Search Results

Search found 19923 results on 797 pages for 'instance variables'.

Page 204/797 | < Previous Page | 200 201 202 203 204 205 206 207 208 209 210 211  | Next Page >

• StructureMap resolve dependency through injection instead of service location

  - by Chris Marisic

  In my project I register many ISerializers implementations with the assembly scanner. FWIW this is the code that registers my ISerializers Scan(scanner => { scanner.AssemblyContainingType<ISerializer>(); scanner.AddAllTypesOf<ISerializer>().NameBy(type => type.Name); scanner.WithDefaultConventions(); }); Which then correctly registers ISerializer (...ISerializer) Scoped as: Transient JsonSerializer Configured Instance of ...JsonSerializer BsonSerializer Configured Instance of ...BsonSerializer And so forth. Currently the only way I've been able to figure out how to resolve the serializer I want is to hardcode a service location call with jsonSerializer = ObjectFactory.GetNamedInstance<ISerializer>("JsonSerializer"); Now I know in my class that I specifically want the jsonSerializer so is there a way to configure a rule or similar that says for ISerializer's to connect the named instance based on the property name? So that I could have MySomeClass(ISerializer jsonSerializer, ....) And StructureMap correctly resolve this scenario? Or am I approaching this wrong and perhaps I should just register the concrete type that implements ISerializer and then just specifically use MySomeClass(JsonSerializer jsonSerializer, ....) for something along these lines with the concrete class?

  Read the article

• Factory Method Pattern clarification

  - by nettguy

  My understanding of Factory Method Pattern is (Correct me if i am wrong) Factory Method Pattern "Factory Method allow the client to delegates the product creation (Instance Creation) to the subclass". There are two situation in which we can go for creating Factory Method pattern. (i) When the client is restricted to the product (Instance) creation. (ii) There are multiple products available.But a decision to be made which product instance need to be returned. If you want to create Abstract Method pattern You need to have abstract product Concrete Product Factory Method to return the appropriate product. Example : public enum ORMChoice { L2SQL, EFM, LS, Sonic } //Abstract Product public interface IProduct { void ProductTaken(); } //Concrete Product public class LinqtoSql : IProduct { public void ProductTaken() { Console.WriteLine("OR Mapping Taken:LinqtoSql"); } } //concrete product public class Subsonic : IProduct { public void ProductTaken() { Console.WriteLine("OR Mapping Taken:Subsonic"); } } //concrete product public class EntityFramework : IProduct { public void ProductTaken() { Console.WriteLine("OR Mapping Taken:EntityFramework"); } } //concrete product public class LightSpeed : IProduct { public void ProductTaken() { Console.WriteLine("OR Mapping Taken :LightSpeed"); } } public class Creator { //Factory Method public IProduct ReturnORTool(ORMChoice choice) { switch (choice) { case ORMChoice.EFM:return new EntityFramework(); break; case ORMChoice.L2SQL:return new LinqtoSql(); break; case ORMChoice.LS:return new LightSpeed(); break; case ORMChoice.Sonic:return new Subsonic(); break; default: return null; } } } **Client** Button_Click() { Creator c = new Creator(); IProduct p = c.ReturnORTool(ORMChoice.L2SQL); p.ProductTaken(); } Is my understanding of Factory Method is correct?

  Read the article

• Why can't perfmon see instances of my custom performance counter?

  - by spoulson

  I'm creating some custom performance counters for an application. I wrote a simple C# tool to create the categories and counters. For example, the code snippet below is basically what I'm running. Then, I run a separate app that endlessly refreshes the raw value of the counter. While that runs, the counter and dummy instance are seen locally in perfmon. The problem I'm having is that the monitoring system we use can't see the instances in the multi-instance counter I've created when viewing remotely from another server. When using perfmon to browse the counters, I can see the category and counters, but the instances box is grayed out and I can't even select "All instances", nor can I click "Add". Using other access methods, like [typeperf][1] exhibit similar issues. I'm not sure if this is a server or code issue. This is only reproducible in the production environment where I need it. On my desktop and development servers, it works great. I'm a local admin on all servers. CounterCreationDataCollection collection = new CounterCreationDataCollection(); var category_name = "My Application"; var counter_name = "My counter name"; CounterCreationData ccd = new CounterCreationData(); ccd.CounterType = PerformanceCounterType.RateOfCountsPerSecond64; ccd.CounterName = counter_name; ccd.CounterHelp = counter_name; collection.Add(ccd); PerformanceCounterCategory.Create(category_name, category_name, PerformanceCounterCategoryType.MultiInstance, collection); Then, in a separate app, I run this to generate dummy instance data: var pc = new PerformanceCounter(category_name, counter_name, instance_name, false); while (true) { pc.RawValue = 0; Thread.Sleep(1000); }

  Read the article

• How do attribute classes work?

