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I have a function that takes funct_name(char *s);
It displays the string, uses string functions on it.
BUT i need to send a LONG INT to it for display.
- cannot convert parameter 1 from 'long' to 'char *' -
if i simply cast it, it compiles but gets errors when running it :
at this statement on debug --> strcpy((char*)datum,s);
(datum is void *)
any way around this problem ?
i need the opposite
gcvt
did it
Thats, cool
to pass a type long to the function you need to change type long into type char *, that is into a string. atol() converts type char * to type long, but that isn't what you want. I think conio.h has a conversion from long to char *, probably ltof() if their function naming pattern holds. But it will be non-standard, meaning your compiler might not have it.
You can write your own ANSI C++ standard function to do this. It will probably go something like this:
//char array to hold digits one by as they are generated
char temp[30];
//number to convert
long num = 123;
//peel off digits one at a time
int holder;
int i = 0;
while (num >= 0)
{
//get first digit on the left of num
holder = num %10;
//cast holder to char and store int temp
temp[i++] = (char)holder;
//divide num by 10 using integer math to peel of least significant
//digit
num = num/10;
}
//now convert temp to string by adding null terminating char
temp[i] = 0;
//now reverse temp so digits are in correct order
strrev(temp);
//now send temp to your function
Well, that almost works, but strrev() isn't ANSI C++ standard either so you should probably write your own string reversal function to get the whole thing ANSI C++ standard. The reversal function might look something like this;
int i;
char ch;
int length = strlen(temp);
for(i = 0; i < length/2; i++)
{
ch = temp[i];
temp[i] = temp[length - 1 - i];
temp[length - 1 - i] = ch;
}
now with a little tweaking you should be burning premium.
The last time I looked there was a ltoa() function that converts a long int value to a string.
Check out stdlib.h