rtti

问题 As it currently stands, this question is not a good fit for our Q&A format. We expect answers to be supported by facts, references, or expertise, but this question will likely solicit debate, arguments, polling, or extended discussion. If you feel that this question can be improved and possibly reopened, visit the help center for guidance. Closed 7 years ago . I am familiar with C++ RTTI, and find the concept interesting. Still there exist a lot of more ways to abuse it than to use it

问题 As it currently stands, this question is not a good fit for our Q&A format. We expect answers to be supported by facts, references, or expertise, but this question will likely solicit debate, arguments, polling, or extended discussion. If you feel that this question can be improved and possibly reopened, visit the help center for guidance. Closed 7 years ago . I am familiar with C++ RTTI, and find the concept interesting. Still there exist a lot of more ways to abuse it than to use it

问题 I saw a few questions about avoiding RTTI, but mine seems to be a bit more specific. Here is an example case: struct Base {}; struct A : Base {}; struct B : Base {}; struct C : Base {}; std::vector<Base*> vec; I want to do something on all possible (unordered) pairs of objects in the vector (if the vector has 3 elements, with 0 and 1, 0 and 2, 1 and 2). The pseudo-code for what I want is something like: if e1 is A and e2 is A: behavior1(e1, e2) elif e1 is A and e2 is B: behavior2(e1, e2) elif

问题 I want use reflection on the current class inside a class procedure/function (static method). How can I do without using the "Self" keyword? And without harcode the class name: this procedure should be override in the descendants. class procedure AAA.SetTableAndSequence; var c : TRttiContext; t : TRttiType; begin c := TRttiContext.Create; try t := c.GetType(Self.ClassType); ... finally c.Free; end; end; 回答1: You can use ClassInfo and GetType: class procedure AAA.SetTableAndSequence; var c:

问题 I read in Android Native Development Kit Cookbook that: By default, Android provides minimal C++ support. There's no Run-time Type Information (RTTI) and C++ exceptions support, and even the C++ standard library support, is partial. The following is a list of the C++ headers supported by Android NDK by default: cassert, cctype,cerrno, cfloat, climits, cmath, csetjmp, csignal, cstddef, cstdint, cstdio, cstdlib, cstring, ctime, cwchar, new, stl_pair.h, typeinfo, utility It is possible to add

问题 I cannot find the answer to this seemingly simple question anywhere. Does the following C++ function use RTTI? It certainly doesn't have to, but I was wondering if there is a guarantee that typeid will be determined at compile time. template <typename T> const char *getName() { return typeid(T).name(); // Resolved at compile time? } 回答1: Since typeid is applied to a type rather than an object, there is no runtime type information, so that overhead won't be a problem. On the other hand: as far

问题 I cannot find the answer to this seemingly simple question anywhere. Does the following C++ function use RTTI? It certainly doesn't have to, but I was wondering if there is a guarantee that typeid will be determined at compile time. template <typename T> const char *getName() { return typeid(T).name(); // Resolved at compile time? } 回答1: Since typeid is applied to a type rather than an object, there is no runtime type information, so that overhead won't be a problem. On the other hand: as far

问题 i have a list of class instances of various kinds. i need to be able to create a new instance of a class without knowing for sure what to create. all the objects involved have the same ancestor. the actual copying of the object's member variables is easy...it's the creation of the new object where i have a problem. admittedly i could do something like this: case MyObjectTypeInstance.MyTypeEnum of obj1: Result:=TObjectType1.Create; obj2: Result:=TObjectType2.Create; obj3: Result:=TObjectType3

问题 For example, is there a way to find out that this class has a virtual constructor (at runtime)? TMyClass = class(TObject) MyStrings: TStrings; constructor Create; virtual; end; For example, in this code I would like to test if the class referenced by Clazz has a virtual constructor: procedure Test; var Clazz: TClass; Instance: TObject; begin Clazz := TMyClass; Instance := Clazz.Create; end; Is there a simple solution, for example using RTTI, which works in Delphi 6 to 2009? 回答1: Looking

问题 For example, is there a way to find out that this class has a virtual constructor (at runtime)? TMyClass = class(TObject) MyStrings: TStrings; constructor Create; virtual; end; For example, in this code I would like to test if the class referenced by Clazz has a virtual constructor: procedure Test; var Clazz: TClass; Instance: TObject; begin Clazz := TMyClass; Instance := Clazz.Create; end; Is there a simple solution, for example using RTTI, which works in Delphi 6 to 2009? 回答1: Looking