How do I use structs in C to emulate classes?

Asked by Last Modified  

2 Answers

Learn C Language

Follow 3
Answer

Please enter your answer

D Subba Rao

Follow below example program: typedef struct object object, *setCoordinates; struct object { float x, y; void (*setCoordinates)(object *self, float x, float y); void (*getYCoordinate)(object *self); void (*getXCoordinate)(object *self); }; void object_setCoordinates(object...
read more
Follow below example program: typedef struct object object, *setCoordinates; struct object { float x, y; void (*setCoordinates)(object *self, float x, float y); void (*getYCoordinate)(object *self); void (*getXCoordinate)(object *self); }; void object_setCoordinates(object *self, float x, float y){ self->x = x; self->y = y; } float object_getXCoordinate(object *self){ return self->x; } float object_getYCoordinate(object *self){ return self->y; } object point; point.setCoordinates = object_setCoordinates; point.getYCoordinate = object_getYCoordinate; point.getXCoordinate = object_getXCoordinate; point.setCoordinates(&point, 1, 2); printf("Coordinates: X Coordinate: %f, Y Coordinate: %f", point.getXCoordinate, point.getYCoordinate); read less
Comments
Dislike Bookmark

Tutor

Classes are structures with a hidden pointer to a table of function pointers called VTable. The Vtable itself is static. When types point to Vtables with the same structure but where pointers point to other implementation, you get polymorphism. It is recommended to encapsulate the calls logic in function...
read more
Classes are structures with a hidden pointer to a table of function pointers called VTable. The Vtable itself is static. When types point to Vtables with the same structure but where pointers point to other implementation, you get polymorphism. It is recommended to encapsulate the calls logic in function that take the struct as parameter to avoid code clutter. You should also encapsulate structures instantiation and initialization in functions (this is equivalent to a C++ constructor) and deletion (destructor in C++). These are good practice anyway. typedef struct { int (*SomeFunction)(TheClass* this, int i); void (*OtherFunction)(TheClass* this, char* c); } VTable; typedef struct { VTable* pVTable; int member; } TheClass; To call the function int CallSomeFunction(TheClass* this, int i) { (this->pVTable->SomeFunction)(this, i); } read less
Comments
Dislike Bookmark

Related Questions

What are important topics in C language?
Variables and handling datatypes · Structures · Functions · Pointers · Arrays · Conditional statements and switches · File handling · System
Everest
0 0
5
What is the meaning of \n and \t in C language?
(New line) -- We use it to shift the cursor control to the new line. \t (Horizontal tab) -- We use it to shift the cursor to a couple of spaces to the right in the same line.
Munawar
0 0
5
When is a "switch" statement better than multiple "if" statements?
switch statement is generally best to use when you have more than two conditional expressions based on a single variable of numeric type. For instance, rather than the code if (x == 1) printf(“x...
Shalu
What are the __DATE__ and __TIME__ preprocessor commands?
Preprocessor is first statement that get executed. It tells compiler to pre-process before compilation. _DATE --> The current date as a character literal in "MMM DD YYYY" format. and The current time...
Subhasish
Is it possible to write big safe programs in C++?
yes. C++ is generally used to write system software. For example windows operating system are writeen in C++. Most of the operating system, device driver and antivirus programs are written by using C++.
Sapna
0 0
6

Now ask question in any of the 1000+ Categories, and get Answers from Tutors and Trainers on UrbanPro.com

Ask a Question

Related Lessons

An Interesting discussion about malloc( ) and calloc( )
What are malloc( ) and calloc( )? Simply putting they are the predefined functions in C language. Malloc( ) and calloc( ) are two such functions which are used for more or less identical purpose and...

Shiladitya Munshi

0 0
0
Java and C trainer
Always think any conspect with real-time example like Object -- object must have states and behaviour then only we will call that thing is Object like fan is Object (rotating,color)

Jadav Avinash

0 0
0
Set 0 To Kth Bit In A Variable
The following code snippet Set 0 to Kth Bit in an variable #include int UnsetBitValue(int n, int k);int main(){ printf("%d\n\n",UnsetBitValue(255,6)); return 0;}// Set kth bit to zeroint UnsetBitValue(int...

Umasankar Natarajan

0 0
0
Why Indexing Should Start From Zero In Array ?
Why numbering should start at zero? To denote the subsequence of natural numbers 2, 3, ..., 12 without the pernicious three dots, fourconventions are open to usa) 2 ≤ i < 13b) 1 < i ≤ 12c)...

Sunil Yadav

0 0
0
C Program-Prime Number
/*WAP to print a number entered by the user is prime or not*/ //Header files #include<stdio.h>#include<conio.h> //Main function void main(){ int num,i; //Function for clearing screen clrscr();...

Salim Ahmed Ansari

0 0
0

Recommended Articles

Lasya Infotech: An educational Training...

Lasya Infotech is a Hyderabad based IT training institute founded in 2016 by O Venkat. Believing in his innovation, passion and persistence and with a diverse blend of experience, he started his brainchild to deliver exemplary professional courses to aspiring candidates by honing their skills. Ever since the institute envisions...

Read full article >

Brilliant Academy, a reputed B. Tech Tuition...

Brilliant Academy is one of the reputed institutes for B.Tech tuition classes. This institute is specialised in delivering quality tuition classes for B.E, Engineering - all streams and Engineering diploma courses. Incorporated in 2012, Brillant Academy is a brainchild of Mr Jagadeesh. The main motto of the academy is to...

Read full article >

What is Applications Engineering all about?

Applications engineering is a hot trend in the current IT market.  An applications engineer is responsible for designing and application of technology products relating to various aspects of computing. To accomplish this, he/she has to work collaboratively with the company’s manufacturing, marketing, sales, and customer...

Read full article >

Learn Microsoft Excel

Microsoft Excel is an electronic spreadsheet tool which is commonly used for financial and statistical data processing. It has been developed by Microsoft and forms a major component of the widely used Microsoft Office. From individual users to the top IT companies, Excel is used worldwide. Excel is one of the most important...

Read full article >

Find C Language Classes near you
C Language Classes in Bangalore
C Language Classes in Hyderabad
C Language Classes in Delhi
C Language Classes in Pune
C Language Classes in Chennai
C Language Classes in Mumbai
C Language Classes in Kolkata
C Language Classes in Noida
C Language Classes in Gurgaon
C Language Classes in Ghaziabad

Looking for C Language Classes?

Learn from the Best Tutors on UrbanPro

Are you a Tutor or Training Institute?

Join UrbanPro Today to find students near you