7. isprint() :
This function helps us to check whether a specified character is a printable character or not.
Characters like ‘\t’, ‘\n’ etc are not printable character
Rest characters are printable
#include<stdio.h>
#include<conio.h>
#include<ctype.h>
void main()
{
char ch='a'; /* is a printable character */
/* char ch='\t'; */ /* is not a printable character */
clrscr();
if(isprint(ch))
printf("it is a printable character");
else
printf("it is not a printable character");
getch();
}
8. ispunct() :
This function helps us to check whether the specified character is a punctuation character or not.
example:
The function returns nonzero/false if char is any of:
! ” # % & ‘ ( ) ; < = >> ?
[ \ ] * + , – . / : ^ _ { | } ~
#include<stdio.h>
#include<conio.h>
#include<ctype.h>
void main()
{
/* char ch='"'; */ /* is a punctuation character */
char ch='a'; /* is not a punctuation character */
clrscr();
if(ispunct(ch))
printf("it is a punctuation character");
else
printf("it is not a punctuation character");
getch();
}
9. isspace() :
This function helps us to check whether character is a space, tab, carriage return, new line, vertical tab or formfeed or not.
#include<stdio.h>
#include<conio.h>
#include<ctype.h>
void main()
{
//char ch=' '; /* is a space character */
char ch='a'; /* is not a space character */
clrscr();
if(isspace(ch))
printf("it is a space character");
else
printf("it is not a space character");
getch();
}
10. isxdigit() :
This function helps us to check whether the character is a hexadecimal digit (0 to 9, a to f, A to F) or not.
#include<stdio.h>
#include<conio.h>
#include<ctype.h>
void main()
{
char ch;
clrscr();
printf("Enter any character ");
scanf("%c",&ch);
if(isxdigit(ch))
printf("it is a hexadecimal character");
else
printf("it is not a hexadecimal character");
getch();
}
11. tolower() :
This function helps to convert an upper case alphabet to its lower form.
#include<stdio.h>
#include<conio.h>
#include<ctype.h>
void main()
{
char ch;
clrscr();
printf("Enter any character ");
scanf("%c",&ch);
if(isupper(ch))
printf("Lower form is %c",tolower(ch));
else
printf("character is not an upper case alphabet");
getch();
}
12. toupper() :
This function helps us to convert a lower case alphabet to its upper form.
#include<stdio.h>
#include<conio.h>
#include<ctype.h>
void main()
{
char ch;
clrscr();
printf("Enter any character ");
scanf("%c",&ch);
if(islower(ch))
printf("Upper form is %c",toupper(ch));
else
printf("character is not a lower case alphabet");
getch();
}




