[unnyquee]

In case you might refer to what Brreaker said..

PHP Code:

#include <amxmodx>
#include <amxmisc>
#include <cstrike>

#define ACCESS ADMIN_BAN // your access level
#define isPlayer(%1) (1 <= %1 <= get_maxplayers())

new bool:g_bClientBanned[32];

public plugin_init()
{
      register_plugin("Ban for Joining CT Team", "0.0.1", "benamo6");
      
      register_event("TextMsg", "eJoiningCT", "b", "2=#Cstrike_TitlesTXT_Game_join_ct");
      
      register_concmd("amx_ctban", "_ctBan", ACCESS, "<nickname> <status> - sets whether <nickname> can join the CT team or not");
}

public _ctBan(id, level, cid)
{
      if(!cmd_access(id, level, cid, 3))
      {
            return PLUGIN_HANDLED;
      }
      
      new szNickname[32], szStatus[2];
      new iStatus, iTarget;
      
      read_argv(1, szNickname, 31);
      read_argv(2, szStatus, 1);
      
      iStatus = str_to_num(szStatus);
      
      iTarget = cmd_target(id, szNickname, 8);
      
      if(!iTarget || !isPlayer(iTarget))
      {
            return PLUGIN_HANDLED;
      }
      
      if(iStatus == 1)
      {
            g_bClientBanned[iTarget] = true;
      }
      
      else 
      {
            g_bClientBanned[iTarget] = false;
      }
      
      return PLUGIN_HANDLED;
}

public eJoiningCT(id)
{
      if(g_bClientBanned[id] == true)
      {
            client_print(id, print_chat, "* You have been banned from joining the CT Team.");
            client_print(id, print_chat, "* You have been moved to SPECTATORS.");
      }
      
      _moveToSpec(id);
}

_moveToSpec(id)
{
      cs_set_user_team(id, CS_TEAM_SPECTATOR);
} 


..Hope that will do the trick!

Non-tested!

[benamo6]

fR4gn0tiX! you got it right. I need that.
and unny that would work if player stay in server. Because steamid or any playerinfo isnt saved in some data file, so if he reconnect the bool will be false.