Trouble creating a makefile

    - by catia
    Hi everyone! I'm having some trouble making a Makefile. Write now I just compile everything every time. Although, the professor is ok with that, I do want to get it working faster and to avoid unnecessary compiling. Here's what I have. FILES= p6.cpp SetIter.cpp Node.cpp Set.cpp CFLAGS= -ansi -pendantic -Wall -Wextra CC= g++ MakePg6: p6.cpp SetIter.cpp Node.cpp Set.cpp $(CC) $(CFLAGS) $(FILES) -o pg6 Node.cpp - node class Set.cpp - uses nodes. Friend of Node. SetIter.cpp - gets a set and uses a pointer to iterator through I'm confused with some of the depencies arising from the friends thing and the point of lib.o being included in the Makefile as some sites have. Any help is greatly appreciated. Thanks in advance.

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  • Use a ContextLoaderListener in accordance with DispatchServlet

    - by Phuong Nguyen de ManCity fan
    I want to use both ContextLoaderListener (so that I can pass Spring Beans to my servlet) as well as DispatchServlet (Spring MVC). However, currently I have to pass init param to these both class initializer: <param-name>contextConfigLocation</param-name> <param-value> /WEB-INF/spring/app-config.xml </param-value> So, I use the same xml for these both classes. Wonder if it would lead to my beans being initialized twice? If yes, how would I do to avoid that?

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  • Persisting sensitve data in asp.net, odd implementation

    - by rawsonstreet
    For reasons not in scope of this question I have implemented a .net project in an iframe which runs from a classic asp page. The classic asp site persisted a few sensitive values by hitting the db on each page. I have passed there variables as xml to the aspx page, now I need to make these values available on any page of this .net site. I've looked into the cache object but we are on a web farm so I am not sure it would work. Is there a way I can can instantiate an object in a base page class and have other pages inherit from the base page to access these values? What is the best way to persist these values? A few more points to consider the site runs in https mode and I cannot use session variables, and I would like to avoid cookies if possible..

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  • NHibernate SchemaUpdate adding existing foreign keys again?

    - by afsharm
    I'm using SchemaUpdate to synchronize my hbms with existing database. Database has recently created based on hbms and is completely up-to-date. But SchemaUpdate generates all foreign key constraints again. For example suppose you have Student and Teacher. Student has association to Teacher with name ArtTeacher. ArtTeacher is a foreign key from Student to Teacher. Suppose database is up-to-date and currently holde Student, Teacher and their foreign key relation. So HBM and Database are equivalent. Know SchemaUpdate must not do anything but when I see its generated scripts, it re-produce that foreign key again. Why this happens? Is there any way to avoid it?

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  • Android how do I wait until a service is actually connected?

    - by Ryan
    I have an Activity calling a Service defined in IDownloaderService.aidl: public class Downloader extends Activity { IDownloaderService downloader = null; // ... In Downloader.onCreate(Bundle) I tried to bindService Intent serviceIntent = new Intent(this, DownloaderService.class); if (bindService(serviceIntent, sc, BIND_AUTO_CREATE)) { // ... and within the ServiceConnection object sc I did this public void onServiceConnected(ComponentName name, IBinder service) { Log.w("XXX", "onServiceConnected"); downloader = IDownloaderService.Stub.asInterface(service); // ... By adding all kinds of Log.xx I found that the code after if(bindService(...)) actually goes BEFORE ServiceConnection.onServiceConnected is being called - that is, when downloader is still null - which gets me into trouble. All the samples in ApiDemos avoid this timing problem by only calling services when triggered by user actions. But what should I do to right use this service after bindService succeeds? How can I wait for ServiceConnection.onServiceConnected being called reliably?