  - by AaronLS

  My searches keep turning up only guides explaining how to use and apply attributes to a class. I want to learn how to create my own attribute classes and the mechanics of how they work. How are attribute classes instantiated? Are they instantiated when the class they are applied to is instantiated? Is one instantiated for each class instantiated that it is applied to? E.g. if I apply the SerializableAttribute class to a MyData class, and I instantiate 5 MyData instances, will there be 5 instances of the SerializbleAttribute class created behind the scenes? Or is there just one instance shared between all of them? How do attribute class instances access the class they are associated with? How does a SerializableAttribute class access the class it is applied to so that it can serialize it's data? Does it have some sort of SerializableAttribute.ThisIsTheInstanceIAmAppliedTo property? :) Or does it work in the reverse direction that whenever I serialize something, the Serialize function I pass the MyClass instance to will reflectively go through the Attributes and find the SerialiableAttribute instance?

  Read the article

• instantiate python object within a c function called via ctypes

  - by gwk

  My embedded Python 3.3 program segfaults when I instantiate python objects from a c function called by ctypes. After setting up the interpreter, I can successfully instantiate a python Int (as well as a custom c extension type) from c main: #import <Python/Python.h> #define LOGPY(x) \ { fprintf(stderr, "%s: ", #x); PyObject_Print((PyObject*)(x), stderr, 0); fputc('\n', stderr); } // c function to be called from python script via ctypes. void instantiate() { PyObject* instance = PyObject_CallObject((PyObject*)&PyLong_Type, NULL); LOGPY(instance); } int main(int argc, char* argv[]) { Py_Initialize(); instantiate(); // works fine // run a script that calls instantiate() via ctypes. FILE* scriptFile = fopen("emb.py", "r"); if (!scriptFile) { fprintf(stderr, "ERROR: cannot open script file\n"); return 1; } PyRun_SimpleFileEx(scriptFile, scriptPath, 1); // close on completion return 0; } I then run a python script using PyRun_SimpleFileEx. It appears to run just fine, but when it calls instantiate() via ctypes, the program segfaults inside PyObject_CallObject: import ctypes as ct dy = ct.CDLL('./emb') dy.instantiate() # segfaults lldb output: instance: 0 Process 52068 stopped * thread #1: tid = 0x1c03, 0x000000010000d3f5 Python`PyObject_Call + 69, stop reason = EXC_BAD_ACCESS (code=1, address=0x18) frame #0: 0x000000010000d3f5 Python`PyObject_Call + 69 Python`PyObject_Call + 69: -> 0x10000d3f5: movl 24(%rax), %edx 0x10000d3f8: incl %edx 0x10000d3fa: movl %edx, 24(%rax) 0x10000d3fd: leaq 2069148(%rip), %rax ; _Py_CheckRecursionLimit (lldb) bt * thread #1: tid = 0x1c03, 0x000000010000d3f5 Python`PyObject_Call + 69, stop reason = EXC_BAD_ACCESS (code=1, address=0x18) frame #0: 0x000000010000d3f5 Python`PyObject_Call + 69 frame #1: 0x00000001000d5197 Python`PyEval_CallObjectWithKeywords + 87 frame #2: 0x0000000201100d8e emb`instantiate + 30 at emb.c:9 Why does the call to instantiate() fail from ctypes only? The function only crashes when it calls into the python lib, so perhaps some interpreter state is getting munged by the ctypes FFI call?

  Read the article

• WMI Query Script as a Job

  - by Kenneth

  I have two scripts. One calls the other with a list of servers as parameters. The second query is designed to execute a WMI query. When I run it manually, it does this perfectly. When I try to run it as a job it hangs forever and I have to remove it. For the sake of space here is the relevant part of the calling script: ProcessServers.ps1 Start-Job -FilePath .\GetServerDetailsLight.ps1 -ArgumentList $sqlsrv,$destdb,$server,$instance GetServerDetailsLight.ps1 param($sqlsrv,$destdb,$server,$instance) $password = get-content C:\SQLPS\auth.txt | convertto-securestring $credentials = new-object -typename System.Management.Automation.PSCredential -argumentlist "DOMAIN\MYUSER",$password [System.Reflection.Assembly]::LoadWithPartialName('Microsoft.SqlServer.SMO') $box_id = 0; if ($sqlsrv.length -eq 0) { write-output "No data passed" break } function getinfo { param( [string]$svr, [string]$inst ) "Entered GetInfo with: $svr,$inst" $cs = get-wmiobject win32_operatingsystem -computername $svr -credential $credentials -authentication 6 -Verbose -Debug | select Name, Model, Manufacturer, Description, DNSHostName, Domain, DomainRole, PartOfDomain, NumberOfProcessors, SystemType, TotalPhysicalMemory, UserName, Workgroup write-output "WMI Results: $cs" } getinfo $server $instance write-output "Complete" Executed as a job it will show as 'running' forever: PS C:\sqlps> Start-Job -FilePath .\GetServerDetailsLight.ps1 -ArgumentList DBSERVER,LOGDB,SERVER01,SERVER01 Id Name State HasMoreData Location Command -- ---- ----- ----------- -------- ------- 21 Job21 Running True localhost param($sqlsrv,$destdb,... GAC Version Location --- ------- -------- True v2.0.50727 C:\WINDOWS\assembly\GAC_MSIL\Microsoft.SqlServer.Smo\10.0.0.0__89845dcd8080cc91\Microsoft.SqlServer.Smo.dll getinfo MSDCHR01 MSDCHR01 Entered GetInfo with: SERVER01,SERVER01 The last output I ever get is the 'Entered GetInfo with: SERVER01,SERVER01'. If I run it manually like so: PS C:\sqlps> .\GetServerDetailsLight.ps1 DBSERVER LOGDB SERVER01 SERVER01 The WMI query executes just as expected. I am trying to determine why this is, or at least a useful way to trap errors from within jobs. Thanks!

