non-static

问题 I know people have asked about this question before but the scenario's were too specific and I am confused about the fundamentals. I have two basic versions of a C# program, one that works, and one that doesn't. I would love it if someone could please explain why I get the error An object reference is required for the nonstatic field, method, or property in the second program. Works: namespace Experiments { class Test { public string myTest = "Gobbledigook"; public void Print() { Console

问题 Closed . This question needs details or clarity. It is not currently accepting answers. Want to improve this question? Add details and clarify the problem by editing this post. Closed 5 years ago . I have a static variable that I use as a counter and a non-static version of the variable that I use to save the value of the counter at certain events. Here is some code: Header: static int UndoID; int UndoRedoID; void SetUnsavedChanges(); Class: At various parts of the class I try something like

问题 I am writing a class library(API) in C#. The class is non-static and contains several public events. Is it possible to trigger those events from a static method in a separate class? For example... class nonStaticDLLCLASS { public event Event1; public CallStaticMethod() { StaticTestClass.GoStaticMethod(); } } class StaticTestClass { public static GoStaticMethod() { // Here I want to fire Event1 in the nonStaticDLLCLASS // I know the following line is not correct but can I do something like

问题 I have trouble using the std::sort function with my custom comparison function when defined inside a class. class Test { private: vector< vector<int> > mat; bool compare(vector<int>, vector<int>); public: void sortMatrix(); } bool Field::compare( vector<int> a, vector<int> b) { return (a.back() < b.back()); } void Test::sortMatrix() { sort(vec.begin(), vec.end(), compare); } I get the following error message: error: reference to non-static member function must be called sort(vec.begin(), vec

问题 I'm working on a DLL project, I'm writing a class with variables and functions in a header and the definitions in a .cpp file like this: .h: #ifndef RE_MATH_H #define RE_MATH_H #ifdef MATHFUNCSDLL_EXPORTS #define RE_MATH_API __declspec(dllimport) #else #define RE_MATH_API __declspec(dllexport) #endif #define PI 3.14159265358979323846 namespace RE_Math { class RE_MATH_API Point { public: double X; double Y; double Z; float alpha; Point(double x, double y, double z, float a); static void

问题 These are created using Android Studio similar to How to modify dummy content in android master/detail activity?. I changed the static method under dummyContent into below: public void fetchData() { // Add some sample items. for (int i = 1; i <= COUNT; i++) { addItem(createDummyItem(i)); } Authenticator.setDefault(new Authenticator() { @Override protected PasswordAuthentication getPasswordAuthentication() { return new PasswordAuthentication( DummyContent.UNAME, DummyContent.PASSWORD

问题 I'm trying to use this function, but I cannot find any examples. So I tried every possible way that I can think of, and each time I get a different error : cv::Mat salMap; cv::saliency::StaticSaliencySpectralResidual::computeSaliency(img, salMap); this causes in error : 'cv::saliency::Saliency::computeSaliency': illegal call of non-static member function Then I tried to instantiate the class like this : cv::saliency::StaticSaliencySpectralResidual myObj; myObj.computeSaliency(grayImg, salMap)

问题 I having these errors on my website: Strict Standards: Non-static method modJumiHelper::getCodeWritten() should not be called statically in /home/kmxsiksf/www/modules/mod_jumi/mod_jumi.php on line 17 Strict Standards: Non-static method modJumiHelper::getStorageSource() should not be called statically in /home/kmxsiksf/www/modules/mod_jumi/mod_jumi.php on line 18 Here is the mod_jumi.php (line 17 and 18 start respectively with $code_written and $storage_source) defined('_JEXEC') or die(

问题 I am trying to parse out a mm/dd/yyyy formatted date into separate fields, but I get the following error when I try to compile: non-static method next() cannot be referenced from a static context What could be causing the error? import java.util.Scanner; public class Problem39 { public static void main(String [ ] args) { boolean isLeapYear =false; int maxDay=0; String stringDate; System.out.println("Enter the date in mm/dd/yyyy format. "); //user input Scanner keyboard = new Scanner(System.in

问题 Why is the 'self'-call to a non-satic method in this example working? class A{ protected function aNonStaticMethod(){ return __class__; } public function aEcho(){ echo self::aNonStaticMethod(); } } Thanks for explanation. 回答1: Calling non-static method statically Theoretically it should not work, but as this comment says: There was no static keyword in php4 but php4 did allow for static calls. To maintain backwards compatibility this was left in when the static keyword was added in php5. This