isalpha in c

What is isalpha in c programming?

isalpha in c checks the passed character is alphabetic or not.

We can use this function by including ctype.h header file.

This function returns non-zero digit if passed character is alphabet otherwise zero.

Prototype

int isalpha(int a);

Parmeter

This function takes character as input parameter and converts it into ASCII value.

Return value

This function returns non-zero value if passed character is alphabet otherwise zero.

---

Example program for isalpha in c

#include<stdio.h>
#include<ctype.h>
int main()
{
  char x;
  printf("Enter the character \n");
  scanf("%c",&x);
  if(isalpha(x))
    printf("This is an alphabet \n");
  else
    printf("This is not an alphabet \n");
  return 0;
}

Code explanation

isalpha function is called to determine whether the given input value is an alphabet or not. The result is printed on to the console.

isalpha() Man page

---

Difference between isalpha and isalnum in c

isalpha function checks the passed parameter is alphabet or not. isalnum function checks the input parameter is alphanumeric or not.

Prototypes are as follows

int isalpha(int a);

int isalnum(int a);

isalpha in c	isalnum in c
Checks the passed parameter is alphabet or not.	Checks the input parameter is alphanumeric or not.
int isalpha(int a);	int isalnum(int a);

---

People also ask for

---