  Read the article

• Single Responsibility Principle usage how can i call sub method correctly?

  - by Phsika

  i try to learn SOLID prencibles. i writed two type of code style. which one is : 1)Single Responsibility Principle_2.cs : if you look main program all instance generated from interface 1)Single Responsibility Principle_3.cs : if you look main program all instance genareted from normal class My question: which one is correct usage? which one can i prefer? namespace Single_Responsibility_Principle_2 { class Program { static void Main(string[] args) { IReportManager raporcu = new ReportManager(); IReport wordraporu = new WordRaporu(); raporcu.RaporHazirla(wordraporu, "data"); Console.ReadKey(); } } interface IReportManager { void RaporHazirla(IReport rapor, string bilgi); } class ReportManager : IReportManager { public void RaporHazirla(IReport rapor, string bilgi) { rapor.RaporYarat(bilgi); } } interface IReport { void RaporYarat(string bilgi); } class WordRaporu : IReport { public void RaporYarat(string bilgi) { Console.WriteLine("Word Raporu yaratildi:{0}",bilgi); } } class ExcellRaporu : IReport { public void RaporYarat(string bilgi) { Console.WriteLine("Excell raporu yaratildi:{0}",bilgi); } } class PdfRaporu : IReport { public void RaporYarat(string bilgi) { Console.WriteLine("pdf raporu yaratildi:{0}",bilgi); } } } Second 0ne all instance genareted from normal class namespace Single_Responsibility_Principle_3 { class Program { static void Main(string[] args) { WordRaporu word = new WordRaporu(); ReportManager manager = new ReportManager(); manager.RaporHazirla(word,"test"); } } interface IReportManager { void RaporHazirla(IReport rapor, string bilgi); } class ReportManager : IReportManager { public void RaporHazirla(IReport rapor, string bilgi) { rapor.RaporYarat(bilgi); } } interface IReport { void RaporYarat(string bilgi); } class WordRaporu : IReport { public void RaporYarat(string bilgi) { Console.WriteLine("Word Raporu yaratildi:{0}",bilgi); } } class ExcellRaporu : IReport { public void RaporYarat(string bilgi) { Console.WriteLine("Excell raporu yaratildi:{0}",bilgi); } } class PdfRaporu : IReport { public void RaporYarat(string bilgi) { Console.WriteLine("pdf raporu yaratildi:{0}",bilgi); } } }

  Read the article

• swf listens to XML, AS3

  - by VideoDnd

  My swf listens to XML from a socket and document. How do I get 'my variables' to grab XML from the socket instead of the XML document? PURPOSE My purpose is to control variables with a XML Socket Server. I hope my question is clear, but ask if there's any questions. EXAMPLE Flash File import flash.net.*; import flash.display.*; import flash.events.*; import flash.system.Security; import flash.utils.Timer; import flash.events.TimerEvent; //MY VARIABLES, LINE 8-12 var timer:Timer = new Timer(10); var myString:String = ""; var count:int = 0; var myStg:String = ""; var fcount:int = 0; var xml_s=new XMLSocket(); xml_s.addEventListener(Event.CONNECT, socket_event_catcher);//OnConnect// xml_s.addEventListener(Event.CLOSE, socket_event_catcher);//OnDisconnect// xml_s.addEventListener(IOErrorEvent.IO_ERROR, socket_event_catcher);//Unable To Connect// xml_s.addEventListener(DataEvent.DATA, socket_event_catcher);//OnDisconnect// xml_s.connect("localhost", 1999); function socket_event_catcher(Event):void { switch (Event.type) { case 'ioError' : trace("ioError: " + Event.text);//Unable to Connect :(// break; case 'connect' : trace("Connection Established!");//Connected :)// break; case 'data' : trace("Received Data: " + Event.data); //var myXML:XML=new XML(Event.data); //trace("myXML.body.file: " + myXML.body.file); //var myLoader:String=myXML.body.file; //var urlReq:URLRequest=new URLRequest(myLoader); //trace("file to load URL: " + urlReq); break; case 'close' : trace("Connection Closed!");//OnDisconnect :( // xml_s.close(); break; } } //LOAD XML var myXML:XML; var myLoader:URLLoader = new URLLoader(); myLoader.load(new URLRequest("time.xml")); myLoader.addEventListener(Event.COMPLETE, processXML); //var myXML:XML=new XML(Event.data); //trace("myXML.body.file: " + myXML.body.file); //var DOINK:String=myXML.body.file; //var urlReq:URLRequest=new URLRequest(DOINK); //trace("file to load URL: " + urlReq); //PARSE XML function processXML(e:Event):void { myXML = new XML(e.target.data); trace(myXML.COUNT.text()); //-77777 //grab the data as a string myString = myXML.COUNT.text() //grab the data as an int count = int(myXML.COUNT.text()); //grab the data as a string myString = myXML.COUNT.text() //grab the data as an int count = int(myXML.COUNT.text()); //grab the data as a string myStg = myXML.COUNT.text() //grab the data as an int fcount = int(myXML.COUNT.text()); //grab the data as a string myStg = myXML.COUNT.text() //grab the data as an int fcount = int(myXML.COUNT.text()); trace("String: ", myString); trace("Int: ", count); trace(count - 1); //just to show you that it's a number that you can do math with (-77778) //TEXT var text:TextField = new TextField(); text.text = myString; addChild(text); } Ruby Server 'Snippet' msg1 = {"msg" => {"head" => {"type" => "frctl", "seq_no" => seq_no, "version" => 1.0}, "SESSION" => {"text" => "88888", "timer" => -1000, "count" => 10, "fcount" => "10"}}} XML <?xml version="1.0" encoding="utf-8"?> <SESSION> <TIMER TITLE="speed">100</TIMER> <COUNT TITLE="starting position">88888</COUNT> <FCOUNT TITLE="ramp">1000</FCOUNT> </SESSION> ENVIROMENT AS3 Ruby 186-25 PROBLEM Coding errors "coercion of value"

