C Programming

DATA CONVERSION
The following functions convert between data types.

	atof()		converts an ascii character array to a float
	atoi()		converts an ascii character array to an integer
	itoa()		converts an integer to a character array

Example

	/* convert a string to an integer */
	#include <stdio.h>
	#include <stdlib.h>

	char string[] = "1234";

	main()
	{
		int sum;
		sum = atoi( string );
		printf("Sum = %d\n", sum );
	}

/* convert an integer to a string */
	#include <stdio.h>
	#include <stdlib.h>

	main()
	{
		int sum;
		char buff[20];

		printf("Enter in an integer ");
		scanf(" %d", &sum );
		printf( "As a string it is %s\n", itoa( sum, buff, 10 ) );
	}

Note that itoa() takes three parameters,

the integer to b converted
a character buffer into which the resultant string is stored
a radix value (10=decimal,16=hexadecimal)

In addition, itoa() returns a pointer to the resultant string.