Search Results

Search found 24391 results on 976 pages for 'static methods'.

Page 9/976 | < Previous Page | 5 6 7 8 9 10 11 12 13 14 15 16  | Next Page >

  • C#: An object reference is required for the non-static field, method, or Property

    - by Omin
    I feel bad for asking this when there are so many questions that are related but I was not able to find/understand the answer I am looking for. // 2. Develop a program to convert currency X to currency Y and visa versa. using System; class Problem2 { static void Main (string[] args) { while (true) { Console.WriteLine ("1. Currency Conversion from CAD to Won"); Console.WriteLine ("2. Currency Conversion from Won to Cad"); Console.Write ("Choose from the Following: (1 or 2)? "); int option = int.Parse( Console.ReadLine() ); //double x; if (option == 1) { Console.WriteLine ("Type in the amount you would like to Convert CAD to Won: "); //double y =double.Parse( Console.ReadLine()); //Console.WriteLine( cadToWon( y ) ); Console.WriteLine( cadToWon( double.Parse( Console.ReadLine() ) )); } if (option == 2) { Console.WriteLine ("Type in the amount you would like to Convert Won to CAD: "); Console.WriteLine( wonToCad (double.Parse( Console.ReadLine()))); } } } double cadToWon( double x ) { return x * 1113.26; } double wonToCad( double x) { return x / 1113.26; } } This give me the Error messgae "An object reference is required for the non-static field, method, or property 'Problem2..." I know that I'll be able to run the program if I add static infront of the methods but I'm wondering why I need it (I think it's because Main is static?) and what do I need to change in order to use these methods without adding static to them? Thank you

    Read the article

  • Extension methods on a static object

    - by Max Malygin
    I know (or so I hear) that writing extension methods for a single stand alone .net class (not an implementation of IEnumerable) is potential code smell. However, for the sake of making the life easier I need to attach a method to the ConfigurationManager class in asp.net. It's a static object so this won't work: public static List<string> GetSupportedDomains(this ConfigurationManager manager) { //the manager needs to be static. } So the question is - is it possible to write an extension method for a static class in .net?

    Read the article

  • (static initialization order?!) problems with factory pattern

    - by smerlin
    Why does following code raise an exception (in createObjects call to map::at) alternativly the code (and its output) can be viewed here intererestingly the code works as expected if the commented lines are uncommented with both microsoft and gcc compiler (see here), this even works with initMap as ordinary static variable instead of static getter. The only reason for this i can think of is that the order of initialization of the static registerHelper_ object (factory_helper_)and the std::map object (initMap) are wrong, however i cant see how that could happen, because the map object is constructed on first usage and thats in factory_helper_ constructor, so everything should be alright shouldnt it ? I am even more suprised that those doNothing() lines fix the issue, because that call to doNothing() would happen after the critical section (which currently fails) is passed anyway. EDIT: debugging showed, that without the call to factory_helper_.doNothing(), the constructor of factory_helper_ is never called. #include <iostream> #include <string> #include <map> #define FACTORY_CLASS(classtype) \ extern const char classtype##_name_[] = #classtype; \ class classtype : FactoryBase<classtype,classtype##_name_> namespace detail_ { class registerHelperBase { public: registerHelperBase(){} protected: static std::map<std::string, void * (*)(void)>& getInitMap() { static std::map<std::string, void * (*)(void)>* initMap = 0; if(!initMap) initMap= new std::map<std::string, void * (*)(void)>(); return *initMap; } }; template<class TParent, const char* ClassName> class registerHelper_ : registerHelperBase { static registerHelper_ help_; public: //void doNothing(){} registerHelper_(){ getInitMap()[std::string(ClassName)]=&TParent::factory_init_; } }; template<class TParent, const char* ClassName> registerHelper_<TParent,ClassName> registerHelper_<TParent,ClassName>::help_; } class Factory : detail_::registerHelperBase { private: Factory(); public: static void* createObject(const std::string& objclassname) { return getInitMap().at(objclassname)(); } }; template <class TClass, const char* ClassName> class FactoryBase { private: static detail_::registerHelper_<FactoryBase<TClass,ClassName>,ClassName> factory_helper_; static void* factory_init_(){ return new TClass();} public: friend class detail_::registerHelper_<FactoryBase<TClass,ClassName>,ClassName>; FactoryBase(){ //factory_helper_.doNothing(); } virtual ~FactoryBase(){}; }; template <class TClass, const char* ClassName> detail_::registerHelper_<FactoryBase<TClass,ClassName>,ClassName> FactoryBase<TClass,ClassName>::factory_helper_; FACTORY_CLASS(Test) { public: Test(){} }; int main(int argc, char** argv) { try { Test* test = (Test*) Factory::createObject("Test"); } catch(const std::exception& ex) { std::cerr << "caught std::exception: "<< ex.what() << std::endl; } #ifdef _MSC_VER system("pause"); #endif return 0; }

