Character Constants
These are four types of character constants:
1. Single Character Constant
2. String character Constant
3. Back slash character constant
4. Enumerated Constant
Single character constant
A character constant is either a single alphabet, a single digit, or a special symbol enclosed with in a pair of single inverted (' ') commas. It also has its ASCII VALUE.
Characters
|
ASCII VALUES
|
A-Z
a-z
0-9
Special Symbols
|
65-90
97-122
48-57
0-47, 58-64, 91-96, 123-127
|
Examples:-
'5' 'xy'
'
'= 0'
'#' '378'
(valid) (invalid)
![698_characters-constants.png](https://www.expertsmind.com/CMSImages/698_characters-constants.png)
Fig: Classification of character constants
String character constant
These are the group of characters enclosed within pair of (" ") quotation. The Last character of string is NULL ('\0').this character acts as a string termination, using this fact we can find out where string ends
Example:-"LALIT MATOLIYA"
"SYSTEM SOFTWARE DEVELOPER"
Escape sequence/backslash character constant
It is used to represent the nonprintable characters (new line, tab, ("\t") mark) etc. "An escape sequence is a 'substitute character' for printing hard to get characters". These are the combination of backslash (\) with 'C' character set.
Back Slash Character
|
Response
|
\a
|
Alert Bell
|
\n
|
New Line
|
\"
|
Quotation mark
|
\b
|
Back Slash
|
\r
|
Carriage return
|
\f
|
From feed
|
\v
|
Vertical tab
|
\o
|
Null
|
\t
|
Horizontal tab
|
\\
|
Back slash
|
There are two characters but they are treated as a single character. It can be stored in character type variable
Enumerated character constant: It is fixed set of values. But only one value is assigned at a time. For Example : enum colour (blue, red, green, purple, white, yellow);
Symbolic Constant
It is the name that use for a sequence of characters. It can be used several times in our program.
Example: #define <name> <value>
Logical Constant
A logical constant can take either of two values true or false. A nonzero value treated as true. A zero value treated as false. Logical constants are very useful in evaluating logical expressions.