Search Results

Search found 89551 results on 3583 pages for 'code ed student'.

Page 47/3583 | < Previous Page | 43 44 45 46 47 48 49 50 51 52 53 54  | Next Page >

  • What books help one to learn to read code?

    - by Daniel
    Lion's Commentary on Unix Sixth Edition with Source Code is a wonderful book to learn how to read code. Reading code is important -- how does one learn how to write excellent code without having read excellent code? But, sadly, while great writers, of fiction and non-fiction, all spend a great deal of time reading stuff, we, programmers, seem to avoid it like the plague. Worse still, programming books usually go the same way. They might show a pattern or a style, but they often avoid showing good, complex code, and helping one go through it. There are exceptions, of course. I hope. So, with that in mind, what books are to be found which help one learn how to read code?

    Read the article

  • Using the StopWatch class to calculate the execution time of a block of code

    - by vik20000in
      Many of the times while doing the performance tuning of some, class, webpage, component, control etc. we first measure the current time taken in the execution of that code. This helps in understanding the location in code which is actually causing the performance issue and also help in measuring the amount of improvement by making the changes. This measurement is very important as it helps us understand the problem in code, Helps us to write better code next time (as we have already learnt what kind of improvement can be made with different code) . Normally developers create 2 objects of the DateTime class. The exact time is collected before and after the code where the performance needs to be measured.  Next the difference between the two objects is used to know about the time spent in the code that is measured. Below is an example of the sample code.             DateTime dt1, dt2;             dt1 = DateTime.Now;             for (int i = 0; i < 1000000; i++)             {                 string str = "string";             }             dt2 = DateTime.Now;             TimeSpan ts = dt2.Subtract(dt1);             Console.WriteLine("Time Spent : " + ts.TotalMilliseconds.ToString());   The above code works great. But the dot net framework also provides for another way to capture the time spent on the code without doing much effort (creating 2 datetime object, timespan object etc..). We can use the inbuilt StopWatch class to get the exact time spent. Below is an example of the same work with the help of the StopWatch class.             Stopwatch sw = Stopwatch.StartNew();             for (int i = 0; i < 1000000; i++)             {                 string str = "string";             }             sw.Stop();             Console.WriteLine("Time Spent : " +sw.Elapsed.TotalMilliseconds.ToString());   [Note the StopWatch class resides in the System.Diagnostics namespace] If you use the StopWatch class the time taken for measuring the performance is much better, with very little effort. Vikram

    Read the article

  • Managing common code on Windows 7 (.NET) and Windows 8 (WinRT)

    - by ryanabr
    Recent announcements regarding Windows Phone 8 and the fact that it will have the WinRT behind it might make some of this less painful but I  discovered the "XmlDocument" object is in a new location in WinRT and is almost the same as it's brother in .NET System.Xml.XmlDocument (.NET) Windows.Data.Xml.Dom.XmlDocument (WinRT) The problem I am trying to solve is how to work with both types in the code that performs the same task on both Windows Phone 7 and Windows 8 platforms. The first thing I did was define my own XmlNode and XmlNodeList classes that wrap the actual Microsoft objects so that by using the "#if" compiler directive either work with the WinRT version of the type, or the .NET version from the calling code easily. public class XmlNode     { #if WIN8         public Windows.Data.Xml.Dom.IXmlNode Node { get; set; }         public XmlNode(Windows.Data.Xml.Dom.IXmlNode xmlNode)         {             Node = xmlNode;         } #endif #if !WIN8 public System.Xml.XmlNode Node { get; set ; } public XmlNode(System.Xml.XmlNode xmlNode)         {             Node = xmlNode;         } #endif     } public class XmlNodeList     { #if WIN8         public Windows.Data.Xml.Dom.XmlNodeList List { get; set; }         public int Count {get {return (int)List.Count;}}         public XmlNodeList(Windows.Data.Xml.Dom.XmlNodeList list)         {             List = list;         } #endif #if !WIN8 public System.Xml.XmlNodeList List { get; set ; } public int Count { get { return List.Count;}} public XmlNodeList(System.Xml.XmlNodeList list)         {             List = list;        } #endif     } From there I can then use my XmlNode and XmlNodeList in the calling code with out having to clutter the code with all of the additional #if switches. The challenge after this was the code that worked directly with the XMLDocument object needed to be seperate on both platforms since the method for populating the XmlDocument object is completly different on both platforms. To solve this issue. I made partial classes, one partial class for .NET and one for WinRT. Both projects have Links to the Partial Class that contains the code that is the same for the majority of the class, and the partial class contains the code that is unique to the version of the XmlDocument. The files with the little arrow in the lower left corner denotes 'linked files' and are shared in multiple projects but only exist in one location in source control. You can see that the _Win7 partial class is included directly in the project since it include code that is only for the .NET platform, where as it's cousin the _Win8 (not pictured above) has all of the code specific to the _Win8 platform. In the _Win7 partial class is this code: public partial class WUndergroundViewModel     { public static WUndergroundData GetWeatherData( double lat, double lng)         { WUndergroundData data = new WUndergroundData();             System.Net. WebClient c = new System.Net. WebClient(); string req = "http://api.wunderground.com/api/xxx/yesterday/conditions/forecast/q/[LAT],[LNG].xml" ;             req = req.Replace( "[LAT]" , lat.ToString());             req = req.Replace( "[LNG]" , lng.ToString()); XmlDocument doc = new XmlDocument();             doc.Load(c.OpenRead(req)); foreach (XmlNode item in doc.SelectNodes("/response/features/feature" ))             { switch (item.Node.InnerText)                 { case "yesterday" :                         ParseForecast( new FishingControls.XmlNodeList (doc.SelectNodes( "/response/forecast/txt_forecast/forecastdays/forecastday" )), new FishingControls.XmlNodeList (doc.SelectNodes( "/response/forecast/simpleforecast/forecastdays/forecastday" )), data); break ; case "conditions" :                         ParseCurrent( new FishingControls.XmlNode (doc.SelectSingleNode("/response/current_observation" )), data); break ; case "forecast" :                         ParseYesterday( new FishingControls.XmlNodeList (doc.SelectNodes( "/response/history/observations/observation" )),data); break ;                 }             } return data;         }     } in _win8 partial class is this code: public partial class WUndergroundViewModel     { public async static Task< WUndergroundData > GetWeatherData(double lat, double lng)         { WUndergroundData data = new WUndergroundData (); HttpClient c = new HttpClient (); string req = "http://api.wunderground.com/api/xxxx/yesterday/conditions/forecast/q/[LAT],[LNG].xml" ;             req = req.Replace( "[LAT]" , lat.ToString());             req = req.Replace( "[LNG]" , lng.ToString()); HttpResponseMessage msg = await c.GetAsync(req); string stream = await msg.Content.ReadAsStringAsync(); XmlDocument doc = new XmlDocument ();             doc.LoadXml(stream, null); foreach ( IXmlNode item in doc.SelectNodes("/response/features/feature" ))             { switch (item.InnerText)                 { case "yesterday" :                         ParseForecast( new FishingControls.XmlNodeList (doc.SelectNodes( "/response/forecast/txt_forecast/forecastdays/forecastday" )), new FishingControls.XmlNodeList (doc.SelectNodes( "/response/forecast/simpleforecast/forecastdays/forecastday" )), data); break; case "conditions" :                         ParseCurrent( new FishingControls.XmlNode (doc.SelectSingleNode("/response/current_observation" )), data); break; case "forecast" :                         ParseYesterday( new FishingControls.XmlNodeList (doc.SelectNodes( "/response/history/observations/observation")), data); break;                 }             } return data;         }     } Summary: This method allows me to have common 'business' code for both platforms that is pretty clean, and I manage the technology differences separately. Thank you tostringtheory for your suggestion, I was considering that approach.