  Read the article

• Proper Usage of SqlConnection in .NET

  - by Jojo

  Hi guys, I just want an opinion on the proper usage or a proper design with regards to using SqlConnection object. Which of the 2 below is the best use: A data provider class whose methods (each of them) contain SqlConnection object (and disposed when done). Like: IList<Employee> GetAllEmployees() { using (SqlConnection connection = new SqlConnection(this.connectionString)) { // Code goes here... } } Employee GetEmployee(int id) { using (SqlConnection connection = new SqlConnection(this.connectionString)) { // Code goes here... } } or SqlConnection connection; // initialized in constructor IList<Employee> GetAllEmployees() { this.TryOpenConnection(); // tries to open member SqlConnection instance // Code goes here... this.CloseConnection(); // return } Employee GetEmployee(int id) { this.TryOpenConnection(); // tries to open member SqlConnection instance // Code goes here... this.CloseConnection(); // return } Or is there a better approach than this? I have a focused web crawler type of application and this application will crawl 50 or more websites simultaneously (multithreaded) with each website contained in a crawler object and each crawler object has an instance of a data provider class (above). Please advise. Thanks.

  Read the article

• Java many to many association map

  - by Raphael Jolivet

  Hi, I have to classes, ClassA and ClassB and a "many to many" AssociationClass. I want to use a structure to hold the associations between A and B such as I can know, for each instance of A or B, which are their counterparts. I thought of using a Hashmap, with pair keys: Hasmap<Pair<ClassA, ClassB>, AssociationClass> associations; This way, I can add and remove an association between two instances of ClassA and ClassB, and I can query a relation for two given instances. However, I miss the feature of getting all associations defined for a given instance of ClassA or ClassB. I could do it by brute force and loop over all keys of the map to search for associations between a given instance, but this is inefficient and not elegant. Do you know of any data structure / free library that enables this ? I don't want to reinvent the wheel. Thanks in advance for your help, Raphael NB: This is not a "database" question. These objects are pure POJO used for live computation, I don't need persistence stuff.

  Read the article

• My IDE is showing "undeclared FileNotFoundException must be caught or thrown"

  - by Dan Czarnecki

  I am having the following issue above. I have tried actually putting a try-catch statement into the code as you will see below, but I can't get the compiler to get past that. import java.io.*; public class DirectoryStatistics extends DirectorySize { /* Dan Czarnecki October 24, 2013 Class variables: private File directory A File object that holds the pathname of the directory to look in private long sizeInBytes A variable of type long that holds the size of a file/directory (in bytes) private long fileCount A variable of type long that holds the number of files in a directory Constructors: public DirectoryStatistics(File startingDirectory) throws FileNotFoundException Creates a DirectoryStatistics object, given a pathname (inherited from DirectorySize class), and has 3 instance variables that hold the directory to search in, the size of each file (in bytes), and the number of files within the directory Modification history: October 24, 2013 Original version of class */ private File directory; private long sizeInBytes; private long fileCount; public DirectoryStatistics(File startingDirectory) throws FileNotFoundException { super(startingDirectory); try { if(directory == null) { throw new IllegalArgumentException("null input"); } if(directory.isDirectory() == false) { throw new FileNotFoundException("the following input is not a directory!"); } } catch(IOException ioe) { System.out.println("You have not entered a directory. Please try again."); } } public File getDirectory() { return this.directory; } public long getSizeInBytes() { return this.sizeInBytes; } public long getFileCount() { return this.fileCount; } public long setFileCount(long size) { fileCount = size; return size; } public long setSizeInBytes(long size) { sizeInBytes = size; return size; } public void incrementFileCount() { fileCount = fileCount + 1; } public void addToSizeInBytes(long addend) { sizeInBytes = sizeInBytes + addend; } public String toString() { return "Directory" + this.directory + "Size (in bytes) " + this.sizeInBytes + "Number of files: " + this.fileCount; } public int hashCode() { return this.directory.hashCode(); } public boolean equals(DirectoryStatistics other) { return this.equals(other); } } import java.io.*; import java.util.*; public class DirectorySize extends DirectoryProcessor { /* Dan Czarnecki October 17, 2013 Class variables: private Vector<Long> directorySizeList Variable of type Vector<Long> that holds the total file size of files in that directory as well as files within folders of that directory private Vector<File> currentFile Variable of type Vector<File> that holds the parent directory Constructors: public DirectorySize(File startingDirectory) throws FileNotFoundException Creates a DirectorySize object, takes in a pathname (inherited from DirectoryProcessor class, and has a single vector of a DirectoryStatistics object to hold the files and folders within a directory Modification History October 17, 2013 Original version of class Implemented run() and processFile() methods */ private Vector<DirectoryStatistics> directory; /* private Vector<Long> directorySizeList; private Vector<File> currentFile; */ public DirectorySize(File startingDirectory) throws FileNotFoundException { super(startingDirectory); directory = new Vector<DirectoryStatistics>(); } public void processFile(File file) { DirectoryStatistics parent; int index; File parentFile; System.out.println(file.getName()); System.out.println(file.getParent()); parentFile = file.getParentFile(); parent = new DirectoryStatistics(parentFile); System.out.println(parent); parent.equals(parent); index = directory.indexOf(parent); if(index == 0) { directory.elementAt(index).addToSizeInBytes(file.length()); directory.elementAt(index).incrementFileCount(); } if(index < 0) { directory.addElement(parent); directory.lastElement().setSizeInBytes(file.length()); directory.lastElement().incrementFileCount(); } Could someone tell me why I'm getting this issue?

