[RyDeR`]

pawn Code:

stock randomString(strDest[], strLen = 10)
{
    while(strLen--)
        strDest[strLen] = random(2) ? (random(26) + (random(2) ? 'a' : 'A')) : (random(10) + '0');
}

Example:

pawn Code:

new
    string[10]
;
randomString(string, 10);