    Read the article

  • C# 5 Async, Part 3: Preparing Existing code For Await

    - by Reed
    While the Visual Studio Async CTP provides a fantastic model for asynchronous programming, it requires code to be implemented in terms of Task and Task<T>.  The CTP adds support for Task-based asynchrony to the .NET Framework methods, and promises to have these implemented directly in the framework in the future.  However, existing code outside the framework will need to be converted to using the Task class prior to being usable via the CTP. Wrapping existing asynchronous code into a Task or Task<T> is, thankfully, fairly straightforward.  There are two main approaches to this. Code written using the Asynchronous Programming Model (APM) is very easy to convert to using Task<T>.  The TaskFactory class provides the tools to directly convert APM code into a method returning a Task<T>.  This is done via the FromAsync method.  This method takes the BeginOperation and EndOperation methods, as well as any parameters and state objects as arguments, and returns a Task<T> directly. For example, we could easily convert the WebRequest BeginGetResponse and EndGetResponse methods into a method which returns a Task<WebResponse> via: Task<WebResponse> task = Task.Factory .FromAsync<WebResponse>( request.BeginGetResponse, request.EndGetResponse, null); .csharpcode, .csharpcode pre { font-size: small; color: black; font-family: consolas, "Courier New", courier, monospace; background-color: #ffffff; /*white-space: pre;*/ } .csharpcode pre { margin: 0em; } .csharpcode .rem { color: #008000; } .csharpcode .kwrd { color: #0000ff; } .csharpcode .str { color: #006080; } .csharpcode .op { color: #0000c0; } .csharpcode .preproc { color: #cc6633; } .csharpcode .asp { background-color: #ffff00; } .csharpcode .html { color: #800000; } .csharpcode .attr { color: #ff0000; } .csharpcode .alt { background-color: #f4f4f4; width: 100%; margin: 0em; } .csharpcode .lnum { color: #606060; } Event-based Asynchronous Pattern (EAP) code can also be wrapped into a Task<T>, though this requires a bit more effort than the one line of code above.  This is handled via the TaskCompletionSource<T> class.  MSDN provides a detailed example of using this to wrap an EAP operation into a method returning Task<T>.  It demonstrates handling cancellation and exception handling as well as the basic operation of the asynchronous method itself. The basic form of this operation is typically: Task<YourResult> GetResultAsync() { var tcs = new TaskCompletionSource<YourResult>(); // Handle the event, and setup the task results... this.GetResultCompleted += (o,e) => { if (e.Error != null) tcs.TrySetException(e.Error); else if (e.Cancelled) tcs.TrySetCanceled(); else tcs.TrySetResult(e.Result); }; // Call the asynchronous method this.GetResult(); // Return the task from the TaskCompletionSource return tcs.Task; } We can easily use these methods to wrap our own code into a method that returns a Task<T>.  Existing libraries which cannot be edited can be extended via Extension methods.  The CTP uses this technique to add appropriate methods throughout the framework. The suggested naming for these methods is to define these methods as “Task<YourResult> YourClass.YourOperationAsync(…)”.  However, this naming often conflicts with the default naming of the EAP.  If this is the case, the CTP has standardized on using “Task<YourResult> YourClass.YourOperationTaskAsync(…)”. Once we’ve wrapped all of our existing code into operations that return Task<T>, we can begin investigating how the Async CTP can be used with our own code.

