Macro works similar to a function, but it's execution time is faster than function. Also, macro simply substitutes the value without performing calculatons where as function does calculations. The following example describes the difference between macro and function:

Macro:

#define sq(x) x*x

if you call sq(5+5), the result will be 35 becos macro directly substitutes the value. i.e, in this case, 5+5*5+5 = 35.

Function:

int sq(x)

{

       return x*x;

}

if you call sq(5+5) now, the result will be 100, because function calculates the argument value (if it has some calculations) and passes to the operation stack. i.e, in this case sq(5+5) will become sq(10) before passing to return x*x.

Hope this clears. Please let me know, if anybody know more about this

hello friend,

thanks for ur sweet efforts.

but i m sorry to say that i also knows what r the differences between macro and function............

actually i want to know what r the SIMILARITIES between macro and function?

i u know plz plz let me know also.

have a nice day..

bye.

now, how do you declare a macro in vb.net

functions are declared as

public function functionname() as datatype

end function

what about a macro

As Priya says from her straight shoot line, that makes sense.

A MACRO CAN CALL ANOTHER MACRO WITH IN ITS DEFINITION, PRETTY MUCH LIKE IN FUNCTIONS.

#define sq(x) x * x; // finds square of 'x'
#define cu(x) sq(x) * x; // finds cube of 'x'

Here a macro calls another macro, which is strticly possible. The similarity in functions could look like this.

int sq(int x) { return ( x * x ); }
int cu(int x) { return ( sq ( x ) * x ); }

would be a valid equivalent set of statements that could do the same functionality as that of above macros.

Hope tha HELPS!!!

Helo Ranjith....Thanx for explaining the difference b/w a macro and a function.......