    Read the article

  • non-static method cannot be referenced from a static context

    - by Mith
    I am modifying the source code here: http://thinkandroid.wordpress.com/2009/12/30/getting-response-body-of-httpresponse/ I get this error: non-static method getContentCharSet(org.apache.http.HttpEntity) cannot be referenced from a static context String charset = getContentCharSet(entity); This error is line 13 on the second box. Any ideas? I have been really struggling with this code :-(

    Read the article

  • Can static methods be called using object/instance in .NET

    Ans is Yes and No   Yes in C++, Java and VB.NET No in C#   This is only compiler restriction in c#. You might see in some websites that we can break this restriction using reflection and delegates, but we can’t, according to my little research J I shall try to explain you…   Following is code sample to break this rule using reflection, it seems that it is possible to call a static method using an object, p1 using System; namespace T {     class Program     {         static void Main()         {             var p1 = new Person() { Name = "Smith" };             typeof(Person).GetMethod("TestStatMethod").Invoke(p1, new object[] { });                     }         class Person         {             public string Name { get; set; }             public static void TestStatMethod()             {                 Console.WriteLine("Hello");             }         }     } } but I do not think so this method is being called using p1 rather Type Name “Person”. I shall try to prove this… look at another example…  Test2 has been inherited from Test1. Let’s see various scenarios… Scenario1 using System; namespace T {     class Program     {         static void Main()         {             Test1 t = new Test1();            typeof(Test2).GetMethod("Method1").Invoke(t,                                  new object[] { });         }     }     class Test1     {         public static void Method1()         {             Console.WriteLine("At test1::Method1");         }     }       class Test2 : Test1     {         public static void Method1()         {             Console.WriteLine("At test1::Method2");         }     } } Output:   At test1::Method2 Scenario2         static void Main()         {             Test2 t = new Test2();            typeof(Test2).GetMethod("Method1").Invoke(t,                                          new object[] { });         }   Output:   At test1::Method2   Scenario3         static void Main()         {             Test1 t = new Test2();            typeof(Test2).GetMethod("Method1").Invoke(t,                             new object[] { });         }   Output: At test1::Method2 In all above scenarios output is same, that means, Reflection also not considering the object what you pass to Invoke method in case of static methods. It is always considering the type which you specify in typeof(). So, what is the use passing instance to “Invoke”. Let see below sample using System; namespace T {     class Program     {         static void Main()         {            typeof(Test2).GetMethod("Method1").                Invoke(null, new object[] { });         }     }       class Test1     {         public static void Method1()         {             Console.WriteLine("At test1::Method1");         }     }     class Test2 : Test1     {         public static void Method1()         {             Console.WriteLine("At test1::Method2");         }     } }   Output is   At test1::Method2   I was able to call Invoke “Method1” of Test2 without any object.  Yes, there no wonder here as Method1 is static. So we may conclude that static methods cannot be called using instances (only in c#) Why Microsoft has restricted it in C#? Ans: Really there Is no use calling static methods using objects because static methods are stateless. but still Java and C++ latest compilers allow calling static methods using instances. Java sample class Test {      public static void main(String str[])      {            Person p = new Person();            System.out.println(p.GetCount());      } }   class Person {   public static int GetCount()   {      return 100;   } }   Output          100 span.fullpost {display:none;}