    Read the article

  • How to use wget to grab copy of Google Code site documents?

    - by Alex Reynolds
    I have a Google Code project which has a lot of wiki'ed documentation. I would like to create a copy of this documentation for offline browsing. I would like to use wget or a similar utility. I have tried the following: $ wget --no-parent \ --recursive \ --page-requisites \ --html-extension \ --base="http://code.google.com/p/myProject/" \ "http://code.google.com/p/myProject/" The problem is that links from within the mirrored copy have links like: file:///p/myProject/documentName This renaming of links in this way causes 404 (not found) errors, since the links point to nowhere valid on the filesystem. What options should I use instead with wget, so that I can make a local copy of the site's documentation and other pages?

    Read the article

  • Entity Framework Code-First to Provide Replacement for ASP.NET Profile Provider

    - by Ken Cox [MVP]
    A while back, I coordinated a project to add support for the SQL Table Profile Provider in ASP.NET 4 Web Applications.  We urged Microsoft to improve ASP.NET’s built-in Profile support so our workaround wouldn’t be necessary. Instead, Microsoft plans to provide a replacement for ASP.NET Profile in a forthcoming release. In response to my feature suggestion on Connect, Microsoft says we should look for something even better using Entity Framework: “When code-first is officially released the final piece of a full replacement of the ASP.NET Profile will have arrived. Once code-first for EF4 is released, developers will have a really easy and very approachable way to create any arbitrary class, and automatically have the .NET Framework create a table to provide storage for that class. Furthermore developer will also have full LINQ-query capabilities against code-first classes. “ The downside is that there won’t be a way to retrofit this Profile replacement to pre- ASP.NET 4 Web applications. At least there’ll still be the MVP workaround code. It looks like it’s time for me to dig into a CTP of EF Code-First to see what’s available.   Scott Guthrie has been blogging about Code-First Development with Entity Framework 4. It’s not clear when the EF Code-First is coming, but my guess is that it’ll be part of the VS 2010/.NET 4 service pack.

    Read the article

  • Deprecated Methods in Code Base

    - by Jamie Taylor
    A lot of the code I've been working on recently, both professionally (read: at work) and in other spheres (read: at home, for friends/family/etc, or NOT FOR WORK), has been worked on, redesigned and re-implemented several times - where possible/required. This has been in an effort to make things smaller, faster more efficient, better and closer to spec (when requirements have changed). A down side to this is that I now have several code bases that have deprecated method blocks (and in some places small objects). I'm looking at making this code maintainable and easy to roll back on changes. I'm already using version control software in both instances, but I'm left wondering if there are any specific techniques that have been used by others for keeping the superseded methods without increasing the size of compiled outputs? At the minute, I'm simply wrapping the old code in C style multi line comments. Here's an example of what I mean (C style, psuedo-code): void main () { //Do some work //Foo(); //Deprecated method call Bar(); //New method } /***** Deprecated code ***** /// Summary of Method void Foo() { //Do some work } ***** Deprecated Code *****/ /// Summary of method void Bar() { //Do some work } I've added a C style example, simply because I'm more confident with the C style languages. I'm trying to put this question across as language agnostic (hence the tag), and would prefer language agnostic answers, if possible - since I see this question as more of a techniques and design question. I'd like to keep the old methods and blocks for a bunch of reasons, chief amongst them being the ability to quickly restore an older working method in the case of some tests failing, or some unforeseen circumstance. Is there a better way to do this (that multi line comments)? Are there any tools that will allow me to store these old methods in separate files? Is that even a good idea?

    Read the article

  • C# 5.0 Async/Await Demo Code

    - by Paulo Morgado
    I’ve published the sample code I use to demonstrate the use of async/await in C# 5.0. You can find it here. Projects PauloMorgado.AyncDemo.WebServer This project is a simple web server implemented as a console application using Microsoft ASP.NET Web API self hosting and serves an image (with a delay) that is accessed by the other projects. This project has a dependency on Json.NET due to the fact the the Microsoft ASP.NET Web API hosting has a dependency on Json.NET. The application must be run on a command prompt with administrative privileges or a urlacl must be added to allow the use of the following command: netsh http add urlacl url=http://+:9090/ user=machine\username To remove the urlacl, just use the following command: netsh http delete urlacl url=http://+:9090/ PauloMorgado.AsyncDemo.WindowsForms This Windows Forms project contains three regions that must be uncommented one at a time: Sync with WebClient This code retrieves the image through a synchronous call using the WebClient class. Async with WebClient This code retrieves the image through an asynchronous call using the WebClient class. Async with HttpClient with cancelation This code retrieves the image through an asynchronous call with cancelation using the HttpClient class. PauloMorgado.AsyncDemo.Wpf This WPF project contains three regions that must be uncommented one at a time: Sync with WebClient This code retrieves the image through a synchronous call using the WebClient class. Async with WebClient This code retrieves the image through an asynchronous call using the WebClient class. Async with HttpClient with cancelation This code retrieves the image through an asynchronous call with cancelation using the HttpClient class.

    Read the article

  • Is there an alternative to Google Code Search?