  Read the article

• Has any one used client_side_validations gem with Chosen.js dropdown?

  - by Abid

  I am using chosen.js (http://harvesthq.github.com/chosen/). I was wondering if anyone has been able to use chosen select boxes and client_side_validations together. The issue is that when we use chosen it hides the original select element and renders its own dropdown instead, and when we focus out the validation isn't called and also when the validation message is shown it is shown with the original select element so positioning of the error isnt also correct. What could be a good way to handle this, My be we can change some code inside ActionView::Base.field_error_proc which currently looks something like ActionView::Base.field_error_proc = Proc.new do |html_tag, instance| unless html_tag =~ /^<label/ %{<div class="field_with_errors">#{html_tag}<label for="#{instance.send(:tag_id)}" class="message">#{instance.error_message.first}</label></div>}.html_safe else %{<div class="field_with_errors">#{html_tag}</div>}.html_safe end end Any ideas ? Edit 1: I have the following solution that is working for me now. applied a class "chzn-dropdown" to all my selects that were being displayed by chosen used the following callback provided by client_side_validations Gem clientSideValidations.callbacks.element.fail = function(element, message, callback) { if (element.data('valid') !== false) { if(element.hasClass('dropdown')){ chzn_element = $('#'+element.attr('id')+'_chzn'); console.log(chzn_element); chzn_element.append(""+message+""); } else{ callback(); } } } Thanks

  Read the article

• ReportServer 2005 Custom Assembly Error

  - by user752083

  We have a reportserver on sql server 2005, it has previously been working on computer X which we are replacing with a computer Y. Computer X only had one default sql instance as our test environment, machine Y is a new machine with 2 sql instances, Y\TEST and Y\DEV. Both machines run Windows Server 2003 and Both have Sql Server 2005 installed together with Report Server We have not currently done any work on the DEV instance, just on the TEST instance. The reportserver is installed for TEST. SSRS previously worked as intended on X machine, and on Y\TEST its working for reports not using any custom code. However for some of the reports we are loading a custom assembly Localization. This assembly currently exists in following folders on server: C:\Program Files\Microsoft Visual Studio 8\Common7\IDE\PublicAssemblies C:\Program Files\Microsoft Visual Studio 8\Common7\IDE\PrivateAssemblies C:\Program Files\Microsoft SQL Server\MSSQL.2\Reporting Services\ReportServer\bin Also in rssrvpolicy.config, the entry for Report_Expressions_Default_Permissions has been changed from Execution to FullTrust (Although this was not necessary on the machine X). When attempting to upload the rdl files through the web interface, we get the following errors: Error while loading code module: ‘Localization, Version=1.0.0.0, Culture=neutral, PublicKeyToken=e302ddd55ecd694a’. Details: Could not load file or assembly 'Localization, Version=1.0.0.0, Culture=neutral, PublicKeyToken=e302ddd55ecd694a' or one of its dependencies. The system cannot find the file specified. (rsErrorLoadingCodeModule) Get Online Help There is an error on line 14 of custom code: [BC30451] Name 'Localization' is not declared. (rsCompilerErrorInCode) Get Online Help Does anyone know any other places with potential errors?

  Read the article

• Custom model validation of dependent properties using Data Annotations

  - by Darin Dimitrov

  Since now I've used the excellent FluentValidation library to validate my model classes. In web applications I use it in conjunction with the jquery.validate plugin to perform client side validation as well. One drawback is that much of the validation logic is repeated on the client side and is no longer centralized at a single place. For this reason I'm looking for an alternative. There are many examples out there showing the usage of data annotations to perform model validation. It looks very promising. One thing I couldn't find out is how to validate a property that depends on another property value. Let's take for example the following model: public class Event { [Required] public DateTime? StartDate { get; set; } [Required] public DateTime? EndDate { get; set; } } I would like to ensure that EndDate is greater than StartDate. I could write a custom validation attribute extending ValidationAttribute in order to perform custom validation logic. Unfortunately I couldn't find a way to obtain the model instance: public class CustomValidationAttribute : ValidationAttribute { public override bool IsValid(object value) { // value represents the property value on which this attribute is applied // but how to obtain the object instance to which this property belongs? return true; } } I found that the CustomValidationAttribute seems to do the job because it has this ValidationContext property that contains the object instance being validated. Unfortunately this attribute has been added only in .NET 4.0. So my question is: can I achieve the same functionality in .NET 3.5 SP1? UPDATE: It seems that FluentValidation already supports clientside validation and metadata in ASP.NET MVC 2. Still it would be good to know though if data annotations could be used to validate dependent properties.