    Read the article

  • Static file download from browser breaking in varnish but works fine in Apache

    - by Ron
    I would at first like to thank everyone at serverfault for this great website and I also come to this site while searching in google for various server related issues and setups. I also have an issue today and so I am posting here and hope that the seniors would help me out. I had setup a website on a dedicated server a few days ago and I used Varnish 3 as the frontend to Apache2 on a Debian Lenny server as the traffic was a bit high. There are several static file downloads of around 10-20 MB in size in the website. The website looked fine in the last few days after I setup. I was checking from a 5mbps + broadband connection and the file downloads were also completed in seconds and working fine. But today I realized that on a slow internet connection the file downloads were breaking off. When I tried to download the files from the website using a browser then it broke off after a minute or so. It kept on happening again and again and so it had nothing to do with the internet connection. The internet connection was around 512 kbps and so it was not dial up level speed too but decent speed where files should easily download though not that fast. Then I thought of trying out with the apache backend port and used the port number to check out if the problem occurs. But then on adding the apache port in the static file download url, the files got downloaded easily and did not break even once. I tried it several times to make sure that it was not a coincidence but every time I was using the apache port in the file download url then it was downloading fine while it was breaking each time with the normal link which was routed through Varnish I suppose. So, it seems Varnish has somehow resulted in the broken file downloads. Could anyone give any idea as to why it is happening and how to fix the problem. For more clarification, take this example: Apache backend set on port 8008, Varnish frontend set on port 80 Now when I download say http://mywebsite.com/directory/filename.extension Then the download breaks off after a minute or so. I cannot be sure it is due to the time or size though and I am just assuming. May be some other reason too. But when I download using: http://mywebsite.com:8008/directory/filename.extension Then the file download does not break at all and it gets download fine. So, it seems that varnish is somehow creating the file download breaking and not apache. Does anybody have any idea as to why it is happening and how can it be fixed. Any help would be highly appreciated. And my varnish default.vcl is backend apache { set backend.host = "127.0.0.1"; set backend.port = "8008"; } sub vcl_deliver { remove resp.http.X-Varnish; remove resp.http.Via; remove resp.http.Age; remove resp.http.Server; remove resp.http.X-Powered-By; }

    Read the article

  • How does GCC compile applications that reference a static library

    - by technobrat
    I've read that the gcc compiler can perform certain optimization when compiling an application that references a static library, for instance - it will "pull" in only that code from the static library that the application depends upon. This helps keep the size of the application's executable to a minimum if portions of the static library are not being used by the app. 1) Is this true? 2) How does GCC know what code from the static library the application is actually using? Does it only look t the header files that are included (directly and indirectly) in the application and then pull code accordingly? Or does it actually look at what methods from the static library are being called?

    Read the article

  • Using Static methods or none static methods in Dao Class ?

    - by dankyy1
    Hi I generate Dao classes for some DB operations in this manner making methods of Dao class as static or none static is better? Using sample dao class below ,If more than one client got to use the AddSampleItem method in same time?how this may result? public class SampleDao { static DataAcessor dataAcessor public static void AddSampleItem(object[] params) { dataAcessor =new DataAcessor(); //generate query here string query="..." dataAcessor.ExecuteQery(query); dataAcessor.Close(); } public static void UpdateSampleItem(object[] params) { dataAcessor =new DataAcessor(); //generate query here string query="..." dataAcessor.ExecuteQery(query); dataAcessor.Close(); } }

    Read the article

  • Static Class Variables in Dynamic Library and Main Program

    - by Paul
    I am working on a project that has a class 'A' that contains a static stl container class. This class is included in both my main program and a .so file. The class uses the default(implicit, not declared) constructor/destructor. The main program loads the .so file using dlopen() and in its destructor, calls dlclose(). The program crashes after main exits when glibc calls the destructor for the static class member variable. The problem appears to be that when dlclose() is called, the destructor for the static variable is called, then when main exits() glibc also calls the destructor, resulting in a double free. I have 2 questions, namely: 1) In this particular case, why are there not two copies of the static variable(yes i know that sounds somewhat ridiculous, but since both the main program and .so file have a separately compiled 'A', shouldn't they each have one?) 2) Is there any way to resolve this issue without re-writing class 'A' to not contain static member variables?

