Search Results

Search found 15423 results on 617 pages for 'uses clause'.

Page 520/617 | < Previous Page | 516 517 518 519 520 521 522 523 524 525 526 527  | Next Page >

• Porting Symbian C++ to Android NDK

  - by Donal Rafferty

  I've been given some Symbian C++ code to port over for use with the Android NDK. The code has lots of Symbian specific code in it and I have very little experience of C++ so its not going very well. The main thing that is slowing me down is trying to figure out the alternatives to use in normal C++ for the Symbian specific code. At the minute the compiler is throwing out all sorts of errors for unrecognised types. From my recent research these are the types that I believe are Symbian specific: TInt, TBool, TDesc8, RSocket, TInetAddress, TBuf, HBufc, RPointerArray Changing TInt and TBool to int and bool respectively works in the compiler but I am unsure what to use for the other types? Can anyone help me out with them? Especially TDesc, TBuf, HBuf. Also Symbian has a two phase contructor using NewL and NewLc But would changing this to a normal C++ constructor be ok? Finally Symbian uses the clean up stack to help eliminate memory leaks I believe, would removing the clean up stack code be acceptable, I presume it should be replaced with try/catch statements?

  Read the article

• Anyone Experiencing Slow Builds With VS2010?

  - by MrKWatkins

  Hi, We've recently upgraded to the final release of VS2010 and are experiencing very slow build times compared to the same code under 2008. I was wondering if anyone else is experiencing the same so I can work out whether it's just our environment or not? A few details: Using VS2010 Ultimate on Windows 7 with fairly beefy machines, talking to TFS 2010. The solution has been upgraded from VS2008 but still builds against .NET 3.5 and ASP.NET MVC 1.0. It doesn't seem to be the compilation itself taking long but something else in the build process. This is because even projects that are up to date and don't need compiling are taking a few seconds or so to process. It's not due to an Visual Studio addin because a couple guys in the team haven't installed any. The first build after loading VS2010 is pretty quick, then they seem to slow down over time. For example on of the projects in my solution just took 00:00:00.08 to process after a restart. (The project was up to date and didn't need compiling) I then immediately hit rebuild and it jumps to 00:00:01.33. We're also experiencing the problem with another solution that uses .NET 4.0 that was building perfectly fine under VS2010 RC. There are no build events or anything like that I can blame, just straightforward assembly builds. The IDE is not very responsive during the slow builds. Anyone else has similar problems? Update: It looks like the resolving assembly references is taking a long time. Looking at the MSBuild diagnostic output or the example above the first build has 30ms for ResolveAssemblyReferences, the second build has 800ms. Subsequent builds seem to be taking longer copying stuff around, e.g. CopyFilesToOutputDirectory jumps from 1ms to 27ms.

  Read the article

• CSS Sprite for images which have vertical as well as horizontal repeats

  - by Rachel

  I have four images, one of which has background repeat property in horizontal direction and three of which have background repeat in vertical direction. I have different CSS classes which currently uses this images as under: .sb_header_dropdown { background: url(images/shopping_dropdown_bg.gif) repeat-y top left; padding: 8px 3px 8px 15px; } .shopping_basket_dropdown .sb_body { background: url(images/shopping_dropdown_body_bg.png) repeat-y top left; margin: 0; padding: 5px 9px 5px 8px; position: relative; z-index: 99999; } .checkout_cart .co_header_left { background: url(images/bg.gif) repeat-x 0 -150px; overflow: hidden; padding-left: 3px; } .sb_dropdown_footer { background: url(images/shopping_dropdown_footer_bg.png) repeat-y top left; clear: both; height: 7px; font-size: 0; } So here am making 4 HTTP Request and I want to implement CSS Sprite for all 4 images such that I can reduce the number of HTTP Request from 4 to 1, also thing to keep in mind is that here we have background repeat for all 4 images, either on x-direction or on y-direction and so how should sprite be created and how it can be used in the CSS to reduce the number of HTTP request. I hope this question is clear.

