Stocki

stock IsRPName(name[], minname = 3, bool:firstupperthenlower = true) //By Nickk888
{
    new count, checknumcount, where, tmpname[24], tmpsname[24];
    new len = strlen(name);
    for(new i; i < len; i++) {
        if(name[i] == '_')
            count++,
            where = i;
        switch(name[i]) {
            case 'A'..'Z', 'a'..'z', '_':
                checknumcount++;
        }
    }
    if(count != 1 || (where < minname || len < ((where + 1) + minname)) || checknumcount != len)
        return 0;
    strmid(tmpname, name, 0, where);
    strmid(tmpsname, name, where+1, len);
    checknumcount = 0;
    if(firstupperthenlower) {
        switch(tmpname[0]) {
            case 'A'..'Z':
                checknumcount++;
        }
        for(new i = 1, j = strlen(tmpname); i < j; i++){
            switch(tmpname[i]) {
                case 'a'..'z':
                    checknumcount++;
            }
        }
        switch(tmpsname[0]) {
            case 'A'..'Z':
                checknumcount++;
        }
        for(new i = 1, j = strlen(tmpsname); i < j; i++){
            switch(tmpsname[i]) {
                case 'a'..'z':
                    checknumcount++;
            }
        }
        if((checknumcount + 1) != len)
            return 0;
    }
    return 1;
}

stock IsNumeric(const string[])
{
    for (new i = 0, j = strlen(string); i < j; i++)
    {
        if (string[i] > '9' || string[i] < '0') return 0;
    }
    return 1;
}

forward bool:IsStrValid(string[]);
stock bool:IsStrValid(string[])
{
    new num;
    new len = strlen(string);
    for(new i; i < len; i++)
        switch(string[i])
        {
            case 'A'..'Z':num++;
            case 'a'..'z':num++;
            case '0'..'9':num++;
        }
    if(num == len) return true;
    else return false;
}

stock ClearPlayerChat(playerid)
{
    for(new i; i < 15; i++)
        SendClientMessage(playerid, -1, "");
    return 1;
}

stock PlayerName(playerid)
{
    new gname[MAX_PLAYER_NAME];
    GetPlayerName(playerid, gname, MAX_PLAYER_NAME);
    return gname;
}