  Read the article

• Core Data - 'calculated' attributes

  - by nephilim

  I have two entities: A and B A has two properties from and to, both pointing to the B entity. B as a fetched property to A with predicate from == $FETCH_SOURCE or to = $FETCH_SOURCE -- (from) -> A -- (to) -> B <- (As) -- In my application I select a certain B instance, and then show all of its A instances. Now, in my table the columns are bound to an array controller containing the selected A instances. I want to 'merge' the from and to columns. I already know one of the columns will be equal to the selected B instance, so now I'm only interested in the second value. The options I see: create a custom class for the B entity and create a method that returns either value. It should somehow be able to retrieve which B instance is currently selected. create a custom DataSource. Most columns are still using bindings, so then we'd have to access the NSArrayController's array so we're sure we have the right object. create a custom DataSource, remove the NSArrayController and do all the Core Data stuff ourselves. Is there any 'right' way to solve this?

  Read the article

• Clearing input text feilds when clicked on in Flash (AS 2.0)

  - by rickstyphilis

  I have a problem where I want a text field that by default has the word NAME in it, to become empty when a user clicks on it. The text field has the instance name 'nam' and is inside a movie with the instance name 'input_text'. I've searched around and found samples of code where everyone keeps suggesting this: textboxinstancename.onSetFocus = function() { textboxinstancename.text = ""; }; should work. It seems to work for everyone else but me. I've tried using the following on the first frame of the 'input_text' movie with no luck: this.input_text.nam.onSetFocus = function() { this.input_text.nam.text = "" } I've tried putting this on the first frame of the scene, again with no result: _root.input_text.nam.onSetFocus = function() { _root.input_text.nam.text = "" } I've tried this in the same manner as the last respectively with both 'this' on the instance and '_root' on the scene (denoted by x): x.input_text.nam.onSetFocus = function() { if (x.input_text.nam.text == "NAME") { x.input_text.nam.text = ""; } }; Still no luck. Can anyone tell me what I might be doing wrong?

  Read the article

• Thoughts on GoGrid vs EC2

  - by Jason

  I am currently hosting my SaaS application at GoGrid (Microsoft stack). Here's what I have: Database Server - physical box, 12 GB RAM, 2 X Quad Core CPU (2.13 GHz Xeon E5506) 2 Web / App servers - cloud servers, 2 GB RAM, 2 VCPUs 300 GB monthly bandwidth I am paying around $900 / month for this. My web / app servers are busting at the seams and need to be upgraded to 4 GB of RAM. I also need a firewall, and GoGrid just added this service for an additional $200. After the upgrade, I will be paying around $1,400. I started looking at Amazon EC2, specifically this config: Database server - "High Memory Double Extra Large Instance" - 34 GB RAM, 13 EC2 compute units 2 Web / App servers - "Large Instance" - 7.5 GB RAM, 4 EC2 compute units If I go with 1 year reserved instances, my upfront cost would be $4,500 and my monthly would be $700. This comes to $1,075 / month when amortized. Amazon also includes a firewall for free. Here are my questions: Do any of you have experience running a database (especially SQL Server) on an EC2 instance? How did it perform compared to a dedicated machine? One of my major concerns is with disk I/O. Amazon's description of a compute unit is fairly vague. Any ideas on how the CPU performance on the database servers would compare? I am hoping that the Amazon solution will provide significantly better performance than my current or even improved GoGrid setup. Having a virtual database server would also be nice in terms of availability. Right now I would be in serious trouble if I had any hardware issues. Thanks for any insight...

  Read the article

• Password hashing, salt and storage of hashed values

  - by Jonathan Leffler

  Suppose you were at liberty to decide how hashed passwords were to be stored in a DBMS. Are there obvious weaknesses in a scheme like this one? To create the hash value stored in the DBMS, take: A value that is unique to the DBMS server instance as part of the salt, And the username as a second part of the salt, And create the concatenation of the salt with the actual password, And hash the whole string using the SHA-256 algorithm, And store the result in the DBMS. This would mean that anyone wanting to come up with a collision should have to do the work separately for each user name and each DBMS server instance separately. I'd plan to keep the actual hash mechanism somewhat flexible to allow for the use of the new NIST standard hash algorithm (SHA-3) that is still being worked on. The 'value that is unique to the DBMS server instance' need not be secret - though it wouldn't be divulged casually. The intention is to ensure that if someone uses the same password in different DBMS server instances, the recorded hashes would be different. Likewise, the user name would not be secret - just the password proper. Would there be any advantage to having the password first and the user name and 'unique value' second, or any other permutation of the three sources of data? Or what about interleaving the strings? Do I need to add (and record) a random salt value (per password) as well as the information above? (Advantage: the user can re-use a password and still, probably, get a different hash recorded in the database. Disadvantage: the salt has to be recorded. I suspect the advantage considerably outweighs the disadvantage.) There are quite a lot of related SO questions - this list is unlikely to be comprehensive: Encrypting/Hashing plain text passwords in database Secure hash and salt for PHP passwords The necessity of hiding the salt for a hash Clients-side MD5 hash with time salt Simple password encryption Salt generation and Open Source software I think that the answers to these questions support my algorithm (though if you simply use a random salt, then the 'unique value per server' and username components are less important).