  Read the article

• simple image animation with the keyboard

  - by conorhiggins

  Hi the app I am currently working on requires a simple animation to be performed, which I am able to do but timing is an issue. The app uses the slightly opaque keyboard and I have set up a black background to make it more visually pleasing . The app is a utility app and as the user clicks on a settings button the app will flip which looks great. However there is a problem at the moment in that while the app is flipping the keyboard also closes which itself looks great also, however the background remains. I was wondering if there was a way of animating the background image to follow the keyboard's animation pattern and speed? If I set up a discrete animation time the chances are there will be some sort of overlap and either the image will show too long or the keyboard will show too long. Any suggestions? Another option is to make the keyboard show constantly if anyone knows how to do that? i would rather animate it though as it is quite a simple app and so I would like to make it as aesthetically pleasing as possible. /Conor

  Read the article

• .NET security mechanism to restrict access between two Types in the same project?

  - by jdk

  Question: Is there a mechanism in the .NET Framework to hide one custom Type from another without using separate projects/assemblies? I'm using C# with ASP.NET in a Website project. Note: I'm not talking about access modifiers to hide members of a Type from another type - I mean to hide the Type itself. Background: I'm working in an ASP.NET Website project and the team has decided not to use separate project assemblies for different software layers. Therefore I'm looking for a way to have, for example, a DataAccess/ folder of which I disallow its classes to access other Types in the same ASP.NET Website project. In other words I want to fake the layers and have some kind of security mechanism around each layer to prevent it from accessing another. Obviously there's not a way to enforce this restriction using language-specific OO keywords so I am looking for something else, for example: maybe a permission framework or code access mechanism, maybe something that uses meta data like Attributes. Even something that restricts one namespace from accessing another. I'm unsure the final form it might take. If this were C++ I'd likely be using friend to make as solution, which doesn't translate to C# internal in this case although they're often compared. I don't really care whether the solution actually hides Types from each other or just makes them inaccessible; however I don't want to lock down one Type from all others, another reason access modifiers are not a solution. A runtime or design time answer will suffice. Looking for something easy to implement otherwise it's not worth the effort ...

  Read the article

• JavaScript Fails to load content correctly on start

  - by Gaz_Edge

  I have inherited an image gallery constructed using javascript. I believe it uses a variation of JQuery, but it seems to have been heavily edited. The gallery loads the first image on page load. Each image has comments below them. There are forward and backward arrows that move between images. The problem I seem to have is that if there is a comment on image one, it is not loaded on page start, the only way to get it to display is to click forward to the next image, then click back to image one. The comment is then shown. All the comments are loaded into a script in the header under var sent_comments = [{COMMENTS}] The comment HTML code on loading is as follows; <div id="comments_container"> <div id="comments"> </div> </div> Once I have clicked to image two and then back to image one, the code is; <div id="comments_container"> <div id="comments"> SOME COMMENT </div> </div> Previous image button is: <a class="prev save_state" href="#"> <img src="/next.png?" alt="Next"> </a> Im new to javascript so not really sure what I will need to do to ensure the comment is loaded for the first image when the page loads. Code here: http://static.albumexposure.net/assets/presentation-9f47b054d96f9ec2459e89619a5fe9b4.js http://static.albumexposure.net/assets/presentations/book-699d82a2beb39df264e54c5d2578e0e4.js

  Read the article

• Finding patterns of failure in a Unit Test

  - by Pekka

  I'm new to Unit Testing, and I'm only getting into the routine of building test suites. I have what is going to be a rather large project that I want to build tests for from the start. I'm trying to figure out general strategies and patterns for building test suites. When you look at a class, many tests come to you obviously due to the nature of the class. Say for a "user account" class with basic CRUD operations, being related to a database table, we will want to test - well, the CRUD. creating an object and seeing whether it exists query its properties change some properties change some properties to incorrect values and delete it again. As for how to break things, there are "fail" tests common to most CRUD classes like: Invalid input data types A number as the ID key that exceeds the range of the chosen data type Input in an incorrect character encoding Input that is too long And so on and so on. For a unit test concerned with file operations, the list of "breaking things" could be Invalid characters in file name File name too long File name uses incorrect protocol or path I'm pretty sure similar patterns - applicable beyond the unit test one is currently working on - can be found for most units that are being tested. Now my question is: Am I correct in seeing such "breaking patterns"? Or am I getting something completely wrong about Unit testing, and if I did it right, this wouldn't be an issue at all? Is Unit Testing as a process of finding as many ways to break the unit as possible the right way to go? If I am correct: Are there existing definitions, lists, cheat sheets for such patterns? Are there any provisions (mainly in PHPUnit, as that's the framework I'm working in) to automate such patterns? Is there any assistance - in the form of check lists, or software - to aid in writing complete tests?

