Thread: need a little help with some Functions.

i am trying to make a program using functions
where i want a input,output,time,and charge all to be functions.
the problem i am having is with putting error checking into the function.
for example say i have this function below
void input (char,int,int)
and i want it to read in 2 times ( the ints) and a char from one of the following, but not output anything until the end of the program.
" choose one of the following "
" a is for apple "
"p is for pineapple"
say the user enters a K, which isnt valid.....how could i use a switch statement for this?
would it be something like this?
case a:
case A: (some statement here?)
break;
case p:
case P: (some statement here?)
break;
default: "Invaild data has been entered"

any ideas? thanks in advance........

I don't quite get your problem. Is it with detecting errors, or is it handling errors. The detecing part can be done with a switch (for example). As for handling you can have your fucntion return an error code. If it returns 0 then all went OK, if it returns 1 then soemthnig went wrong... The other path is to use exceptions. For this you'll need to use the try, throw, catch stuff. Exceptions is a little more complicated, but is way better in the long.

i guess jsut handle them an tell the user that invaild data was entered.
say i used ch for the char i know this much
switch(ch)
case a:
case A: (what should i put here? since i dont want it to output anything in this function)
could this work
"case A: choice = apples"
just assigning it to something? an using the defualt for the error checking?
also with the function that figures the cost would using an if statement like this,
say 1-3are .75, 4-10 are .5, and more than 10 are .25
if (amount <=3)
{cost = .75*amount;
}
else if (amount>=4||amount<=10)
{cost =.50*amount;
}
else if (amount>10)
{cost =.25*amount;
}
an then make a different function to deal with pineapples.? or is there a better way to figure the cost?

I think what he's trying to say is that exceptions are for errors made by the program (runtime bugs) and regular error handling is used for errors from outside sources (ie a person). if not, I am