Summary of whitespace, space and escape characters in C language

1. What are whitespace, space, and escape characters?

(1) Space characters, tabs, newlines, etc. are collectively referred to as whitespace.

(2) Space character, not equivalent to The key on the keyboard does not exist on the keyboard. It is not a space, but it can play the effect of a space and occupy a character position.

(3) Escape character, all ASCII code can be represented by "\" plus a number (usually an octal number).And C defines some letters before adding "\" to indicate common ones that cannot be displayedASCII characters, such as \0,\t,\n, etc., are called escape characters, because the following character is not its original ASCII character meaning.

Two, related extension

①Whitespace is only used in character constants and string constant works. When it appears in other places, it only plays the role of interval. CompileThe program ignores them.Therefore, the use of whitespace in the program does not affect the compiled program, but the use of whitespace in the program appropriate places will increase the clarity and feasibility of the program.readability.

②

Chinese name space character

Input method Use the system's own characterEnter function, enter notepad——Hold Alt + Numpad, enter 127 in turn, and release the Alt key after typing

③All escape characters and their corresponding meanings:

The ones in bold are the ones I use a lot when I do exercises at present

Escape character	Meaning	ASCII value (decimal)
\a	Bell (BEL)	007
\b	Backspace (BS), move the current position to the previous column	008
\f	Form feed (FF), move the current position to the beginning of the next page	012
\n	Line feed (LF), move the current position to the beginning of the next line td>	010
\r	Carriage Return (CR), move the current position to the beginning of the line	013
\t	Horizontal Tabulation (HT) (skip to next TAB position)	009
\v	Vertical Tabulation (VT)	011
\\	represents a backslash character ''\'	092
\'	represents a single quote (apostrophe) character	039
\"	represents a double quote character	034
\?	represents a question mark	063
\0	Null character (NUL)	000
\ddd	Any character represented by 1 to 3 octal digits	Octal with three digits
\xhh	Any character represented in hexadecimal	hex

3. Summary of topic points

1. The difference between space character and blank character

For example: when counting the number of various characters, is it ' ' or '\t', '\n', etc.

Note: Reference: Baidu Encyclopedia