  Read the article

• Shared Git repo syncing to svn causing git svn rebase to pollute repo with a log of no-op merge prob

  - by John K

  This wasn't so bad at the beginning, but now I have hundreds of no-op merge problems (solved by git rebase --skip). I have setup a shared git repo for my group because it is easier to deal with. But the company uses SVN so I have to keep SVN in sync with GIT. Worked like a dream at first, but after weeks of doing this GIT is giving me a lot of the following errors. Applying: * making all config actions work Using index info to reconstruct a base tree... Falling back to patching base and 3-way merge... Auto-merging app/controllers/vulnerabilities_controller.rb CONFLICT (content): Merge conflict in app/controllers/vulnerabilities_controller.rb Auto-merging public/javascripts/network_analysis_vulnerability_config.js CONFLICT (content): Merge conflict in public/javascripts/network_analysis_vulnerability_config.js Failed to merge in the changes. Patch failed at 0046 * making all config actions work My workflow: git co master git pull origin git svn rebase ... deal with no-op merge problems ... git svn dcommit git pull origin git push origin The problem is that what is in SVN is the correct so I use git rebase --skip, but I have to do that hundreds of times before I can dcommit. How do I clear these merge problems permanently?

  Read the article

• In Javascript, what's better than try/catch for exiting an outer scope?

  - by gruseom

  In Javascript, I sometimes want to return a value from a scope that isn't the current function. It might be a block of code within the function, or it might be an enclosing function as in the following example, which uses a local function to recursively search for something. As soon as it finds a solution, the search is done and the whole thing should just return. Unfortunately, I can't think of a simpler way to do this than by hacking try/catch for the purpose: function solve(searchSpace) { var search = function (stuff) { solution = isItSolved(stuff); if (solution) { throw solution; } else { search(narrowThisWay(stuff)); search(narrowThatWay(stuff)); }; }; try { return search(searchSpace); } catch (solution) { return solution; }; }; I realize one could assign the solution to a local variable and then check it before making another recursive call, but my question is specifically about transfer of control. Is there a better way than the above? Perhaps involving label/break?

  Read the article

• Continuously updating chat messages

  - by Daniel

  I'm creating a very simple chat application. It has an ASP.NET web page as front-end and a WCF service as back-end for storing the messages to a database. Everything works great except one thing; when Browser A enters a chat message I want Browser B to see the message as soon as possible (yeah, I know, that's the purpose of a chat). What I've done so far is to setup a trigger within the UpdatePanel, like this: <Triggers> <asp:AsyncPostBackTrigger ControlID="chatTimer" EventName="Tick" /> </Triggers> which uses a timer: <asp:Timer ID="chatTimer" runat="server" OnTick="chatTimer_Tick" Interval="1000" /> Is this the best approach or is there a better, yet simple, way to accomplish updating of messages. One drawback with this solution is that the textbox used to enter chat messages loses focus every time the Tick event runs. Any piece of feedback or advice regarding updating of messages is appreciated. Thank you!

  Read the article

• How often should network traffic/collisions cause SNMP Sets to fail?

  - by A. Levy

  My team has a situation where an SNMP SET will fail once every two weeks or so. Since this set happens automatically, we don't necessarily notice it immediately when it fails, and this can result in an inconsistent configuration and associated wailing and gnashing of teeth. The plan is to fix this by having our software automatically retry the SET when it fails. The problem is, we aren't sure why the failure is happening. My (extremely limited) knowledge of SNMP isn't particularly helpful in diagnosing this problem, so I thought I'd ask StackOverflow for some advice. We think that every so often a spike in network traffic will cause the SET to fail. Since SNMP uses UDP for communication, I would think it would be relatively easy for a command to be drowned out if traffic was high for a short period of time. However, I have no idea how common this is. We have a small network with a single cisco router and there are less than a dozen SNMP controlled devices on that network. In addition to the SNMP traffic, there are some status web pages being loaded from the various devices. In case it makes a difference, I believe we are using the AdventNet SNMP API version 4.0.4 for Java. Does it sound reasonable that there will be some SET commands dropped occasionally, or should we be looking for other causes?

