How to know is connection Successes or not?

attach onStatus method to your NetConnection object:


var objNetCon:NetConnection;
var strFMSAdd:String;

strFMSAdd = "rtmp://xxx.xxx.xxx.xxx/yourAppName/yourInstanceName";
objNetCon = new NetConnection();

// here's the part that interest you
// objInfo : Object return by FMS
objNetCon.onStatus = function(objInfo){
if(objInfo.code == "NetConnection.Connect.Success"){
trace("you are now connected")
// your code
} else {
// it's best to look for "NetConnection.Connect.Rejected"
trace("connection error:" + objInfo.code)

// for custom message
//trace("connection error:" + objInfo.application.message)
}
}

// connecting to FMS
// you can pass extra parameters
objNetCon.connect(strFMSAdd);