'What is the symbol for whitespace in C?

I am trying to figure out how to check if a character is equal to white-space in C. I know that tabs are '\t' and newlines are '\n', but I want to be able to check for just a regular normal space (from the space-bar) inside of an if statement.

Does anybody know what is the character for this?



Solution 1:[1]

The character representation of a Space is simply ' '.

void foo (const char *s)
{
    unsigned char c;
    ...
    if (c == ' ')
        ...
}

But if you are really looking for all whitespace, then C has a function (actually it's often a macro) for that:

#include <ctype.h>
...

void foo (const char *s)
{
    char c;
    ...
    if (isspace(c))
        ...
}

You can read about isspace here

If you really want to catch all non-printing characters, the function to use is isprint from the same library. This deals with all of the characters below 0x20 (the ASCII code for a space) and above 0x7E (0x7f is the code for DEL, and everything above that is an extension).

In raw code this is equivalent to:

if (c < ' ' || c >= 0x7f)
    // Deal with non-printing characters.

Solution 2:[2]

The ASCII value of Space is 32. So you can compare your char to the octal value of 32 which is 40 or its hexadecimal value which is 20.

if(c == '\40') { ... }

or

if(c == '\x20') { ... }

Any number after the \ is assumed to be octal, if the character just after \ is not x, in which case it is considered to be a hexadecimal.

Solution 3:[3]

No special escape sequence is required: you can just type the space directly:

if (char_i_want_to_test == ' ') { 
    // Do something because it is space
}

In ASCII, space is code 32, so you could specify space by '\x20' or even 32, but you really shouldn't do that.

Aside: the word "whitespace" is a catch all for space, tab, newline, and all of that. When you're referring specifically to the ordinary space character, you shouldn't use the term.

Solution 4:[4]

To check a space symbol you can use the following approach

if ( c == ' ' ) { /*...*/ }

To check a space and/or a tab symbol (standard blank characters) you can use the following approach

#include <ctype.h>

//...

if ( isblank( c ) ) { /*...*/ }

To check a white space you can use the following approach

#include <ctype.h>

//...

if ( isspace( c ) ) { /*...*/ }

Solution 5:[5]

make use of isspace function .

The C library function int isspace(int c) checks whether the passed character is white-space.

sample code:

    int main()
    {

       char var= ' ';

       if( isspace(var) )
       {
          printf("var1 = |%c| is a white-space character\n", var );
       }
/*instead you can easily compare character with ' '  
  */     
    }
Standard white-space characters are ?

' '   (0x20)    space (SPC)
'\t'    (0x09)  horizontal tab (TAB)
'\n'    (0x0a)  newline (LF)
'\v'    (0x0b)  vertical tab (VT)
'\f'    (0x0c)  feed (FF)
'\r'    (0x0d)  carriage return (CR)

source : tutorialpoint

Solution 6:[6]

#include <stdio.h>
main()
{
int c,sp,tb,nl;
sp = 0;
tb = 0;
nl = 0;
while((c = getchar()) != EOF)
{
   switch( c )
{
   case ' ':
        ++sp;
     printf("space:%d\n", sp);
     break;
   case  '\t':
        ++tb;
     printf("tab:%d\n", tb);
     break;
   case '\n':
        ++nl;
     printf("new line:%d\n", nl);
     break;
  }
 }
}

Sources

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Source: Stack Overflow

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Solution 1
Solution 2 Sujit Menon
Solution 3
Solution 4 Vlad from Moscow
Solution 5 Tirupati Rao
Solution 6 stpd_rssn