C isgraph()

The isgraph() function defined in the ctype.h header file. This function helps to check the specified character is a graphic character or not. The characters are said to be graphic characters they have a graphical representation which means all those characters except whitespace characters that can be printed.


int isgraph(int argument); #where argument will be a character
 

isgraph() Parameters:

The isgraph() function takes a single parameter and is in the form of an integer and the return value should be an integer. When a character is passed it is converted into the integer value corresponding to its ASCII value.

Parameter Description Required / Optional
argument  The character to be checked Required

isgraph() Return Value

 If the given character is a graphic character, isgraph() returns a non-zero integer else zero. When the graphic character is passed we will get a different non-zero integer.

Input Return Value
Zero If the parameter isn't a graphic character
Non zero number If the parameter is a graphic character

Examples of isgraph()

Example 1: How to check the graphic character in C?


#include <stdio.h>
#include <ctype.h>

int main()
{
    char ch;
    int output;

    ch = ' ';
    output = isgraph(ch);
    printf("If %c is passed to isgraph() = %d\n", ch, output);

    ch = '\n';
    output = isgraph(ch);
    printf("If %c is passed to isgraph() = %d\n", ch, output);

    ch = '4';
    output = isgraph(ch);
    printf("If %c is passed to isgraph() = %d\n", ch, output); 
}
 

Output:


If   is passed to isgraph() = 0
If 
If 4 is passed to isgraph() = 1

Example 2: Print all graphic characters using isgraph()


#include <stdio.h>
#include <ctype.h>

int main()
{
    int k;
    printf("All graphic characters are: \n");
    for (k=0;k<=127;++k)
    {
        if (isgraph(k)!=0)
            printf("%c ",k);
    }
    return 0;
}
 

Output:


All graphic characters are: 
! " # $ % & ' ( ) * + , - . / 0 1 2 3 4 5 6 7 8 9 : ; < = > ? @ A B C D E F G H I J K L M N O P Q R S T U V W X Y Z [ \ ] ^ _ ` a b c d e f g h i j k l m n o p q r s t u v w x y z { | } ~