    - by blunders
    Per the Official Google Blog: Code Search, which was designed to help people search for open source code all over the web, will be shut down along with the Code Search API on January 15, 2012. Google Code Search is now gone, and since that makes it much harder to understand the features it presented, here's my attempt to render them via information I gathered from a cache of the page for the Search Options: The "In Search Box" just notes the syntax to type the command directly in the main search box instead of using the advance search interface. Package (In Search Box: "package:linux-2.6") Language (In Search Box: "lang:c++") (OPTIONS: any language, actionscript, ada, applescript, asp, assembly, autoconf, automake, awk, basic, bat, c, c#, c++, caja, cobol, coldfusion, configure, css, d, eiffel, erlang, fortran, go, haskell, inform, java, java, javascript, jsp, lex, limbo, lisp, lolcode, lua, m4, makefile, maple, mathematica, matlab, messagecatalog, modula2, modula3, objectivec, ocaml, pascal, perl, php, pod, prolog, proto, python, python, r, rebol, ruby, sas, scheme, scilab, sgml, shell, smalltalk, sml, sql, svg, tcl, tex, texinfo, troff, verilog, vhdl, vim, xslt, xul, yacc) File (In Search Box: "file:^.*.java$") Class (In Search Box: "class:HashMap") Function (In Search Box: "function:toString") License (In Search Box: "license:mozilla") (OPTIONS: null/any-license, aladdin/Aladdin-Public-License, artistic/Artistic-License, apache/Apache-License, apple/Apple-Public-Source-License, bsd/BSD-License, cpl/Common-Public-License, epl/Eclipse-Public-License, agpl/GNU-Affero-General-Public-License, gpl/GNU-General-Public-License, lgpl/GNU-Lesser-General-Public-License, disclaimer/Historical-Permission-Notice-and-Disclaimer, ibm/IBM-Public-License, lucent/Lucent-Public-License, mit/MIT-License, mozilla/Mozilla-Public-License, nasa/NASA-Open-Source-Agreement, python/Python-Software-Foundation-License, qpl/Q-Public-License, sleepycat/Sleepycat-License, zope/Zope-Public-License) Case Sensitive (In Search Box: "case:no") (OPTIONS: yes, no) Also of use in understanding the search tool would be the still live FAQs page for Google Code Search. Is there any code search engine that would fully replace Google Code Search's features?

    Read the article

  • Is there a measure of code rot?

    - by DarenW
    I'm dealing, again, with a messy C++ application, tons of classes with confusing names, objects have pointers into each other and all over, longwinded Boost and STL data types, etc. (Pause and consider your favorite terror of messy legacy code. We probably have it.) The phrase "code rot" oft comes to mind when I work on this project. Is there a quantitative way to measure code rot? I wouldn't expect anything highly meaningful or scientific, since no other measure of code productivity or quality is so fine. I'm not looking for a mere opposite of measures of code quality, but specifically a measure of how many bad things happened after a series of maintenance software "engineers" have had turns hacking at the code. A general measure applying to any language, or many languages, would be great. If there's no such thing, at least for C++, which is a better than average language for creating messes. Maybe something involving a measure of topology of how objects connect during runtime, a count of chunks of commented out code, how mane files a typical variable's usage is scattered over, I don't know... but surely now, a decade into the 21st Century, someone has attempted to define some sort of rot measure. It would be especially interesting to automate a series of svn checkouts, measure the "rottenosity" of each, and plot the decay over time.

    Read the article

  • As a solo programmer, of what use can Gerrit be?

    - by s.d
    Disclaimer: I'm aware of the questions How do I review my own code? and What advantages do continuous integration tools offer on a solo project?. I do feel that this question aims at a different set of answers though, as it is about a specific software, and not about general musings about the use of this or that practice or tech stack. I'm a solo programmer for an Eclipse RCP-based project. To be able to control myself and the quality of my software, I'm in the process of setting up a CSI stack. In this, I follow the Eclipse Common Build Infrastructure guidelines, with the exception that I will use Jenkins rather than Hudson. Sticking to these guidelines will hopefully help me in getting used to the Eclipse way of doing things, and I hope to be able to contribute some code to Eclipse in the future. However, CBI includes Gerrit, a code review software. While I think it's really helpful for teams, and I will employ it as soon as the team grows to at least two developers, I'm wondering how I could use it while I'm still solo. Question: Is there a use case for Gerrit that takes into account solo developers? Notes: I can imagine reviewing code myself after a certain amount of time to gain a little distance to it. This does complicate the workflow though, as code will only be built once it's been passed through code review. This might prove to be a "trap" as I might be tempted to quickly push bad code through Gerrit just to get it built. I'm very interested in hearing how other solo devs have made use of Gerrit.

    Read the article

  • Smarty: Configurable Comments and Code Templates

    - by Martin Fousek
    Hello, today we would like to show you few improvements we have prepared in PHP Smarty Framework for NetBeans 7.3. So let's talk about adjustable toggle comment action and code templates. Configurable Comments As some of you requested we implemented toggle comment action with adjustable behavior. In NetBeans 7.3 you can choose in Options between commenting as a "Smarty comments everywhere" or "Language sensitive comments" in Smarty Templates. Toggle comment language sensitive: Toggle comment as Smarty comment everywhere: Code Templates In NetBeans 7.3 we will provide by default many code templates inside Smarty templates or directly inside Smarty tags. Available should be code templates for all built-in or custom functions and modifiers of Smarty 3.x. Besides that you should be able to define additional custom templates easily in Options -> Editor -> Code Templates for "Smarty Templates" or directly for "Smarty Markup" (which means code templates inside Smarty tag). You can also take advantage of selection's template which are able to wrap your code with chosen Smarty tag. That's all for today. As always, please test it and report all the issues or enhancements you find in NetBeans BugZilla (component php, subcomponent Smarty).

