Question

如果我有以下两个域

class Author {
  static hasMany = [books: Book]
  String name
}

class Book {
  static belongsTo = [author: Author]
  String color
}

如何同时为作者添加多本图书？

如下：

def book1 = new Book(color: "white")
def book2 = new Book(color: "black")
def books = []
books << book1
books << book2

def author = new Author(name: "John Doe").addToBooks(books).save()

Answer 1

addToBooks采用Book实例或可用于创建Book实例的地图。这是相对紧凑的：

def book1 = new Book(color: "white")
def book2 = new Book(color: "black")
def books = []
books << book1
books << book2

def author = new Author(name: "John Doe")
books.each { author.addToBooks(it) }
author.save()

一次添加属于父项的多个子项

1 个答案: