C program to print the ASCII values in a string.

In C programming, we can print the ASCII values of characters in a string by iterating through each character and using the %d format specifier to display its numeric ASCII value.

Syntax

while(str[i] != '\0') {
    printf("ASCII Value of %c = %d
", str[i], str[i]);
    i++;
}

String Declaration and Initialization

A string in C is an array of characters terminated by a null character '\0'.

Declaration:

char stringname[size];

Initialization methods:

• Using character constants:

char string[10] = {'H', 'e', 'l', 'l', 'o', '\0'};

• Using string literals:

char string[10] = "Hello";

Example: Print ASCII Values of String Characters

The following program reads a string and prints the ASCII value of each character −

#include <stdio.h>

int main() {
    char string[100] = "TutorialsPoint";
    int i = 0;
    
    printf("String: %s

", string);
    
    while(string[i] != '\0') {
        printf("ASCII Value of '%c' = %d
", string[i], string[i]);
        i++;
    }
    
    return 0;
}

String: TutorialsPoint

ASCII Value of 'T' = 84
ASCII Value of 'u' = 117
ASCII Value of 't' = 116
ASCII Value of 'o' = 111
ASCII Value of 'r' = 114
ASCII Value of 'i' = 105
ASCII Value of 'a' = 97
ASCII Value of 'l' = 108
ASCII Value of 's' = 115
ASCII Value of 'P' = 80
ASCII Value of 'o' = 111
ASCII Value of 'i' = 105
ASCII Value of 'n' = 110
ASCII Value of 't' = 116

How It Works

• The while loop continues until it encounters the null character '\0'
• Inside the loop, printf displays each character using %c and its ASCII value using %d
• The same variable string[i] produces different outputs based on the format specifier used
• The counter i increments to move to the next character

Conclusion

Printing ASCII values of string characters in C is straightforward using a loop and format specifiers. The key is using %c for character display and %d for ASCII value conversion.