string zu int c code example

Example 1: string to int c

atoi(str) is unsafe

This is the prefered method:
(int)strtol(str, (char **)NULL, 10)

Example 2: c string is int

int isNumber(char s[])
{
    for (int i = 0; s[i]!= '\0'; i++)
    {
        if (isdigit(s[i]) == 0)
              return 0;
    }
    return 1;
}