我在 Stackoverflow 上进行了搜索，但没有找到我正在寻找的解决方案
我想在数据库 Firebase 中搜索，如果“名称”等于导航标题中的名称，并且用户用于登录的“电子邮件”等于数据库中的电子邮件，那么它将避免用户添加新项目
Json 看起来像这样
"Items" : {
"-KUMSKLFqMjclbqygnPL" : {
"Item" : "asdfg"
"Name" : "Fadi”,
"User Email" : "<a href="https://stackoverflow.com/cdn-cgi/l/email-protection" class="__cf_email__" data-cfemail="177e577e3974787a" rel="noreferrer noopener nofollow">[email protected]</a>"
}
}
我的代码是
let databaseRef = FIRDatabase.database().reference()
var NAME : String!
var UserEmail : String!
var email : String!
databaseRef.child("Items").queryOrderedByKey().observe(.childAdded, with: { snapshot in
let snapshotValue = snapshot.value as? NSDictionary
NAME = (snapshotValue?["Name"] as? String)!
UserEmail = (snapshotValue?["User Email"] as? String)!
email = (FIRAuth.auth()?.currentUser?.email)!
if NAME == navigationItem.title {
if UserEmail == email {
print ("you can't add new item \(UserEmail)")
}else if UserEmail != email {
print("you can add new Item")
}
}
})
我的问题是如果名称等于 Fadi 但有两个不同的电子邮件 结果将是
you can't add new item Optional("<a href="https://stackoverflow.com/cdn-cgi/l/email-protection" class="__cf_email__" data-cfemail="8fe6cfe6a1ece0e2" rel="noreferrer noopener nofollow">[email protected]</a>")
you can add new Item
它应该只打印
you can't add new item Optional("<a href="https://stackoverflow.com/cdn-cgi/l/email-protection" class="__cf_email__" data-cfemail="acc5ecc582cfc3c1" rel="noreferrer noopener nofollow">[email protected]</a>")
我不知道如何打破它，现在看起来它循环遍历所有数据库
更新:
我尝试德拉威答案
打印结果(snapShot.value):
"-KUMS7J-rCglHrVGX840" = {
"Item" = "asdsd"
"Name" = "a";
"User Email" = "<a href="https://stackoverflow.com/cdn-cgi/l/email-protection" class="__cf_email__" data-cfemail="325372531c515d5f" rel="noreferrer noopener nofollow">[email protected]</a>";
};
结果是对的!但现在我需要从该节点提取用户电子邮件
最佳答案
如果您正在寻找具有特定名称的节点，请尝试以下操作:-
let databaseRef = FIRDatabase.database().reference()
databaseRef.child("Items").queryOrdered(byChild: "Name").queryEqual(toValue: "Fadi").observeSingleEvent(of: .value, with: { (snapShot) in
if let snapDict = snapShot.value as? [String:AnyObject]{
for each in snapDict{
let key = each.key as! String
let name = each.value["Name"] as! String
print(key)
print(name)
}
}
}, withCancel: {(Err) in
print(Err.localizedDescription)
})
关于swift - 如何在数据库 Firebase 中搜索，我们在Stack Overflow上找到一个类似的问题： https://stackoverflow.com/questions/40194937/