    Read the article

  • Where to put code documentation?

    - by Patrick
    I am currently using two systems to write code documentation (am using C++): Documentation about methods and class members are added next to the code, using the Doxygen format. On a server Doxygen is run on the sources so the output can be seen in a web browser Overview pages (describing a set of classes, the structure of the application, example code, ...) is added to a Wiki I personally think that this approach is easy because the documentation about members and classes is really close to the code, while the overview pages are really easy to edit in the Wiki (and it's also easy to add images, tables, ...). A web browser allows you to see both documentations. My co-worker now suggests to put everything in Doxygen, because we can then create one big help file with everything in it (using either Microsoft's HTML WorkShop or Qt Assistant). My concern is that editing Doxygen-style documentation is much harder (compared to Wiki), especially when you want to add tables, images, ... (or is there a 'preview' tool for Doxygen that doesn't require you to generate the code before you can see the result?) What do big open-source (or closed source) projects use to write their code documentation? Do they also split this up between Doxygen-style and a Wiki? Or do they use another system? What is the most appropriate way to expose the documentation? Via a Web server/browser, or via a big (several 100MB) help file? Which approach do you take when writing code documentation?

    Read the article

  • Generic software code style enforcer

    - by FuzziBear
    It seems to me to be a fairly common thing to do, where you have some code that you'd like to automatically run through a code style tool to catch when people break your coding style guide(s). Particularly if you're working on code that has multiple languages (which is becoming more common with web-language-x and javascript), you generally want to apply similar code style guides to both and have them enforced. I've done a bit of research, but I've only been able to find tools to enforce code style guidelines (not necessarily applying the code style, just telling you when you break code style guidelines) for a particular language. It would seem to me a reasonably trivial thing to do by just using current IDE rules for syntax highlighting (so that you don't check style guide rules inside quotes or strings, etc) and a whole lot of regexes to enforce some really generic things. Examples: if ( rather than if( checking lines with only whitespace Are there any tools that do this kind of really generic style checking? I'd prefer it to be easily configurable for different languages (because like it or not, some things would just not work cross language) and to add new "rules" to check new things.

    Read the article

  • Legacy Code Retreat Questions

    - by MarkPearl
    I recently heard of the concept of a Legacy Code Retreat. Since I have attended and helped facilitate some normal Code Retreats I thought it might be interesting in trying a Legacy Code Retreat, but I have a few questions on how a legacy CR differs from a normal one. If anyone has attended a Legacy CR and has some suggestions on how best to host these event’s please leave a comment on what has worked for you in the past or if you have any answers to my questions below… Should you restrict the languages that people can do the sessions in? In the normal CR’s I have been involved in the past we have had people attend and code in their programming language of choice. A normal CR lends itself to  this because each session starts with no code. With a legacy CR each session seems to start with an existing code base. Is there some sort of limitation on the languages that people can work in during the sessions? If not, how do you give them a base to start from? What happens as the beginning of each session? In the normal CR that I have attended each session would have a constraint set on it – i.e. no if statements used, no primitives, etc. With a legacy CR it seems more like patterns for refactoring are learned. Does the facilitator explain the pattern used before the session starts or are they just given a code base to start from and an objective to achieve

    Read the article

  • How to refactor a myriad of similar classes

    - by TobiMcNamobi
    I'm faced with similar classes A1, A2, ..., A100. Believe it or not but yeah, there are roughly hundred classes that almost look the same. None of these classes are unit tested (of course ;-) ). Each of theses classes is about 50 lines of code which is not too much by itself. Still this is way too much duplicated code. I consider the following options: Writing tests for A1, ..., A100. Then refactor by creating an abstract base class AA. Pro: I'm (near to totally) safe by the tests that nothing goes wrong. Con: Much effort. Duplication of test code. Writing tests for A1, A2. Abstracting the duplicated test code and using the abstraction to create the rest of the tests. Then create AA as in 1. Pro: Less effort than in 1 but maintaining a similar degree of safety. Con: I find generalized test code weird; it often seems ... incoherent (is this the right word?). Normally I prefer specialized test code for specialized classes. But that requires a good design which is my goal of this whole refactoring. Writing AA first, testing it with mock classes. Then inheriting A1, ..., A100 successively. Pro: Fastest way to eliminate duplicates. Con: Most Ax classes look very much the same. But if not, there is the danger of changing the code by inheriting from AA. Other options ... At first I went for 3. because the Ax classes are really very similar to each other. But now I'm a bit unsure if this is the right way (from a unit testing enthusiast's perspective).

