swift – Realm.create会用同一个主键更新对象吗？

概述我只是好奇,如果我调用realm.create,它会从领域结果自动更新领域对象吗？ // Assuming a "Book" with a primary key of `1` already exists.try! realm.write {realm.create(Book.self, value: ["id": 1, "price": 9000.0], update: true)/ 我只是好奇,如果我调用realm.create,它会从领域结果自动更新领域对象吗？

// Assuming a "Book" with a primary key of `1` already exists.try! realm.write {realm.create(Book.self,value: ["ID": 1,"price": 9000.0],update:   true)// the book's `Title` property will remain unchanged.}

目前看起来我需要再次从领域读取以获取最新的对象.如果我错了,请纠正我.

谢谢

是的,在调用Realm.create(_：value：update :)时指定update：true将导致更新现有对象.

这是基于您提供的代码的片段,演示了这一点：

class Book: Object {    dynamic var ID = ""    dynamic var Title = ""    dynamic var price = 0.0    overrIDe class func primaryKey() -> String? { return "ID" }}let realm = try! Realm()let book = Book(value: ["1","To Kill a Mockingbird",9.99])try! realm.write {    realm.add(book)}let results = realm.allObjects(ofType: Book.self)try! realm.write {    realm.createObject(ofType: Book.self,populateDWith: ["ID": "1","price": 7.99],update: true)}print(book)print(results)

此代码生成以下输出：

Book {    ID = 1;    Title = To Kill a Mockingbird;    price = 7.99;}Results<Book> (    [0] Book {        ID = 1;        Title = To Kill a Mockingbird;        price = 7.99;    })

如您所见,现有对象的price属性已更新为新值.

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