  Read the article

• How to change database connection without compiling, using JBoss Seam?

  - by MLB

  Hi there: I am developing a web site in Eclipse using JBoss Seam 1.2. My site uses a database (named ALregcli) hosted in a MySQL server. That database has only one table named trazasfallos. The server I am using is local (localhost). When I deploy the site in an "X HOST", the MySQL server it is not in the same computer... the server is in an "Y HOST", so, the connection will not be stablished to the database. I was changing the Context.xml, but it didn't work. The only way it worked was changing the host to connect to in the Context.xml and "recompiling" all the project. Then, it generates the new version of the compiled class trazasfallos.class, and this is the file I have to overwrite for connecting to a new database server. The point is that I want to make the change without "recompiling" anything... Maybe there is a way to make only a "text change" and it will work (maybe in a .xml file)... but I don't know how to do it!! The question is: how to change the connection to the database without recompiling anything in the site?? I am sorry about my English, I am from Cuba.

  Read the article

• No class def found error for JUnit Test on android

  - by J Bellamy

  I am having some very bizarre behaviour. I have a large number of test cases for my Android application, and they all work except for one. When I run this one I get a java.lang.NoClassDefFoundError: org.JUnit.test Yes, I have the JUnit 4 library imported into the project, and my other JUnit tests are running without any problems. What is particularly bizarre is that before I hit this problem I had an error in my code- basically, I tried writing a file to a read only folder. When that occurred, the JUnitTest would execute up to the point where it would hit an IO exception for accessing a part of memory it cannot access. I fix this problem, and suddenly the Android emulator doesn't seem to know what org.JUnit.test is. I have examined the run configuration for this test class, and it is the same as my others. It is in the same folder as the other tests as well. It also uses the same import statements. Any idea on what is going on? I am using the Android 10 emulator, and eclipse version 3.7.2. Edit: To clarify, the error I get appears on Logcat and not in my Eclipse project.

  Read the article

• Get parameter values from method at run time

  - by Landin Martens

  I have the current method example: public void MethodName(string param1,int param2) { object[] obj = new object[] { (object) param1, (object) param2 }; //Code to that uses this array to invoke dynamic methods } Is there a dynamic way (I am guessing using reflection) that will get the current executing method parameter values and place them in a object array? I have read that you can get parameter information using MethodBase and MethodInfo but those only have information about the parameter and not the value it self which is what I need. So for example if I pass "test" and 1 as method parameters without coding for the specific parameters can I get a object array with two indexes { "test", 1 }? I would really like to not have to use a third party API, but if it has source code for that API then I will accept that as an answer as long as its not a huge API and there is no simple way to do it without this API. I am sure there must be a way, maybe using the stack, who knows. You guys are the experts and that is why I come here. Thank you in advance, I can't wait to see how this is done. EDIT It may not be clear so here some extra information. This code example is just that, an example to show what I want. It would be to bloated and big to show the actual code where it is needed but the question is how to get the array without manually creating one. I need to some how get the values and place them in a array without coding the specific parameters.

  Read the article

• How to load/save C++ class instance (using STL containers) to disk

  - by supert

  I have a C++ class representing a hierarchically organised data tree which is very large (~Gb, basically as large as I can get away with in memory). It uses an STL list to store information at each node plus iterators to other nodes. Each node has only one parent, but 0-10 children. Abstracted, it looks something like: struct node { public: node_list_iterator parent; // iterator to a single parent node double node_data_array[X]; map<int,node_list_iterator> children; // iterators to child nodes }; class strategy { private: list<node> tree; // hierarchically linked list of nodes struct some_other_data; public: void build(); // build the tree void save(); // save the tree from disk void load(); // load the tree from disk void use(); // use the tree }; I would like to implement the load() and save() to disk, and it should be fairly fast, however the obvious problems are: I don't know the size in advance; The data contains iterators, which are volatile; My ignorance of C++ is prodigious. Could anyone suggest a pure C++ solution please?