    Read the article

  • Mechanics of reasoning during programming interviews

    - by user129506
    This is not the usual "I don't want to write code during an interview", in this question the assumption is that I need to write code during an interview (think about the level of rewriting the quicksort or mergesort from scratch) I know how the algorithm work or I have a basic idea of how I should start working from there, i.e. I don't remember the algorithm by heart I noticed that even on a whiteboard, I always end up writing bugged code or code that doesn't compile. If there's a typo, whatever I usually live with that.. but when there's a crash due to some uncaught particular case I end up losing confidence in my skills. I realize that perhaps interviewers might want to look at how I write code and/or how I solve problems rather than proof-compiling my whiteboard code, but I'd like to ask how should I approach the above problem in mental terms, i.e. what mental steps should I follow when writing code for an interview with the two bullet points above. There must be a unique and agreed series of steps I should follow to avoid getting stuck/caught into particular exception cases (limit cases) that might end up wasting my time and my energies rather than focusing on the overall algorithm for the general case. I hope I made my point clear

    Read the article

  • Invariant code contracts – using class-wide contracts

    - by DigiMortal
    It is possible to define invariant code contracts for classes. Invariant contracts should always hold true whatever member of class is called. In this posting I will show you how to use invariant code contracts so you understand how they work and how they should be tested. This is my randomizer class I am using to demonstrate code contracts. I added one method for invariant code contracts. Currently there is one contract that makes sure that random number generator is not null. public class Randomizer {     private IRandomGenerator _generator;       private Randomizer() { }       public Randomizer(IRandomGenerator generator)     {         _generator = generator;     }       public int GetRandomFromRangeContracted(int min, int max)     {         Contract.Requires<ArgumentOutOfRangeException>(             min < max,             "Min must be less than max"         );           Contract.Ensures(             Contract.Result<int>() >= min &&             Contract.Result<int>() <= max,             "Return value is out of range"         );           return _generator.Next(min, max);     }       [ContractInvariantMethod]     private void ObjectInvariant()     {         Contract.Invariant(_generator != null);     } } Invariant code contracts are define in methods that have ContractInvariantMethod attribute. Some notes: It is good idea to define invariant methods as private. Don’t call invariant methods from your code because code contracts system does not allow it. Invariant methods are defined only as place where you can keep invariant contracts. Invariant methods are called only when call to some class member is made! The last note means that having invariant method and creating Randomizer object with null as argument does not automatically generate exception. We have to call at least one method from Randomizer class. Here is the test for generator. You can find more about contracted code testing from my posting Code Contracts: Unit testing contracted code. There is also explained why the exception handling in test is like it is. [TestMethod] [ExpectedException(typeof(Exception))] public void Should_fail_if_generator_is_null() {     try     {         var randomizer = new Randomizer(null);         randomizer.GetRandomFromRangeContracted(1, 4);     }     catch (Exception ex)     {         throw new Exception(ex.Message, ex);     } } Try out this code – with unit tests or with test application to see that invariant contracts are checked as soon as you call some member of Randomizer class.

    Read the article

  • Class-Level Model Validation with EF Code First and ASP.NET MVC 3

    - by ScottGu
    Earlier this week the data team released the CTP5 build of the new Entity Framework Code-First library.  In my blog post a few days ago I talked about a few of the improvements introduced with the new CTP5 build.  Automatic support for enforcing DataAnnotation validation attributes on models was one of the improvements I discussed.  It provides a pretty easy way to enable property-level validation logic within your model layer. You can apply validation attributes like [Required], [Range], and [RegularExpression] – all of which are built-into .NET 4 – to your model classes in order to enforce that the model properties are valid before they are persisted to a database.  You can also create your own custom validation attributes (like this cool [CreditCard] validator) and have them be automatically enforced by EF Code First as well.  This provides a really easy way to validate property values on your models.  I showed some code samples of this in action in my previous post. Class-Level Model Validation using IValidatableObject DataAnnotation attributes provides an easy way to validate individual property values on your model classes.  Several people have asked - “Does EF Code First also support a way to implement class-level validation methods on model objects, for validation rules than need to span multiple property values?”  It does – and one easy way you can enable this is by implementing the IValidatableObject interface on your model classes. IValidatableObject.Validate() Method Below is an example of using the IValidatableObject interface (which is built-into .NET 4 within the System.ComponentModel.DataAnnotations namespace) to implement two custom validation rules on a Product model class.  The two rules ensure that: New units can’t be ordered if the Product is in a discontinued state New units can’t be ordered if there are already more than 100 units in stock We will enforce these business rules by implementing the IValidatableObject interface on our Product class, and by implementing its Validate() method like so: The IValidatableObject.Validate() method can apply validation rules that span across multiple properties, and can yield back multiple validation errors. Each ValidationResult returned can supply both an error message as well as an optional list of property names that caused the violation (which is useful when displaying error messages within UI). Automatic Validation Enforcement EF Code-First (starting with CTP5) now automatically invokes the Validate() method when a model object that implements the IValidatableObject interface is saved.  You do not need to write any code to cause this to happen – this support is now enabled by default. This new support means that the below code – which violates one of our above business rules – will automatically throw an exception (and abort the transaction) when we call the “SaveChanges()” method on our Northwind DbContext: In addition to reactively handling validation exceptions, EF Code First also allows you to proactively check for validation errors.  Starting with CTP5, you can call the “GetValidationErrors()” method on the DbContext base class to retrieve a list of validation errors within the model objects you are working with.  GetValidationErrors() will return a list of all validation errors – regardless of whether they are generated via DataAnnotation attributes or by an IValidatableObject.Validate() implementation.  Below is an example of proactively using the GetValidationErrors() method to check (and handle) errors before trying to call SaveChanges(): ASP.NET MVC 3 and IValidatableObject ASP.NET MVC 2 included support for automatically honoring and enforcing DataAnnotation attributes on model objects that are used with ASP.NET MVC’s model binding infrastructure.  ASP.NET MVC 3 goes further and also honors the IValidatableObject interface.  This combined support for model validation makes it easy to display appropriate error messages within forms when validation errors occur.  To see this in action, let’s consider a simple Create form that allows users to create a new Product: We can implement the above Create functionality using a ProductsController class that has two “Create” action methods like below: The first Create() method implements a version of the /Products/Create URL that handles HTTP-GET requests - and displays the HTML form to fill-out.  The second Create() method implements a version of the /Products/Create URL that handles HTTP-POST requests - and which takes the posted form data, ensures that is is valid, and if it is valid saves it in the database.  If there are validation issues it redisplays the form with the posted values.  The razor view template of our “Create” view (which renders the form) looks like below: One of the nice things about the above Controller + View implementation is that we did not write any validation logic within it.  The validation logic and business rules are instead implemented entirely within our model layer, and the ProductsController simply checks whether it is valid (by calling the ModelState.IsValid helper method) to determine whether to try and save the changes or redisplay the form with errors. The Html.ValidationMessageFor() helper method calls within our view simply display the error messages our Product model’s DataAnnotations and IValidatableObject.Validate() method returned.  We can see the above scenario in action by filling out invalid data within the form and attempting to submit it: Notice above how when we hit the “Create” button we got an error message.  This was because we ticked the “Discontinued” checkbox while also entering a value for the UnitsOnOrder (and so violated one of our business rules).  You might ask – how did ASP.NET MVC know to highlight and display the error message next to the UnitsOnOrder textbox?  It did this because ASP.NET MVC 3 now honors the IValidatableObject interface when performing model binding, and will retrieve the error messages from validation failures with it. The business rule within our Product model class indicated that the “UnitsOnOrder” property should be highlighted when the business rule we hit was violated: Our Html.ValidationMessageFor() helper method knew to display the business rule error message (next to the UnitsOnOrder edit box) because of the above property name hint we supplied: Keeping things DRY ASP.NET MVC and EF Code First enables you to keep your validation and business rules in one place (within your model layer), and avoid having it creep into your Controllers and Views.  Keeping the validation logic in the model layer helps ensure that you do not duplicate validation/business logic as you add more Controllers and Views to your application.  It allows you to quickly change your business rules/validation logic in one single place (within your model layer) – and have all controllers/views across your application immediately reflect it.  This help keep your application code clean and easily maintainable, and makes it much easier to evolve and update your application in the future. Summary EF Code First (starting with CTP5) now has built-in support for both DataAnnotations and the IValidatableObject interface.  This allows you to easily add validation and business rules to your models, and have EF automatically ensure that they are enforced anytime someone tries to persist changes of them to a database.  ASP.NET MVC 3 also now supports both DataAnnotations and IValidatableObject as well, which makes it even easier to use them with your EF Code First model layer – and then have the controllers/views within your web layer automatically honor and support them as well.  This makes it easy to build clean and highly maintainable applications. You don’t have to use DataAnnotations or IValidatableObject to perform your validation/business logic.  You can always roll your own custom validation architecture and/or use other more advanced validation frameworks/patterns if you want.  But for a lot of applications this built-in support will probably be sufficient – and provide a highly productive way to build solutions. Hope this helps, Scott P.S. In addition to blogging, I am also now using Twitter for quick updates and to share links. Follow me at: twitter.com/scottgu

