可以观察到不能正常工作angular2吗？

Question

sendMsg(msgToSend: string, reciepient: string){
    console.log(msgToSend, reciepient, this.user);
    let newObj = {from: this.user['name'], msg: msgToSend};
    this.sub = this.route.params.subscribe( params => {
        let name = reciepient;
        this.service.getUser(name).then(user => this.reciepient = user);
    })
    if(this.reciepient){
        console.log(this.reciepient['inbox']);
        this.reciepient['inbox'].unshift(newObj);
    } else {
        console.log('Try again!!');
    }

}

I am calling above method through my template

<input #reciepient placeholder="Reciepient"/>
<input #message placeholder="Enter your message"/>
<button (click)="sendMsg(message.value, reciepient.value)">Send message</button>

I have user data with two users, Ram and Sai . I logged as Ram and Sending message to Sai. In recipient box I mentioned Sai and typed some message in message box. When I click on send message, first time the message not getting pushed into sai's inbox as doing in sendMsg() method because it is going to else statement and printing Try again!! . On second+ clicks its getting pushed. In the same way, once push success, now If I mentioned no name in recipient box, for first time click it is taking the previous value that is Sai and pushing message, and second+ clicks it is taking null value and prints console message Try again!! . Please help me

Answer 1

Since Observables are doing asynchronuous work, you have to put any followup code that needs data from the subscription into the callback:

sendMsg(msgToSend: string, reciepient: string){
    console.log(msgToSend, reciepient, this.user);

    let newObj = {from: this.user['name'], msg: msgToSend};

    this.sub = this.route.params.subscribe( params => {
        let name = reciepient;

        this.service.getUser(name).then(user => {
            this.reciepient = user;

            if(this.reciepient){
                console.log(this.reciepient['inbox']);
                this.reciepient['inbox'].unshift(newObj);
            } else {
                console.log('Try again!!');
            }
        });
    });
}