  Read the article

• Triangulation in 3D Space

  - by w3b_wizzard

  Disclaimer: This is for class, however I'm fresh out of ideas and a nudge in the right direction would be much appreciated. Also, this needs to be implemented in raw C, so no fancy libraries can be used. I have to write a search and rescue simulator for submarines, it has to find a probe that is randomly placed in 3D space in a grid from of the MAX_XYZ (100000). The only tools I'm given are a "ping" which will give the magnitude of the distance between a certain sub and the probe. The goal is to optimize the costs of this entire operation so a brute force attempt, like looking at every single coordinate, won't work. Hence I was thinking triangulation. Now, it makes loads of sense to me, place three subs, each one of them uses their ping to get the distance between them and the probe. Since each sub have a known distance relative to one another, it's easy to build the base of a tetrahedron with them, and the results of the ping will point to a certain coordinate, the problem I'm having is how to figure out the elevation, or the height, of the tetrahedron. So what I have as data is the following: Distances between subs (In vector format) Angles between each subs (very easy to compute) Distance between each sub and the probe (3 segments from the base to the peak) Angles inside each of the outer 3 surfaces of the tetrahedron. I tried finding some sort of relationship with the vertices of the tetrahedron and the relative angles in each of them, however all I found had to deal with tetrahedrons built with equilateral triangles, which isn't much help. I have the impression this can be easily solved with trig but either I'm not seeing it or I need more coffee. Any suggestions would be appreciated!

  Read the article

• [Concept] How does unlink() find the file to delete?

  - by Prasad

  My app has a 'Photo' field to store URL. It uses sfWidgetFormInputFileEditable for the widget schema. To delete the old image when a new image is uploaded, I use unlink before setting the value in the over-ridden setter and it works!!! if (file_exists($this->_get('photo'))) unlink($this->_get('photo')); Photos are stored in uploads/photos and when saving 'Photo' only the file name xxx-yyy.zzz is saved (and not the full path). However, I wish to know how symfony/php knows the full path of the file to be deleted? Part 2: I am using sfThumbnailPlugin to generate thumbnails. So the actual code looks like this: public function setPhoto($value) { if(!empty($value)) { Contact::generateThumbnail($value); // delete current Photo & create thumbnail $this->_set('photo',$value); // setting new value after deleting old one } } public function generateThumbnail($value) { $uploadDir = sfConfig::get('app_photo_upload'); // path to upload folder if (file_exists($this->_get('photo'))) { unlink($this->_get('photo')); // delete full-size image // path to thumbnail $thumbpath = $uploadDir.'/thumbnails/'.$this->get('photo'); // read a blog, tried setting dir manually, doesn't work :( //chdir('/thumbnails/'); // tried closing the file too, doesn't work! :( //fclose($thumbpath) or die("can't close file"); //unlink($this->_get('photo')); // doesn't work; no error :( unlink($thumbpath); // doesn't work, no error :( } $thumbnail = new sfThumbnail(150, 150); $thumbnail->loadFile($uploadDir.'/'.$value); $thumbnail->save($uploadDir.'/thumbnails/'.$value, 'image/png'); } Why can't the thumbnail be deleted using unlink()? is the sequence of ops incorrect? Is it because the old thumbnail is displayed in the sfWidgetFormInputFileEditable widget? I've spent hours trying to figure this out, but unable to nail down the real cause. Thanks in advance.

  Read the article

• Web page for IPhone - Large fonts instead of scrolling?

  - by chris_l

  I'm planning the layout of my web page, which should also be usable on the IPhone. I don't really have much experience with the IPhone yet - I just installed the IPhone Simulator on my Mac. The page's contents are flexible, so I think it would be better to use this flexibility to avoid that the user has to scroll around the entire page. Especially I have A header and a sidebar that will be used all the time to perform several actions. A main content area with a number of elements (e.g. images). The UI would stay usable pretty well, if the number of elements shown at one time is reduced for a small screen (e.g. by JavaScript). It would also be okay to make the main content area scrollable (as opposed to the entire page). The problem: If I simply display the page on the IPhone, it uses an extremely small font size, so that users must zoom in first, and then scroll around - so that they can't see the header and sidebar all the time. What's the best way to deal with this situation? Just leave it this way (very small fonts), because users expect that behaviour on the IPhone? Increase the font size (by specifying it in em or px or with xx-large, or what would be the best way?), if I detect - somehow - that it's being displayed on the IPhone. Or is there some way to restrict the viewport size to the screen size, and make it zoom in automatically? I think that would be the easiest solution in my case. Or ...?