    Read the article

  • C++/CLI: Compiling static library with /CLR support

    - by user289770
    We have old (working) code that consists of a static library compiled with /CLR, and a C++/CLI DLL that links to the static lib. We are about to add new features to this static lib. Now, I've have heard from numerous sources that CLR static libraries are not supported by Microsoft, and therefore I'm pushing to clean this up and switch to DLL before we start adding new features to this project. However, I haven't been able to find any official information from Microsoft regarding this (say, from MSDN - other than their forums). I will appreciate any resources about this whole "static lib with CLR" issue.

    Read the article

  • Static and overriding in Java

    - by Abhishek Jain
    public class B { static int i =1; public static int multiply(int a,int b) { return i; } public int multiply1(int a,int b) { return i; } public static void main(String args[]) { B b = new A(); System.out.println(b.multiply(5,2)); System.out.println(b.multiply1(5,2)); } } class A extends B { static int i =8; public static int multiply(int a,int b) { return 5*i; } public int multiply1(int a,int b) { return 5*i; } } Output: 1 40 Why is it so? Please explain.

    Read the article

  • Alternative to c++ static virtual methods

    - by Jaime Pardos
    In C++ is not possible to declare a static virtual function, neither cast a non-static function to a C style function pointer. Now, I have a plain ol' C SDK that uses function pointers heavily. I have to fill a structure with several function pointers. I was planning to use an abstract class with a bunch of static pure virtual methods, and redefine them in derived classes and fill the structure with them. It wasn't until then that I realized that static virtual are not allowed in C++. Is there any good alternative? The best I can think of is defining some pure virtual methods GetFuncA(), GetFuncB(),... and some static members FuncA()/FuncB() in each derived class, which would be returned by the GetFuncX(). Then a function in the abstract class would call those functions to get the pointers and fill the structure.

    Read the article

  • Protected and Private methods

    - by cabaret
    I'm reading through Beginning Ruby and I'm stuck at the part about private and protected methods. This is a newbie question, I know. I searched through SO for a bit but I couldn't manage to find a clear and newbie-friendly explanation of the difference between private and protected methods. The book gives two examples, the first one for private methods: class Person def initialize(name) set_name(name) end def name @first_name + ' ' + @last_name end private def set_name(name) first_name, last_name = name.split(/\s+/) set_first_name(first_name) set_last_name(last_name) end def set_first_name(name) @first_name = name end def set_last_name(name) @last_name = name end end In this case, if I try p = Person.new("Fred Bloggs") p.set_last_name("Smith") It will tell me that I can't use the set_last_name method, because it's private. All good till there. However, in the other example, they define an age method as protected and when I do fred = Person.new(34) chris = Person.new(25) puts chris.age_difference_with(fred) puts chris.age It gives an error: :20: protected method 'age' called for #<Person:0x1e5f28 @age=25> (NoMethodError) I honestly fail to see the difference between the private and protected methods, it sounds the same to me. Could someone provide me with a clear explanation so I'll never get confused about this again? I'll provide the code for the second example if necessary.

    Read the article

  • How to solve JavaScript origin problem with an application and static file server

    - by recipriversexclusion
    In a system that I'm building I want to serve Static files (static HTML pages and a lot of images), and Dynamic XML generated by my servlet. The dynamic XML is generated from my database (through Hibernate) and I use Restlets to serve it in response to API calls. I want to create a static file server (e.g. Apache) so that this does not interfere with the dynamic server traffic. Currently both servers need to run on the same machine. I've never done something like this before and this is where I'm stuck: The static HTML pages contain JavaScript that makes API calls to the dynamic server. However, since the two servers operate on different ports, I get stuck with the same origin problem. How can this be solved? As a bonus, if you can point me to any resources that explain how to create such a static/dynamic content serving system, I'll be happy. Thanks!

