JAVASCRIPT

.trim() method

trim is a method that removeds whitespaces  from both ends of a string and returns a new string, without modifying the original string. Whitespace in this context is all the whitespace characters (space, tab, no-break space, etc.) and all the line terminator characters (LF, CR, etc.)

trim string

const arr = [' a ', ' b ', ' c '];

const results = arr.map(element => {
  return element.trim();
});

console.log(results); 
//result
//['a', 'b', 'c']

//trim single string
var str="		abc c a				"
str.trim()

console.log(str);
//result
//abc c a

trim function

/* Remove leading whitespaces */
char *ltrim(char *const s)
{
        size_t len;
        char *cur;

        if(s && *s) {
                len = strlen(s);
                cur = s;

                while(*cur && isspace(*cur))
                        ++cur, --len;

                if(s != cur)
                        memmove(s, cur, len + 1);

        }

        return s;
}

/* Remove trailing whitespaces */
char *rtrim(char *const s)
{
        size_t len;
        char *cur;

        if(s && *s) {
                len = strlen(s);
                cur = s + len - 1;

                while(cur != s && isspace(*cur))
                        --cur, --len;

                cur[isspace(*cur) ? 0 : 1] = '';
        }

        return s;
}

/* Remove leading and trailing whitespaces */
char *trim(char *const s)
{
        rtrim(s);  // order matters
        ltrim(s);

        return s;
}

A string trim function

String.prototype.trim = function(){return this.replace(/^s+|s+$/g, "");};