  Read the article

• Efficiently get the size of a parameter pack up to a certain index

  - by NmdMystery

  I want to be able to determine the number of bytes that are in a subset of a parameter pack from 0 to a given index. Right now I'm using a non-constexpr way of doing this. Below is my code: template <size_t index, typename... args> struct pack_size_index; template <size_t index, typename type_t, typename... args> struct pack_size_index <index, type_t, args...> { static const size_t index_v = index; static const size_t value(void) { if (index_v > 0) { return sizeof(type_t) + pack_size_index<index - 1, args...>::value(); } return 0; } }; template <size_t index> struct pack_size_index <index> { static const size_t index_v = index; static const size_t value(void) { return 0; } }; Usage: //output: 5 (equal to 1 + 4) std::cout << pack_size_index<2, bool, float, int, double>::value() << std::endl; //output: 20 (equal to 8 + 8 + 4) std::cout << pack_size_index<3, double, double, float, int>::value() << std::endl; This gets the job done, but this uses runtime comparison and the resulting executable increases in size rapidly whenever this is used. What's a less expensive way of doing this?

  Read the article

• c++ overloading delete, retrieve size

  - by user300713

  Hi, I am currently writing a small custom memory Allocator in c++, and want to use it together with operator overloading of new/delete. Anyways, my memory Allocator basicall checks if the requested memory is over a certain threshold, and if so uses malloc to allocate the requested memory chunk. Otherwise the memory will be provided by some fixedPool allocators. that generally works, but for my deallocation function looks like this: void MemoryManager::deallocate(void * _ptr, size_t _size){ if(_size heapThreshold) deallocHeap(_ptr); else deallocFixedPool(_ptr, _size); } so I need to provide the size of the chunk pointed to, to deallocate from the right place. No the problem is that the delete keyword does not provide any hint on the size of the deleted chunk, so I would need something like this: void operator delete(void * _ptr, size_t _size){ MemoryManager::deallocate(_ptr, _size); } But as far as I can see, there is no way to determine the size inside the delete operator.- If I want to keep things the way it is right now, would I have to save the size of the memory chunks myself? Any ideas on how to solve this are welcome! Thanks!

  Read the article

• including pre-built java classes into an android project

  - by moonlightcheese

  i'm trying to include a maven java project into my android project. the maven project is the greader-unofficial project which allows developers access to google reader accounts, and handles all of the http transactions and URI/URL building, making grabbing feeds and items from google reader transparent to the developer. the project is available here: http://code.google.com/p/greader-unofficial/ the code is originally written for the standard jdk and uses classes from java.net that are not a part of the standard Android SDK. i actually tried to manually resolve all dependencies and ran into a problem when i got as far as including com.sun.syndication pieces required by the class be.lechtitseb.google.reader.api.util.AtomUtil.java... some of the classes in java.net that are in the standard jdk (i'm using 1.6) are not in the Android SDK. in addition, resolving all of these dependencies manually is just ridiculous when i'm compiling a maven project that should be pretty simple. however, i can use maven to compile the sources with no issue. how can i include this maven project, which is dependent on the complete jdk, into my android project in such a way that it will compile so that i can access the GoogleReader class from my android project? and for the record, i don't have the expertise to rewrite this entire api to work with the standard Android SDK.

  Read the article

• Is it possible to create a null function that will not produce warnings?

  - by bbazso

  I have a logger in a c++ application that uses defines as follows: #define FINEST(...) Logger::Log(FINEST, _FILE, __LINE, __func, __VA_ARGS_) However what I would like to do is to be able to switch off these logs since they have a serious performance impact on my system. And, it's not sufficient to simply have my Logger not write to the system log. I really need to get rid of the code produced by the logs. In order to do this, I changed the define to: #define FINEST(...) Which works, but this produces a whole bunch of warning in my code since variables are unused now. So what I would like to have is a sort of NULL FUNCTION that would not actually exist, but would not produce warnings for the unused variables. So, said another way, I would like it to compile with no warnings (i.e. the compiler thinks that the variables are used for a function) but the function does not actually exist in the application (i.e. produces no performance hit). Is this possible? Thanks!

