Firebase:第一个参数包含未定义的属性

Aar*_*red 2 javascript firebase firebase-realtime-database

在我的网页中,我尝试从一个Firebase数据库进行查询,并在另一个Firebase数据库进行更新。

问题是,当我尝试在第二个数据库上进行更新时,出现错误消息,指出该属性未定义。

我放置了几个控制台日志,我确定它们包含一个数字值,所以我不确定为什么Firebase抱怨该属性未定义。

我的HTML页面

<html>
    <head>
    <meta charset="utf-8">
    <title>
    Firebase Test
    </title>
    </head>
    <style>
    .alright
    {
        text-align: left;
        border: 1px solid black;
        border-collapse: collapse;
    }
    </style>
    <body>


<input type="button" value="SHUFFLE" onClick="window.location.reload()">

<table class="alright">
<tr>
<th><h1>Niyant</h1></th>
<th><h1>Varun</h1></th>
</tr>

<!--<tr>
<th><h1 id="niyantscoretag"></h1></th>
<th><h1 id="varunscoretag"></h1></th>
</tr>-->
<tr>
<td><h2 id="ns">0</td>
<td><h2 id="vs">0</td>
</tr>
<tr>
<td><h3 id="nrank">0</td>
<td><h3 id="vrank">0</td>
</tr>
<tr>
<td><img id="imgtag1"/></td>
<td><img id="imgtag2"/></td>
</tr>
<tr>
<td><h2>Winner is</h2></td>
<td><img id="imgtag3"/></td>
</tr>
</table>


    <script src="https://www.gstatic.com/firebasejs/3.9.0/firebase.js"></script>
    <script>

      var config = {
        apiKey: "AIzaSyAXpEHm1uLfRLS-6QCun1iVioquEmpmbAI",
        authDomain: "helloworld-3c2e7.firebaseapp.com",
        databaseURL: "https://helloworld-3c2e7.firebaseio.com",
        projectId: "helloworld-3c2e7",
        storageBucket: "helloworld-3c2e7.appspot.com",
        messagingSenderId: "103101977379"
      };
      firebase.initializeApp(config);

      var otherAppConfig = {

    apiKey: "AIzaSyC3UBiLaBJoW0vfY5xJgtFWV_zdKl9vfWo",
    authDomain: "scoringdev-b5ede.firebaseapp.com",
    databaseURL: "https://scoringdev-b5ede.firebaseio.com",
    projectId: "scoringdev-b5ede",
    storageBucket: "scoringdev-b5ede.appspot.com",
    messagingSenderId: "123331117443"

};

var database1 = firebase.initializeApp(config,"primary");
var database1_database = database1.database();

var database2 = firebase.initializeApp(otherAppConfig, "secondary");
var database2_database = database2.database();


/************HERE**********/
var nscoref = database2_database.ref('Niyant/Score');
var vscoref = database2_database.ref('Varun/Score');
var vscore,nscore,vscoreincremented,nscoreincremented;

nscoref.on('value', 
                function(snapshot){


                                        nscore = snapshot.val();
                                        nscoreincremented = nscore + 1;
                                        console.log("nscore = "+nscore);
                                        console.log("nscoreincremented = "+nscoreincremented);

                                   }
        );

vscoref.on('value', 
                function(snapshot){



                                        vscore = snapshot.val();
                                        vscoreincremented = vscore + 1;
                                        console.log("vscore = "+vscore);
                                        console.log("vscoreincremented = "+vscoreincremented);

                                   }
        );




var URLPath1,URLPath2,nsv,vsv;


var num1 = Math.floor(Math.random() * 100) + 1;
var num2 = Math.floor(Math.random() * 100) + 1;

if(num1 < num2)
{
    database2_database.ref('Niyant').set({Score: nscoreincremented});
}
else if(num1 > num2)
{
    database2_database.ref('Varun').set({Score: vscoreincremented});
}


var imgref1 = database1_database.ref(num1+'/Location');
var imgref2 = database1_database.ref(num2+'/Location');
var imgref1_name = database1_database.ref(num1+'/Name');
var imgref2_name = database1_database.ref(num2+'/Name');


imgref1.on('value', 
                function(snapshot){

                                        URLPath1 = snapshot.val();
                                        console.log(URLPath1);
                                        console.log(snapshot.val());

                                        document.getElementById("imgtag1").src = URLPath1;
                                        document.getElementById("nrank").innerText = 'Rank '+num1;
                                        if(num1 < num2)
                                        {
                                            document.getElementById("imgtag3").src = URLPath1;


                                        }

                                   }
        );

imgref2.on('value', 
                function(snapshot){

                                        URLPath2 = snapshot.val();
                                        console.log(URLPath2);


                                         document.getElementById("imgtag2").src = URLPath2;
                                         document.getElementById("vrank").innerText = 'Rank '+num2;
                                         if(num2 < num1)
                                        {
                                            document.getElementById("imgtag3").src = URLPath2;

                                        }
                                  }

        );

imgref1_name.on('value', 
                function(snapshot){

                                        URLPath1_name = snapshot.val();
                                        console.log(URLPath1_name);
                                        console.log(snapshot.val());

                                        document.getElementById("ns").innerText = URLPath1_name;


                                   }
        );

imgref2_name.on('value', 
                function(snapshot){

                                        URLPath2_name = snapshot.val();
                                        console.log(URLPath2_name);


                                         document.getElementById("vs").innerText = URLPath2_name;

                                   }
        );


    </script>



    </body>
    </html>
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这来自Chrome控制台。

在此处输入图片说明

有问题的更新在源中用“ *** HERE ****”注释掉,以供参考。

有人可以帮我吗?

Fra*_*len 5

从Firebase异步读取数据。您的代码无法满足您的要求,这会导致您尝试set在实际加载乐谱之前进行评分。

解决方案是正确同步对数据的访问:首先确保已加载所有内容,然后才更新分数。

var nscoref = database2_database.ref('Niyant/Score');
var vscoref = database2_database.ref('Varun/Score');
var vscore,nscore,vscoreincremented,nscoreincremented;

function updateScore() {
    var num1 = Math.floor(Math.random() * 100) + 1;
    var num2 = Math.floor(Math.random() * 100) + 1;
    if(num1 < num2) {
        database2_database.ref('Niyant').set({Score: nscoreincremented});
    }
    else if(num1 > num2) {
        database2_database.ref('Varun').set({Score: vscoreincremented});
    }
}

nscoref.on('value', function(snapshot){
    nscore = snapshot.val();
    nscoreincremented = nscore + 1;
    if (nscoreincremented && vscoreincremented) {
        updateScore();
    }
});

vscoref.on('value', function(snapshot){
    vscore = snapshot.val();
    vscoreincremented = vscore + 1;
    if (nscoreincremented && vscoreincremented) {
        updateScore();
    }
});
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