从Firebase中检索导致未定义的数据

Question

我试图从Firebase中拉出时出现此问题。我的数据库结构，例如：

我试图拉MERCHANTNAME及其相关分支机构的详细信息：

function getAllMerchant(){ 
    var query = firebase.database().ref('merchants'); 
    return query.once('value').then(data => { 
     var result = []; 
     data.forEach(snapshot => { 
      var merchantData = snapshot.val(); 
      var merchantName = merchantData.merchantName; 
      var branchName = merchantData.branches.branchName; 
      var branchAddress = merchantData.branches.branchAddress; 
      console.log('check ' + merchantName + ' ' + branchName + ' ' + branchAddress); 
      result.push({merchantName: merchantName, branchName: branchName, branchAddress: branchAddress}); 
     }); 
     return result; 
    }); 
    resolve(result); 
} 

然而，当我打印出来的BRANCHNAME和branchAddress，我越来越不确定。尽管我设法打印出merchantName。有任何想法吗？

谢谢！

Answer 1

您并未遍历商户的branches。

data.forEach(merchantSnapshot => { 
    var merchantData = snapshot.val(); 
    var merchantName = merchantData.merchantName; 
    console.log('check ' + merchantName); 
    merchantSnapshot.child("branches").forEach(brancheSnapshot => { 
     var branchName = brancheSnapshot.val().branchName; 
     var branchAddress = brancheSnapshot.val.branchAddress; 
     console.log(' ' + branchName + ' ' + branchAddress); 
    }); 
});