c  go  java  js  lua  py  vbs  rkt  scm  pro  

A character is a nonnegative integer code that represents a letter, digit, etc.

A character literal is represented by a character delimited by singe quotes. Here are some character literals.

A character string literal is a sequence of one or more characters delimited by double quotes.

In computer memory, the following hold.

• The integer literal 7 has value of 7.
• The character literal '7' has a value of 55.
• The string literal "7" has the value sequence of 55 (character '7') and 0 (string terminator).

These are all different representations in memory and cannot be interchanged in program code without appropriate conversions (e.g., type casts, etc.).

Here is a C program that assigns the character variable ch1 the literal value '7' and then converts that character value to an integer and outputs both. Here is the C code.
#include <stdio.h> int main() { char ch1; int i1; ch1 = '7'; i1 = (int) ch1; printf("ch1=[%c]\n",ch1); printf("i1=[%d]\n",i1); return 0; }
Here is the output of the C code.
ch1=[7] i1=[55]

Here is a program that inputs a character and echoes that character. The character typed by the user is intended to be 'y' for yes or 'n' for no, but this is not checked so any character could be typed. Here is the C code.
#include <stdio.h> int main() { // declarations char ch1; int i1; // input printf("Please answer this question (type y for yes, n for no).\n"); scanf("%c ",&ch1); printf("You typed '%c'.\n",ch1); // process i1 = (int) ch1; // output printf("\n"); printf("Your answer was '%c' [code #%d].\n",ch1,i1); return 0; }
Important: In same cases, a space is needed after the "%c" in the scanf. Otherwise, a null character is input into the character variable. If you do not have the space, your program may work for some inputs but not others.

Here are some examples of input and output for the above program code.

Here is an example input.
y
For the above example input, here is the expected output.
Please answer this question (type y for yes, n for no). You typed 'y'. Your answer was 'y' [code #121].
Here is an example input.
n
For the above example input, here is the expected output.
Please answer this question (type y for yes, n for no). You typed 'n'. Your answer was 'n' [code #110].
Here is an example input.
7
For the above example input, here is the expected output.
Please answer this question (type y for yes, n for no). You typed '7'. Your answer was '7' [code #55].
Note: Checking that user input is valid as called data validation and will be covered later (after code repetition has been covered)

In the character set codes, everyone agrees that the letter "A" (in English) is the integer code 65, the letter "B" is 66, etc.

The control codes, such as control-A is integer code 1, control-B is integer code 2, etc.

A common (beginning) programming error is to use a char where a string is required or a string where a char is required.

13 questions omitted (login required)