Character analysis and conversion functions
The predefined functions in “ctype.h” library is for analyzing the character input and converting them.
Analysis functions
| S.No | Function | Description |
|---|---|---|
| 1 | isalpha() | An alphabet or not |
| 2 | isdigit() | A digit or not |
| 3 | isspace() | A space, a new line or tab |
| 4 | ispunct() | A special symbol or not |
| 5 | slower() | A lower case letter of alphabet |
| 6 | isupper() | An upper case letter of alphabet |
| 7 | isalphanumeric() | An alphabet/digit or not |
Converting functions
| Function | Description |
|---|---|
| tolower() | Converts an upper case alphabet to lower case |
| toupper() | Converts a lower case alphabet to upper case |
Example
Let us see a program to demonstrate character analysis and conversion functions −
#include<stdio.h>
#include<ctype.h>
void main(){
//Initializing compile time character variable//
char variable = 'A';
//Reading User I/P//
//printf("Enter the character : ");
//scanf("%c",variable);
//Using character analysis function & printing O/p//
if (isalpha(variable)){
printf("The character entered is :%c, an alphabet",variable);
} else {
printf("The character entered is not an alphabet");
}
}Output
The character entered is :A, an alphabet