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  • Refresh combo box in Windows Form VB.NET

    - by fireBand
    Following is the code to populate combobox using DataSource Dim CountryList As Array = MyCtrl.GetAllCountries With cbCountyList .DataSource = CountryList .DisplayMember = "CountryName" .ValueMember = "CountryID" End With After adding a new COuntry Name to Database I want to reflect the changes in combobox. Repeating this code is not an option becasue it triggers SelectIndexChange event and had to do some crappy work around to avoid that. So I was wondering if there is way to refresh the combobox list. I actually thought binding with the DataSource property supposed to do it automatically. I also tried cbCountyList.Refresh() Thanks in advance.

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  • What are the likely main reasons my website is very slow on IE?

    - by Bhupi
    Hi, I need to know what can be the main reasons (apart from the basics like grouping CSS selectors, reducing image size, using image sprite etc.) which makes a website slow on Internet Explorer, because my website works fine on the others like FF, chrome etc. Is it the huge use of Javascript framework (ie. jQuery, extjs, prototype)? Is it because of the use of plugins based on JS framework? Should I use core javascript and remove the use of any js framework? Should I try to avoid using jQuery(document).ready()? in case of jQuery framework? Above some of the questions which I know and please answer the questions which I couldn't ask because of lesser knowledge about these. I need to make my website perform well on IE (6,7,8) also please suggest. Thanks

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  • IntelliJ Split Window Navigation

    - by jmquigley
    If I split the editor window (horizontal or vertical) into N tab groups, how do I switch/toggle from one tab group to another via the keyboard? If all of the tabs are in the same group you can switch from each tab easily (CTRL + right/left arrow), but when they're in separate tab groups I can't. I've searched through the key mappings and have not found one that seems to accomplish this. I know I can use the mouse, but I'm trying to find ways to avoid the mouse and stay with the keyboard. TIA for any help on this.

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  • Appending target="_blank" to links in an iframe without using <body onload>

    - by CincauHangus
    I'm trying to change the links in an iframe to load in a new window instead of the iframe itself. Currently I use this code in head: $(document).ready(function() { var oIFrame = document.getElementById("iframeID"); var oDoc = (oIFrame.contentWindow || oIFrame.contentDocument); if(oDoc.document) oDoc = oDoc.document; var links = oDoc.getElementsByTagName("a"); for(var i=0; i<links.length; i++) { links[i].target="_blank"; } }); However, the code above is triggered before the iframe is fully loaded with its contents. I know this code would work if it's triggered in the body onload attribute, but I'd like to avoid that method and implement it in a function or a file instead.

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  • mysql reference result from subquery

    - by iamrohitbanga
    this is what i am doing update t1 set x=a,y=b where a and b are obtained from (select query here) i know the select query the select query returns multiple results which are the same when i use group by or distinct query execution slows down considerably a and b are forward references so mysql reports an error i want to set a equal to the value obtained in the first row and b equal to the value obtained in the first row for the respective columns, to avoid group by. i don't know how to refer to the first result from the select query. how can i achieve all this?

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  • WebKit gets blank when clicking on the menu toolbar

    - by Miguel Ángel Ortuño
    Hi y'all. I've embebed a WebKit view into a modal dialog using Carbon and appereantly everything works fine. However there's a little problem. When I click on the menu toolbar the view gets completely blank getting visible only when I interact with it. Seems like the control stops reciving the 'paint window' event when I call MenuSelect function. All the events are managed by the parent window because of the nature of the application (videogame). Does anybody know what this behaviour is due to and how can I avoid it? Thanks for all.

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  • Linq to SQL inheritance and Table per Class - approach needed for multiple roles

    - by Ash Machine
    I am using L2S and an inheritance model for mapping Persons against certain roles. Guy Burstein's excellent blog post explains how to accomplish this: http://blogs.microsoft.co.il/blogs/bursteg/archive/2007/10/01/linq-to-sql-inheritance.aspx However, I have a specific case where a Person has multiple roles. For example 'Jane Doe' is a Contact and a Programmer. In this model, she would need two rows in the People table, one as Contact (PersonType = 1) and one as Programmer (PersonType = 3). If she changes her last name, and that update happens in her role as Contact, I would need to change all instances of 'Jane Doe' to reflect the name change everywhere. What sort of best approach (improved data structure) could be used to change last name within all roles? Finally, I am hoping to avoid overriding each general form update events to include all instances, but that may be the only way. Any suggestions or approaches appreciated.