    Read the article

  • Convert HTML template (HTML Code) into an image using php library [on hold]

    - by user2727841
    I'm taking input from user through tiny mce editor which is actually html template (HTML Code) and i want to convert that html template (code) into an image using php libaray, How to do it? Is there any API (SDK) OR library for it? well I prefered API (SDK) OR library which actually convert html template (code) into an image... I've searched every where but didn't succeed, now can any one tell me any php library which convert html code into an image... Thanks in advance

    Read the article

  • Debugging OWB generated SAP ABAP code executed through RFC

    - by Anil Menon
    Within OWB if you need to execute ABAP code using RFC you will have to use the SAP Function Module RFC_ABAP_INSTALL_AND_RUN. This function module is specified during the creation of the SAP source location. Usually in a Production environment a copy of this function module is used due to security restrictions. When you execute the mapping by using this Function Module you can’t see the actual ABAP code that is passed on to the SAP system. In case you want to take a look at the code that will be executed on the SAP system you need to use a custom Function Module in SAP. The easiest way to do this is to make a copy of the Function Module RFC_ABAP_INSTALL_AND_RUN and call it say Z_TEST_FM. Then edit the code of the Function Module in SAP as below FUNCTION Z_TEST_FM . DATA: BEGIN OF listobj OCCURS 20. INCLUDE STRUCTURE abaplist. DATA: END OF listobj. DATA: begin_of_line(72). DATA: line_end_char(1). DATA: line_length type I. DATA: lin(72). loop at program. append program-line to WRITES. endloop. ENDFUNCTION. Within OWB edit the SAP Location and use Z_TEST_FM as the “Execution Function Module” instead of  RFC_ABAP_INSTALL_AND_RUN. Then register this location. The Mapping you want to debug will have to be deployed. After deployment you can right click the mapping and click on “Start”.   After clicking start the “Input Parameters” screen will be displayed. You can make changes here if you need to. Check that the parameter BACKGROUND is set to “TRUE”. After Clicking “OK” the log for the execution will be displayed. The execution of Mappings will always fail when you use the above function module. Clicking on the icon “I” (information) the ABAP code will be displayed.   The ABAP code displayed is the code that is passed through the Function Module. You can also find the code by going through the log files on the server which hosts the OWB repository. The logs will be located under <OWB_HOME>/owb/log. Patch #12951045 is recommended while using the SAP Connector with OWB 11.2.0.2. For recommended patches for other releases please check with Oracle Support at http://support.oracle.com

