String in C Program

 Strings

A string is simply an array of characters which is terminated by a null character '\0' which shows the end of the string.

Strings are always enclosed by double quotes. Whereas, character is enclosed by single quotes in C.

This declaration and initialization create a string with the word "AKKI".

To hold the \0 (null character) at the end of the array, the size of array is one more than the number of characters in the word "AKKI".

char my_name[5] = {'A', 'K', 'K', 'I','\0'};

we can also write the above statement as follows:

char my_name[] = "AKKI";

C String functions:

To use string functions programmer must import String.h header file.

String.h header file supports all the string functions in C language.

All the string functions are given below.

1 strcat ( ) Concatenates str2 at the end of str1.

2 strncat ( ) appends a portion of string to another

3 strcpy ( ) Copies str2 into str1

4 strncpy ( ) copies given number of characters of one string to another

5 strlen ( ) gives the length of str1.

6 strcmp ( ) Returns 0 if str1 is same as str2. Returns <0 if strl < str2. Returns >0 if str1 > str2.

7 strcmpi ( ) Same as strcmp() function. But, this function negotiates case. ''A'' and ''a'' are treated as same.

8 strchr ( ) Returns pointer to first occurrence of char in str1.

9 strrchr ( ) last occurrence of given character in a string is found

10 strstr ( ) Returns pointer to first occurrence of str2 in str1.

11 strrstr ( ) Returns pointer to last occurrence of str2 in str1.

12 strdup ( ) duplicates the string

13 strlwr ( ) converts string to lowercase

14 strupr ( ) converts string to uppercase

15 strrev ( ) reverses the given string

16 strset ( ) sets all character in a string to given character

17 strnset ( ) It sets the portion of characters in a string to given character

18 strtok ( ) tokenizing given string using delimiter

See Programs section of this app for example of this functions