isspace in C Programming

The C isspace function is one of the Standard Library Function available in C programming, which is used to check the given character is a space or not.

In this article we will show you, How to use isspace in C Programming language with example. Before we get into the example, the basic syntax of the isspace in C programming language is as shown below.

C isspace Function syntax

Below function will accept single character as the parameter, and find whether the given character is a space or not.

isspace(char)

isspace in C Programming Example 1

The isspace function is used to find whether the given character is a space character or not.

//Example for isspace in C Programming
#include <stdio.h>
#include <ctype.h>

int main()
{
    char ch = ' ';
    
    if(isspace(ch))
    {
        printf("The Character ch is a Space Character \n");
    }
    else
    {
        printf("The Character ch is Not a Space Character \n");
    }
    return 0;
}

OUTPUT

isspace in C Programming Example 2

This C program allows the user to enter any character, and check whether the character is space or not using the isspace function.

//Example for isspace in C Programming
#include <stdio.h>
#include <ctype.h>

int main()
{
    char ch;
    printf("Please Enter Any Valid Character : \n");
    scanf("%c", &ch);

    if(isspace(ch))
    {
      printf("\n You have entered a Space Character");         
    }
    else
    {
      printf("\n %c is not a Space Character", ch);
      printf("\n I request you to enter Space Character");	
    }
}

OUTPUT

Let me enter the Uppercase letter

ANALYSIS

First we declared a character variable called ch.

char ch;

First statement will ask the user to enter any character. And then we are using the scanf to assign the user entered character to ch variable

printf("Please Enter Any Valid Character : \n");
scanf("%c", &ch);

Next, we used the If Statement to check whether the character is space, or not using isspace function. If the condition is True then the following statement will be printed

printf("\n You have entered a Space Character");

If the above condition is FALSE then the given character is not a space. So, it will print below statements

printf("\n %c is not a Space Character", ch);
printf("\n I request you to enter Space Character");

Without using isspace in C Programming Example

This C program allows the user to enter any character, and check whether the character is space or not using the ASCII table. Here we don’t use the built-in function isspace.

//Example for isspace in C Programming
#include <stdio.h>
#include <ctype.h>

int main()
{
    char ch;
    printf("Please Enter Any Valid Character : \n");
    scanf("%c", &ch);

    if(ch == 32)
    {
      printf("\n You have entered a Space Character");         
    }
    else
    {
      printf("\n %c is not a Space Character", ch);
      printf("\n I request you to enter Space Character");	
    }
}

OUTPUT

Since, 32 is the ASCII value for the space, we replaced the C isspace function with 32. I suggest you to cross check the ASCII table.

Let me try another value