    Read the article

  • C static variables and intialization

    - by yCalleecharan
    Hi, If I have a global static variable x like in this code #include <stdio.h> #include <stdio.h> static int x; int main(void) { DO SOMETHING WITH x HERE x++; } What will be difference if I opted to initialize x to a value first say as in static int x = 0; before entering "main"? In my first case where I didn't assign a value to x, does the compiler implicitly know that x is to be set to zero as it's a static variable? I heard that we can do this with static variables. Thanks a lot...

    Read the article

  • C++ design with static methods

    - by user231536
    I would like to define as class X with a static method: class X { static string get_type () {return "X";} //other virtual methods } I would like to force classes which inherit from X to redefine the get_type() method and return strings different from "X" (I am happy if they just redefine get_type for now). How do I do this? I know that I cannot have virtual static methods. Edit: The question is not about the type_id, but in general about a static method that should be overriden. For example class X { static int getid() {return 1;} }

    Read the article

  • GetValue on static field inside nested classes.

    - by Sir Gallahad
    Hi... I have the following class declared. I need to retreive the class structure and the static values without instanciate it. public MyClass() { public static string field = "Value"; public nestedClass() { public static string nestedField = "NestedValue"; } } I've successfuly used GetFields and GetNestedType to recover the class structure and GetValue(null) works fine on field, but not on nestedField. Let me sample: var fi = typeof(MyClass).GetField("field", BindingFlags.Public | BindingFlags.Static); var nt = typeof(MyClass).GetNestedType("nestedClass", BindingFlags.Public); var nfi = nt.GetField("nestedField", BindingFlags.Public | BindingFlags.Static); // All the above references are detected correctly var value = fi.GetValue(null); // until here everything works fine. value == "Value" var nestedValue = nfi.GetValue(null); // this one does not work!! Anyone knows why the last line does not work and how to work around? Thanks.

    Read the article

  • Setting static IP on CentOS without system-config-network

    - by Josh
    Background information: I have a problem installing system-config-network. It appears it cannot find an update to sqlite (checks every mirror and comes back empty handed.) I have tried the skipping broken option and package cleanups from yum-utils. Since I cannot get it installed, I decided to set an ip manually from console. A quick Google search comes back empty handed as for an easy how-to guide that works. What do I need to do for a currently configured DHCP ip to change it to a Static IP from console. Thanks, Josh

    Read the article

  • Setting a Static IP Running FreeBSD8 in VirtualBox hosted on Windows 7

    - by gvkv
    I'm using VirtualBox on Windows 7 (host) to run a FreeBSD (guest) based web server. I`ve assigned a static ip of 192.168.80. 1 to the (virtualized) NIC which is run in bridged mode. The problem is that when I ping an external server (such as google.com) I get a No route to host error: dimetro# ping google.com PING google.com (66.249.90.104): 56 data bytes ping: sendto: No route to host ... I can ping the BSD server from both another virtualized machine and my host machine and from the server, I can ping everything on the network. The router ip is 192.168.1.1/16. ADDENDUM: I have the following lines in /etc/rc.conf on the BSD VM to configure networking: defaultrouter="192.168.1.1" ifconfig_em0="inet 192.168.80.1 netmask 255.255.0.0"

    Read the article

  • Relaying requests between third party server and Heroku for static IP

    - by Gady
    I have a rails application hosted on Heroku that I need to integrate with 3rd party payments provider. The payment provider requires that my application will have a static IP for incoming and outgoing HTTPS requests. I want to deploy a proxy on a Linode VPS so it can relay the information as a proxy. Relaying the request to the service provider seems easy, I just use their IP. Can I relay requests coming from the service provider to the heroku application? Can I realy the request using a URL (https://myapp.herokuapp.com) ? What is the recommended proxy server to use?

