for 循环中的 Grails addTo

Question

我正在做一个阅读故事的网站。我的目标是将故事的内容保存到几页中以获得列表，然后轻松地对其进行分页；我做了以下事情:

在域中我创建了两个域，Story:

class Story {

    String title

    List pages

    static hasMany=[users:User,pages:Page]
    static belongsTo = [User]

    static mapping={
        users lazy:false
        pages lazy:false

    }
}

和页面:

class Page {
    String Content
    Story story
    static belongsTo = Story
    static constraints = {
        content(blank:false,size:3..300000)
    }

}

Controller 保存操作是:

def save = {
    def storyInstance = new Story(params)
    def pages = new Page(params)
    String content = pages.content
    String[] contentArr = content.split("\r\n")

    int i=0

    StringBuilder page = new StringBuilder()
    for(StringBuilder line:contentArr){
        i++
        page.append(line+"\r\n")

        if(i%10==0){

               pages.content = page
               storyInstance.addToPages(pages)
               page =new StringBuilder()
        }
    }

    if (storyInstance.save(flush:true)) {
        flash.message = "${message(code: 'default.created.message', args: [message(code: 'story.label', default: 'Story'), storyInstance.id])}"
        redirect(action: "viewstory", id: storyInstance.id)
    }else {
        render(view: "create", model: [storyInstance: storyInstance])
    }
}

(我知道它看起来很乱，但它是一个原型(prototype))

问题是，每次条件为真时，我都在等待 storyInstance.addToPages(pages) 将页面实例添加到页面集中。但实际发生的情况是，它只为我提供了最后一个 page_idx 的实例。我认为它会一页一页地保存页面，这样我就可以获得每个故事的页面列表。

为什么会发生这种情况？有没有比我所做的更简单的方法？

感谢任何帮助。

Answer 1

您仅使用一页...正确的解决方案:

     def save = {
        def storyInstance = new Story(params)
        def i = 0

        StringBuilder page = new StringBuilder()
        for(StringBuilder line in params?.content?.split("\r\n")){
            i++
            page.append(line+"\r\n")

            if(i%10 == 0){
                   storyInstance.addToPages(new Page(content: page.toString()))
                   page = new StringBuilder()
            }
        }

    if (storyInstance.save(flush:true)) {
        flash.message = "${message(code: 'default.created.message', args: [message(code: 'story.label', default: 'Story'), storyInstance.id])}"
        redirect(action: "viewstory", id: storyInstance.id)
    }else {
        render(view: "create", model: [storyInstance: storyInstance])
    }
}