  Read the article

• Associating an object with another object for GC clearup

  - by thecoop

  Is there any way of associating an object instance (object A) with a second object (object B) in a generalised way, so that when B gets collected A becomes eligable for collection? The same behaviour that would happen if B had an instance variable pointing to A, but without explicitly changing the class definition of B, and being able to do this in a dynamic way? The same sort of effect could be done by using the Component.Disposed event in a funky way, but I don't want to make B disposable EDIT I'm basically creating a cache of objects that are associated with a single 'root' object, and I don't want the cache to be static, as there can be lots of root objects using different caches, so lots of memory will be used up when a root object is no longer used but the cached objects are still around. So, I want a collection of cached objects to be associated with each 'root' object, without changing the root object definition. Sort of like metadata of an extra object reference attached to each root object instance. That way, each collection will get collected when the root object is collected, and not hang around like they would if a static cache was used.

  Read the article

• Extension methods for encapsulation and reusability

  - by tzaman

  In C++ programming, it's generally considered good practice to "prefer non-member non-friend functions" instead of instance methods. This has been recommended by Scott Meyers in this classic Dr. Dobbs article, and repeated by Herb Sutter and Andrei Alexandrescu in C++ Coding Standards (item 44); the general argument being that if a function can do its job solely by relying on the public interface exposed by the class, it actually increases encapsulation to have it be external. While this confuses the "packaging" of the class to some extent, the benefits are generally considered worth it. Now, ever since I've started programming in C#, I've had a feeling that here is the ultimate expression of the concept that they're trying to achieve with "non-member, non-friend functions that are part of a class interface". C# adds two crucial components to the mix - the first being interfaces, and the second extension methods: Interfaces allow a class to formally specify their public contract, the methods and properties that they're exposing to the world. Any other class can choose to implement the same interface and fulfill that same contract. Extension methods can be defined on an interface, providing any functionality that can be implemented via the interface to all implementers automatically. And best of all, because of the "instance syntax" sugar and IDE support, they can be called the same way as any other instance method, eliminating the cognitive overhead! So you get the encapsulation benefits of "non-member, non-friend" functions with the convenience of members. Seems like the best of both worlds to me; the .NET library itself providing a shining example in LINQ. However, everywhere I look I see people warning against extension method overuse; even the MSDN page itself states: In general, we recommend that you implement extension methods sparingly and only when you have to. So what's the verdict? Are extension methods the acme of encapsulation and code reuse, or am I just deluding myself?

  Read the article

• Getting the name of a child class in the parent class (static context)

  - by Benoit Myard

  Hi everybody, I'm building an ORM library with reuse and simplicity in mind; everything goes fine except that I got stuck by a stupid inheritance limitation. Please consider the code below: class BaseModel { /* * Return an instance of a Model from the database. */ static public function get (/* varargs */) { // 1. Notice we want an instance of User $class = get_class(parent); // value: bool(false) $class = get_class(self); // value: bool(false) $class = get_class(); // value: string(9) "BaseModel" $class = __CLASS__; // value: string(9) "BaseModel" // 2. Query the database with id $row = get_row_from_db_as_array(func_get_args()); // 3. Return the filled instance $obj = new $class(); $obj->data = $row; return $obj; } } class User extends BaseModel { protected $table = 'users'; protected $fields = array('id', 'name'); protected $primary_keys = array('id'); } class Section extends BaseModel { // [...] } $my_user = User::get(3); $my_user->name = 'Jean'; $other_user = User::get(24); $other_user->name = 'Paul'; $my_user->save(); $other_user->save(); $my_section = Section::get('apropos'); $my_section->delete(); Obviously, this is not the behavior I was expecting (although the actual behavior also makes sense).. So my question is if you guys know of a mean to get, in the parent class, the name of child class.

  Read the article

• Coldfusion "Routines cannot be declared more than once"