    Read the article

  • Code refactoring with Visual Studio 2010 Part-2

    - by Jalpesh P. Vadgama
    In previous post I have written about Extract Method Code refactoring option. In this post I am going to some other code refactoring features of Visual Studio 2010.  Renaming variables and methods is one of the most difficult task for a developer. Normally we do like this. First we will rename method or variable and then we will find all the references then do remaining over that stuff. This will be become difficult if your variable or method are referenced at so many files and so many place. But once you use refactor menu rename it will be bit Easy. I am going to use same code which I have created in my previous post. I am just once again putting that code here for your reference. using System; namespace CodeRefractoring { class Program { static void Main(string[] args) { string firstName = "Jalpesh"; string lastName = "Vadgama"; Print(firstName, lastName); } private static void Print(string firstName, string lastName) { Console.WriteLine(string.Format("FirstName:{0}", firstName)); Console.WriteLine(string.Format("LastName:{0}", lastName)); Console.ReadLine(); } } } Now I want to rename print method in this code. To rename the method you can select method name and then select Refactor-> Rename . Once I selected Print method and then click on rename a dialog box will appear like following. Now I am renaming this Print method to PrintMyName like following.   Now once you click OK a dialog will appear with preview of code like following. It will show preview of code. Now once you click apply. You code will be changed like following. using System; namespace CodeRefractoring { class Program { static void Main(string[] args) { string firstName = "Jalpesh"; string lastName = "Vadgama"; PrintMyName(firstName, lastName); } private static void PrintMyName(string firstName, string lastName) { Console.WriteLine(string.Format("FirstName:{0}", firstName)); Console.WriteLine(string.Format("LastName:{0}", lastName)); Console.ReadLine(); } } } So that’s it. This will work in multiple files also. Hope you liked it.. Stay tuned for more.. Till that Happy Programming.

    Read the article

  • Choose the Text Editor Used to View Source Code in Internet Explorer

    - by Asian Angel
    Everyone has a favorite text editor that they like to use when viewing or working with source code. If you are unhappy with the default choice in Internet Explorer 8 then join us as we show you how to set up access to your favorite text editor. A Look at Before Here is Internet Explorer on our test system ready to help us view the source code for one of the pages here at the site. Perhaps “Notepad” is your default source code viewer… Or in the case of our test system where “EditPad Lite” was the default due to choices we made while installing it. Choose Your Favorite Text Editor Chances are you have your own personal favorite and want to make it the default source code viewer. To get started go to the “Tools Menu”  and click on “Developer Tools” or press “F12” to access the “Developer Tools Window”. Once you have the “Developer Tools Window” open go to the “File Menu”, then “Customize Internet Explorer View Source”, and click on “Other”. Once you have clicked on “Other” you will see the “Program Directory” for the current default app. Here you can see the “Program Files Folder” for “EditPad Lite”. To change the default app simply browse for the appropriate program folder. On our test system we decided to change the default to “Editra”. Once you have located the program that you want to use click on the “.exe” file for that app and click “Open”. Once you have clicked “Open”, all that is left for you to do is close the “Developer Tools Window”…everything else is already taken care of. And just like that you can be viewing source code with your favorite text editor. Conclusion If you have been unhappy with the default source code viewer in Internet Explorer 8 then you can set up access to your favorite text editor in just a couple of minutes. Nice, quick, and easy the way it ought to be. Thanks to HTG & TinyHacker reader Dwight for the tip! Similar Articles Productive Geek Tips View Webpage Source Code in Your Favorite Text Editor – FirefoxView Webpage Source Code in Tabs in FirefoxEasily View Source of Included Files in FirefoxRemove ISP Text or Corporate Branding from Internet Explorer Title BarRemove PartyPoker (Or Other Items) from the Internet Explorer Tools Menu TouchFreeze Alternative in AutoHotkey The Icy Undertow Desktop Windows Home Server – Backup to LAN The Clear & Clean Desktop Use This Bookmarklet to Easily Get Albums Use AutoHotkey to Assign a Hotkey to a Specific Window Latest Software Reviews Tinyhacker Random Tips Revo Uninstaller Pro Registry Mechanic 9 for Windows PC Tools Internet Security Suite 2010 PCmover Professional Automate Tasks in Linux with Crontab Discover New Bundled Feeds in Google Reader Play Music in Chrome by Simply Dragging a File 15 Great Illustrations by Chow Hon Lam Easily Sync Files & Folders with Friends & Family Amazon Free Kindle for PC Download

    Read the article

  • Improving performance for web scraping code

    - by Pankaj Upadhyay
    I have a website in which the code scrapes other websites for getting the accurate data. While the code works good but there a decent lag in performance because the code firsts downloads the html stream from various sites(some times 9 websites), extracts the relative part and then renders the html page. What should I do to get an optimal performance. Should I change from shared hosting (godaddy) to my own server or it has nothing to do with my hosting and I need to make changes to my code?

    Read the article

  • Announcing Entity Framework Code-First (CTP 5 release)

    In this article, Scott provides a detailed coverage of Entity Framework Code-First CTP 5 release and the features included with the build. He begins with the steps required to install EF Code First. Scott then examines the usage of EF Code First to create a model layer for the Northwind sample database in a series of steps. Towards the end of the article, Scott examines the usage of UI Validation and few addtional EF Code First Improvements shipped with CTP 5.

    Read the article

< Previous Page | 43 44 45 46 47 48 49 50 51 52 53 54  | Next Page >