Thread: Help with 2-D character array

What you want to do is often called data validation. The two basic ways I know of to handle this is to never accept input in any other form than a string. Then analyze the string to be sure it only contains those things that it should. This will need to be done manually, as there are no prewritten functions to do this for you, given every input is different. Ther are a number of functions that can be used in writing your own validation protocol, however.

Alternatively, you can use member functions of the istream class like fail(), clear(), ignore(), etc. They won't tell you why input failed, bu they can detect some types of failure, like putting in a letter instead of a digit, etc.

To determine how many elements are in an array you can keep track of them as you go along or you can use the sizeof operator to determine the size of the entire array and the size of each element of the array. Then a simple division will give you the number of elements in the array. Most of the string classes have a member function to give you this information, if the array is a string.

Originally Posted by elad

Alternatively, you can use member functions of the istream class like fail(), clear(), ignore(), etc. They won't tell you why input failed, bu they can detect some types of failure, like putting in a letter instead of a digit, etc.

Um...I'm not quite sure how to use this standard functions to do the data validation check, could you raise some example, thx.