    Read the article

  • HOw to give static ip to router from window XP LAN

    - by Captain Planet
    I have the USB modem internet connection. I am using ICS sharing in XP to share my internet connection. ON window XP LAN i have set up the LAN IP as 192.168.137.1 255.255.255.0 Now i have joined the cable from that XP LAN to another LAPTOP running vista Now if set the LAN on VISTA to get ip automatically them internet don't work but if manually set the ip to 192.168.137.3 255.255.255.0 gateway 192.168.137.1 Then my internet works But i want to join that LAN cable from XP to rouer so that i can use router to divide internet. But i don't know how i can give static ipto router because i think somehow that LAN on XP is not giving the IP address

    Read the article

  • static routes, cisco ASA, remote locations

    - by Jeff
    192.168.3.1(ASA) - 192.168.2.1(ASA) - ( internet ) - 192.168.1.1(ASA) DomainController, FS, Exchange 192.168.0.1(ASA) - above is a rough idea what my network setup looks like. each internal ip (192.168.x.x) is located behind an ASA. Each location has a different gateway for the internet. They all talk to the 192.168.1.1 network for dns, dhcp, dc, exchange and so on. They can only see the 192.168.1.1, they can not see each other. In my Static Routes on my 192.168.1.1 ASA, should i have them configure as follows? example: 192.168.x.x 255.255.255.0 Locations_Internet_Gateway_IP OR 192.168.x.x 255.255.255.0 Main_Locations_Internet_Gateway_IP not sure which configurtation is correct, thanks in advance for any help!

    Read the article

  • Save static version of a webpage to be available offline

    - by Tal Weiss
    Is there a way to save a webpage as static HTML, available for offline viewing, editing etc.? I want to remove all javascript files. Leave only HTML, CSS and images. For example, if this web page has a Facebook Like button, I want the image of the button to be part of the HTML as a regular image (and not be loaded as some Javascript code runs after I load the page). I'm trying to prepare a webpage for an offline demo. When I use the standard "save as HTML complete" like tools, all the Javascript is saved as well, and when viewed offline, all the dynamic content is blanks. Note- I don't expect the dynamic content to work, of course, with no Javascript. I just want the web page to LOOK as though it was just loaded from the interwebs. Thanks, Tal.

    Read the article

  • What is the standard place for static library files on Unix/Ubuntu

    - by Max
    Hi, I am trying to install a library manually, well actually just put it in a sensible location preferably in my LIB path. I have a lib[...].a file and a bunch of headers pertaining to that static library file. If I look under /usr/lib/ I see only .so files, likewise for /lib/, /lib32/ etc. I figure I could chuck it in there, but is there any place where it can get cozy with other .a files or is that as good place as any? I'm not an library expert, but I'm pretty sure it won't matter functionally, but I'd like to learn conventional best practice. Also, where is the standard place to put the headers? Thanks!

    Read the article

  • Apache ProxyPass ignore static files

    - by virtualeyes
    Having an issue with Apache front server connecting to a Jetty application server. I thought that ProxyPass ! in a location block was supposed to NOT pass on processing to the application server, but for some reason that is not happening in my case, Jetty shows a 404 on the missing statics (js, css, etc.) Here's my Apache (v 2.4, BTW) virtual host block: DocumentRoot /path/to/foo ServerName foo.com ServerAdmin [email protected] RewriteEngine On <Directory /path/to/foo> AllowOverride None Require all granted </Directory> ProxyRequests Off ProxyVia Off ProxyPreserveHost On <Proxy *> AddDefaultCharset off Order deny,allow Allow from all </Proxy> # don't pass through requests for statics (image,js,css, etc.) <Location /static/> ProxyPass ! </Location> <Location /> ProxyPass http://localhost:8081/ ProxyPassReverse http://localhost:8081/ SetEnv proxy-sendchunks 1 </Location>

    Read the article

< Previous Page | 5 6 7 8 9 10 11 12 13 14 15 16  | Next Page >