it is possible send message in a specific windows using a Handle Property of  ChatWnd and ChatWnd.SendMessage("message")   command?

Sending messages to a specific chat window works as follows:

code:

---

wndSomeChat.SendMessage("Hi there. ");

---

code:

---

var wndChatWindow;

function someFunctionRunsFirst() {
    wndChatWindow = objChatWnd; // local variable objChatWnd comes from anywhere
}

// ...

function someFunctionRunsLater() {
    // now we decide to send a message to the window we have stored
    if(wndChatWindow) {
        wndChatWindow.SendMessage("Hi there...");
    }
}

---

Thank you.... but now i've got another problem... is it possible to send hidden messages? Because i wanted to sent some program datas without the reciever knowing it.

When you send messages to a recipient, he/she will always see them unless there is a Plus! script running there which implements the OnEvent_ChatWndReceiveMessage function. That function should return an empty string if the message was data to be received and not to be displayed. (But I'm not sure if the opening chat window will be suppressed.)

/edit:
You will find more information about this topic in the Official Scripting Documentation.

thank you i didn't think about that.