  Read the article

• How do I make a lock that allows only ONE thread to read from the resource ?

  - by mare

  I have a file that holds an integer ID value. Currently reading the file is protected with ReaderWriterLockSlim as such: public int GetId() { _fileLock.EnterUpgradeableReadLock(); int id = 0; try { if(!File.Exists(_filePath)) CreateIdentityFile(); FileStream readStream = new FileStream(_filePath, FileMode.Open, FileAccess.Read); StreamReader sr = new StreamReader(readStream); string line = sr.ReadLine(); sr.Close(); readStream.Close(); id = int.Parse(line); return int.Parse(line); } finally { SaveNextId(id); // increment the id _fileLock.ExitUpgradeableReadLock(); } } The problem is that subsequent actions after GetId() might fail. As you can see the GetId() method increments the ID every single time, disregarding what happens after it has issued an ID. The issued ID might be left hanging (as said, exceptions might occur). As the ID is incremented, some IDs might be left unused. So I was thinking of moving the SaveNextId(id) out, remove it (the SaveNextId() actually uses the lock too, except that it's EnterWriteLock). And call it manually from outside after all the required methods have executed. That brings out another problem - multiple threads might enter the GetId() method before the SaveNextId() gets executed and they might all receive the same ID. I don't want any solutions where I have to alter the IDs after the operation, correcting them in any way because that's not nice and might lead to more problems. I need a solution where I can somehow callback into the FileIdentityManager (that's the class that handles these IDs) and let the manager know that it can perform the saving of the next ID and then release the read lock on the file containing the ID. Essentialy I want to replicate the relational databases autoincrement behaviour - if anything goes wrong during row insertion, the ID is not used, it is still available for use but it also never happens that the same ID is issued. Hopefully the question is understandable enough for you to provide some solutions..

  Read the article

• content_tag_for a collection in Rails?

  - by Nick

  I have a Post model. Posts have many Comments. I want to generate a <ul> element for post.comments using content_tag_for. Ideally, it'd produce <ul id="comments_post_7" class="comments"> ... </ul> where 7 is the ID of the Post. The closest I can get uses <% content-tag-for :ul post, :comments do %> which produces <ul id="comments_post_7" class="post"> ... </ul> which is pretty close, except for the class="post". Using :class => :comments in the content_tag_for yields class="post comments", but I just want class="comments". It seems logical that I'd be able to use something like <% content_tag_for :ul post.comments do %> but, sadly, that yields <ul id="array_2181653100" class="array"> ... </ul> I've searched far and wide. I feel like I'm missing some elegant way to do this. Am I? Because, seriously, <ul id="comments_post_<%= post.id %>" class="comments"> is painful.

  Read the article

• Checked and Unchecked operators don't seem to be working when...

  - by flockofcode

  1) Is UNCHECKED operator in effect only when expression inside UNCHECKED context uses an explicit cast ( such as byte b1=unchecked((byte)2000); ) and when conversion to particular type can happen implicitly? I’m assuming this since the following expression throws a compile time error: byte b1=unchecked(2000); //compile time error 2) a) Do CHECKED and UNCHECKED operators work only when resulting value of an expression or conversion is of an integer type? I’m assuming this since in the first example ( where double type is being converted to integer type ) CHECKED operator works as expected: double m = double.MaxValue; b=checked((byte)m); // reports an exception , while in second example ( where double type is being converted to a float type ) CHECKED operator doesn’t seem to be working. since it doesn't throw an exception: double m = double.MaxValue; float f = checked((float)m); // no exception thrown b) Why don’t the two operators also work with expressions where type of a resulting value is of floating-point type? 2) Next quote is from Microsoft’s site: The unchecked keyword is used to control the overflow-checking context for integral-type arithmetic operations and conversions I’m not sure I understand what exactly have expressions and conversions such as unchecked((byte)(100+200)); in common with integrals? Thank you

  Read the article

< Previous Page | 516 517 518 519 520 521 522 523 524 525 526 527  | Next Page >