变量名称的首字母从大写变为小写 [英] First letter of variable's name is changing from uppercase to lowercase
问题描述
我创建了一个iOS应用，该应用将数据存储到Firebase实时数据库中，如下所示:
I created an iOS app that stores the data to Firebase realtime database like this:
users
- ID
-- Email: "test@domain.com"
-- UsersName: "test"
-- Level: 1
-- XP: 0
现在，我开始使用Kotlin进行Android开发，并且数据以值名称的首字母小写存储，如下所示:
Now I started with Android development using Kotlin and the data is stored with the first letter of the values name lowercased like this:
users
- ID
-- email: "test@domain.com"
-- usersName: "test" (No mistake, the N is uppercased)
-- level: 1
-- xp: 0 (No mistake, the P is lowercase)
这是我的代码:
data class User(var UsersName: String = "",
var XP: Int = 0,
var Level: Int = 1,
var Email: String = "")
private fun saveUserToFirebaseDatabase(){
val uid = FirebaseAuth.getInstance().uid ?: ""
val ref = FirebaseDatabase.getInstance().getReference("users/$uid")
val mDatabase = FirebaseDatabase.getInstance().getReference();
val username = usernameSignUp.text.toString()
val user = User(username, 0, 1, SignUpEmailtext.text.toString())
print(user)
mDatabase.child("users").child(uid).setValue(user)
.addOnSuccessListener {
}
.addOnFailureListener{
}
}
我希望值的名称与在类中的命名方式完全相同(就像iOS应用程序将其保存一样).
I expect the names of the values to be exactly how they are named in the class (like the iOS app saves them).
推荐答案
Kotlin在JVM(Java虚拟机)上运行，因此为了能够运行.kt文件，首先应将其编译为一个Java文件.因此，当使用如下所示的类时:
Kotlin works on JVM (Java Virtual Machine), so in order to be able to run a .kt file, first of all it should be compiled into a Java file. So when using a class that looks like:
data class User(var UsersName: String = "",
var XP: Int = 0,
var Level: Int = 1,
var Email: String = "")
创建相应的Java文件，并根据 Java命名约定重新获得变量:
The corresponding Java file is created and according to the Java Naming Conventions regading variables:
它应该是小写字母，例如
java，lang.
这意味着无论您选择字段名称以大写字母还是小写字母开头，所有字段都将转换为以小写字母开头.这就是为什么数据库中的属性会这样显示.该约定不仅在Java/Kotlin中可用，而且在其他编程语言中也可用，因此我建议您在项目中使用此建议.
This means that doesn't matter if you choose the name of your fields to start either with an uppercase or a lowercase, all fiels are converted to start with a lowercase. That's why the properties in your database are present like that. Not only in Java/Kotlin is this convention available but also in other programming languages, so I recommend you to use this recommendation in your projects.
关于Kotlin，请记住，最后，所有内容都将转换为字节码，以便可以在JVM上运行.
Regarding Kotlin, remember that at the end, everything is converted to byte code so it can work on JVM.
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