Grails 数据绑定(bind)多个域类

Question

你好。我有这个类(class):

class Carro {

    String name
    String marca
    String matricula

    static constraints = {
        name(nullable:false, blank:false)
    }

    static mapping = {
        version false
    }
}

class CarroMovel {
    String move
    String rodas
    String espelhos
    Carro carro

    static hasMany = [carros: Carro]

    static constraints = {
        move(nullable:false, blank:false)
    }

    static mapping = {
        version false
    }
}

和 Controller :

class CarroController{
def save2 = {

        def carroInstance = new Carro()
        carroInstance.name = params.name
        carroInstance.marca = params.marca
        carroInstance.matricula = params.matricula

        if (carroInstance.save(flush: true)) {
            redirect(uri:"/home.gsp")
        }
        else {
            render(view: "/testeAdd", model: [carroInstance: carroInstance])
        }

    }

和 View testeAdd.gsp

<g:form controller="carro" action="save2">
<h1>Add New Carro Record</h1>
<p>Basic Information</p>

<label>Name
<span class="small">as</span>
</label>
<input type="text" name="name" value="${carroInstance?.name}" /><br>

<label>Marca
<span class="small">as</span>
</label>
<input type="text" name="marca" value="${carroInstance?.marca}" /><br

  <label>Matricula
<span class="small">as</span>
</label>
<input type="text" name="matricula" value="${carroInstance?.matricula}" /><br>


<g:submitButton name="save" value="Save" id="oneone"/>


<div class="spacer"></div>
  </g:form>

                <g:hasErrors bean="${carroInstance}">
            <div class="errors">
                <g:renderErrors bean="${carroInstance}" as="list" />
            </div>
            </g:hasErrors>

这工作得很好。现在我希望能够对多个域类进行数据绑定(bind)。因此，连同我的 gsp 文件中的当前代码，我还想在同一个 save2 中添加 carroMovel 事件。我不知道该怎么做，特别是因为 Carro 类需要有 carroMovel 类的 id。请问有什么帮助吗？谢谢你。

我遵循了一些建议，现在结果如下(我还不关心错误验证):

 def save3 = {

        def carroInstance = new Carro()
        def carroMovelInstance = new CarroMovel()

        carroInstance.name = params.carro.name
        carroInstance.marca = params.carro.marca
        carroInstance.matricula = params.carro.matricula

        carroMovelInstance.move = params.carroMovel.move
        carroMovelInstance.rodas = params.carroMovel.rodas
        carroMovelInstance.espelhos = params.carroMovel.espelhos

        carroInstance.save()
        carroMovelInstance.carro = carroInstance
        carroMovelInstance.save()

    }

<g:form controller="carro" action="save3">
<h1>Add New Conference Record</h1>
<p>Basic Information</p>

<label>Name
<span class="small">Add your name</span>
</label>
<input type="text" name="carro.name" value="${carroInstance?.name}" /><br>

<label>Marca
<span class="small">Add your name</span>
</label>
<input type="text" name="carro.marca" value="${carroInstance?.marca}" /><br

  <label>Matricula
<span class="small">Add your name</span>
</label>
<input type="text" name="carro.matricula" value="${carroInstance?.matricula}" /><br>

<label>Move
<span class="small">Add your name</span>
</label>
<input type="text" name="carroMovel.move" value="${carroMovelInstance?.move}" /><br>

<label>Rodas
<span class="small">Add your name</span>
</label>
<input type="text" name="carroMovel.rodas" value="${carroMovelInstance?.rodas}" /><br>

<label>Espelho
<span class="small">Add your name</span>
</label>
<input type="text" name="carroMovel.espelho" value="${carroMovelInstance?.espelho}" /><br>

<g:submitButton name="save" value="Save" id="addConference"/>

Carro 对象保存在数据库中，虽然 CarroMovel 没有任何 react ，而且它没有保存，我无法弄清楚。

Answer 1

首先，我会将输入名称更改为 carro.name、carro.marca、carroMovel.move，... 以便按名称区分它们。

<input type="text" name="carro.name"/><br>
<input type="text" name="carro.marca"/><br>
<input type="text" name="carroMovel.move"/><br>

这样做的好处是 Controller 中的绑定(bind)可以通过标准的 Grails 方式完成，并且可以在没有设置 value 属性的情况下在表单中输入正确的值。

carro.properties = params.carro 
carroMovel.properties = params.carroMovel

在 Controller Action 中，您还可以保存和链接 Carro 和 CarroMovel 实例。

carro.save()
carroMovel.carro = carro
carroMovel.save()
if(carroMovel.hasErrors(){
  render(view: 'save3', model: [carro: carro, carroMovel.carroMovel])
}