  - by Nicholas

  We have the following code in our Application.cfc: <cffunction name="onError" returnType="void" output="false"> <cfargument name="exception" required="true"> <cfargument name="eventname" type="string" required="true"> <cfset cfcatch = exception> <cfinclude template="standalone/errors/error.cfm"> </cffunction> Within the error.cfm page we have this code (I didn't write it): <cfscript> function GetCurrentURL() { var theURL = "http"; if (cgi.https EQ "on" ) theURL = "#TheURL#s"; theURL = theURL & "://#cgi.server_name#"; if(cgi.server_port neq 80) theURL = theURL & ":#cgi.server_port#"; theURL = theURL & "#cgi.path_info#"; if(len(cgi.query_string)) theURL = theURL & "?#cgi.query_string#"; return theURL; } </cfscript> This is all part of a script that puts together bunches of details about the error and records it to the database. When an error occurs, we receive the message "The routine GetCurrentURL has been declared twice in different templates." However, I have searched the entire codebase in several different ways and found "GetCurrentURL" used only twice, both times in error.cfm. The first time is the declaration, and the second is actual use. So I'm not sure why CF is saying "in different templates". My next thought was that the problem is a recursive call, and that error.cfm is erroring and calling itself, so I attempted these two changes, either of which should have resolved the issue and unmasked the real error: <cfif StructKeyExists(variables,"GetCurrentURL") IS "NO"> <cfscript> function GetCurrentURL() { var theURL = "http"; if (cgi.https EQ "on" ) theURL = "#TheURL#s"; theURL = theURL & "://#cgi.server_name#"; if(cgi.server_port neq 80) theURL = theURL & ":#cgi.server_port#"; theURL = theURL & "#cgi.path_info#"; if(len(cgi.query_string)) theURL = theURL & "?#cgi.query_string#"; return theURL; } </cfscript> </cfif> And: <cfscript> if (!StructKeyExists(variables,"GetCurrentURL")) { function GetCurrentURL() { var theURL = "http"; if (cgi.https EQ "on" ) theURL = "#TheURL#s"; theURL = theURL & "://#cgi.server_name#"; if(cgi.server_port neq 80) theURL = theURL & ":#cgi.server_port#"; theURL = theURL & "#cgi.path_info#"; if(len(cgi.query_string)) theURL = theURL & "?#cgi.query_string#"; return theURL; } } </cfscript> Neither worked. I also tried adding this to the page just before the function call: <cfoutput>"#StructKeyExists(variables,"GetCurrentURL")#"</cfoutput> It caused the word "YES" to be printed on screen. This indicates that the above should work, as clearly the contents of the if statement will evaluate to "YES", and thus the if statement will evaluate to false, and thus the function will not be declared, and thus I will retain my sanity. But for some reason this problem persists. Any thoughts on what might be occuring or how to troubleshoot next? I'm stuck at this point.

  Read the article

• What is the relation between ContentPane and JPanel?

  - by Roman

  I found one example in which buttons are added to panels (instances of JPanel) then panels are added to the the containers (instances generated by getContentPane) and then containers are, by the construction, included into the JFrame (the windows). I tried two things: I got rid of the containers. In more details, I added buttons to a panel (instance of JPanel) and then I added the panel to the windows (instance of JFrame). It worked fine. I got rid of the panels. In more details, I added buttons directly to the container and then I added the container to the window (instance of JFrame). So, I do not understand two things. Why do we have two competing mechanism to do the same things. What is the reason to use containers in combination with the panels (JPanel)? (For example, what for we include buttons in JPanels and then we include JPanels in the Containers). Can we include JPanel in JPanel? Can we include a container in container?

  Read the article

• OOP - Handling Automated Instances of a Class - PHP

  - by dscher

  This is a topic that, as a beginner to PHP and programming, sort of perplexes me. I'm building a stockmarket website and want users to add their own stocks. I can clearly see the benefit of having each stock be a class instance with all the methods of a class. What I am stumped on is the best way to give that instance a name when I instantiate it. If I have: class Stock() { ....doing stuff..... } what is the best way to give my instances of it a name. Obviously I can write: $newStock = new Stock(); $newStock.getPrice(); or whatever, but if a user adds a stock via the app, where can the name of that instance come from? I guess that there is little harm in always creating a new child with $newStock = new Stock() and then storing that to the DB which leads me to my next question! What would be the best way to retrieve 20 user stocks(for example) into instances of class Stock()? Do I need to instantiate 20 new instances of class Stock() every time the user logs in or is there something I'm missing? I hope someone answers this and more important hope a bunch of people answer this and it somehow helps someone else who is having a hard time wrapping their head around what probably leads to a really elegant solution. Thanks guys!

  Read the article

• Why does this extension method throw a NullReferenceException in VB.NET?

  - by Dan

  From previous experience I had been under the impression that it's perfectly legal (though perhaps not advisable) to call extension methods on a null instance. So in C#, this code compiles and runs: // code in static class static bool IsNull(this object obj) { return obj == null; } // code elsewhere object x = null; bool exists = !x.IsNull(); However, I was just putting together a little suite of example code for the other members of my development team (we just upgraded to .NET 3.5 and I've been assigned the task of getting the team up to speed on some of the new features available to us), and I wrote what I thought was the VB.NET equivalent of the above code, only to discover that it actually throws a NullReferenceException. The code I wrote was this: ' code in module ' <Extension()> _ Function IsNull(ByVal obj As Object) As Boolean Return obj Is Nothing End Function ' code elsewhere ' Dim exampleObject As Object = Nothing Dim exists As Boolean = Not exampleObject.IsNull() The debugger stops right there, as if I'd called an instance method. Am I doing something wrong (e.g., is there some subtle difference in the way I defined the extension method between C# and VB.NET)? Is it actually not legal to call an extension method on a null instance in VB.NET, though it's legal in C#? (I would have thought this was a .NET thing as opposed to a language-specific thing, but perhaps I was wrong.) Can anybody explain this one to me?

  Read the article

< Previous Page | 200 201 202 203 204 205 206 207 208 209 210 211  | Next Page >