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  • Hibernate Unit tests - Reset schema

    - by Marco
    Hi, I'm testing the CRUD operations of my DAOs in JUnit tests. When i execute the single test, Hibernate always resets the schema and populates the DB in a known state. But when i execute multiple tests in a row, Hibernate resets the schema once, and then the data is accumulated during the execution of the tests. This is an unexpected behavior, so I'd like to add in the @Before method of the tests a function that explicitly resets the schema to avoid the pesistence of side data created by previous tests during the execution chain. Any tips? Thanks

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  • Unreachable, existing 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

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  • How can I add similar functionality to a number of methods in java?

    - by Roman
    I have a lot of methods for logging, like logSomeAction, logAnotherAction etc. Now I want all these methods make a small pause after printing messages (Thread.sleep). If I do it manually, I would do something like this: //before: public static void logSomeAction () { System.out.println (msg(SOME_ACTION)); } //after: public static void logSomeAction () { System.out.println (msg(SOME_ACTION)); try { Thread.sleep (2000); } catch (InterruptedException ignored) { } } I remember that Java has proxy classes and some other magic-making tools. Is there any way avoid copy-n-pasting N sleep-blocks to N logging methods?

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  • PHP regular expression subpattern behaviour

    - by codecowboy
    I want to match both the src and title attributes of an image tag: pattern: <img [^>]*src=["|\']([^"|\']+["|\'])|title=["|\']([^"|\']+) target: <img src="http://someurl.jpg" class="quiz_caption" title="Caption goes here!"> This pattern gives me one unwanted match, title="content", and the match I actually want which is the value between the quotes after the word 'title', i.e 'content'. So, my matches are: <img src="http://someurl.jpg http://someurl.jpg title="Caption goes here!" Caption goes here! Is there a way to avoid the third of these matches? I'm using PCRE in PHP 5.2.x

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  • Three boolean values saved in one tinyint

    - by Casper
    Hello, probably a simple question but I seem to be suffering from programmer's block. :) I have three boolean values: A, B, and C. I would like to save the state combination as an unsigned tinyint (max 255) into a database and be able to derive the states from the saved integer. Even though there are only a limited number of combinations, I would like to avoid hard-coding each state combination to a specific value (something like if A=true and B=true has the value 1). I tried to assign values to the variables so (A=1, B=2, C=3) and then adding, but I can't differentiate between A and B being true from i.e. only C being true. I am stumped but pretty sure that it is possible. Thanks

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  • Hashing a python function to regenerate output when the function is modified

    - by Seth Johnson
    I have a python function that has a deterministic result. It takes a long time to run and generates a large output: def time_consuming_function(): # lots_of_computing_time to come up with the_result return the_result I modify time_consuming_function from time to time, but I would like to avoid having it run again while it's unchanged. [time_consuming_function only depends on functions that are immutable for the purposes considered here; i.e. it might have functions from Python libraries but not from other pieces of my code that I'd change.] The solution that suggests itself to me is to cache the output and also cache some "hash" of the function. If the hash changes, the function will have been modified, and we have to re-generate the output. Is this possible or ridiculous? Updated: based on the answers, it looks like what I want to do is to "memoize" time_consuming_function, except instead of (or in addition to) arguments passed into an invariant function, I want to account for a function that itself will change.

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  • How to automatically check out a database file in a source controlled web application ?

    - by TheRHCP
    Hello, I am working on an ASP.NET web application, we are a small team (4 students) and we do not have access to a dedicated server to host the database instance. So for this web application we decided just to put the database file in the App_Data folder. The problem is that our project is source controled on TFS, so every time you open the solution and try to launch the web application, we get an expcetion saying that database is read-only. That is logical because the databse file is not automatically checked-out. Is there a workaround to avoid a manual check-out of the database file everytime we open the solution ? Thanks.

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