Spring boot Thymeleaf：从表单中获取对象

假设我有一个实体：

@Entity
@Table(name = "Building")
@Data
public class Building {

@Id
@Column(name = "buildingId")
@GeneratedValue(strategy = GenerationType.IDENTITY)
private Integer buildingId;

@OneToOne(cascade = {CascadeType.MERGE}
@JoinColumn(name = "buildingType")
private BuildingType buildingType;
 //...

}

在控制器中，我将所有建筑类型放入模型中：

@RequestMapping("/addBuilding")
    public String newBuilding(Model model, @ModelAttribute Building building){
       model.addAttribute("buildingTypes", buildingTypeService.getBuildingTypes()); //gives me an ArrayList<BuildingType>
}

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有可能从Thymeleaf获取对象吗？或者是否有必要为BuildingType创建一个基本的瞬态字段（例如字符串），从Thymeleaf返回，并根据此字段在controller中搜索BuildingType？

从客户端开始，Thymeleaf不存在（客户端，您的控制器）。Thymeleaf是一个模板引擎。现在，Spring（而不是thymeleaf）允许您在控制器中接收对象的方式基于html元素的名称。因此，如果有一个输入名为“x”，另一个输入名为“y”，并且在控制器中映射一个具有x和y属性的对象，则该对象将被填充。另一方面，thymeleaf的“th:field”基本上设置了处理html时输入的名称

<form class="some-form" method="post" th:action="@{/addBuilding}">
    <select id="type" class="some-class" required>
        <option th:each="buildingType : ${buildingTypes}" th:text="${buildingType.name}"></option>
    </select>
    <button type="submit" class="button">Store</butto>
</form>

<form class="some-form" method="post" th:action="@{/addBuilding}" th:object="${building}">
        <select id="type" class="some-class" th:field="*{buildingType}" required>
            <option th:each="buildingType : ${buildingTypes}" th:value="${buildingType}" th:text="${buildingType.name}"></option>
        </select>
        <button type="submit" class="button">Store</button>
</form>

@RequestMapping("/addBuilding")
        public String newBuilding(Model model, @ModelAttribute Building building){
           //...
           System.out.println((building.getBuildingType() instanceof BuildingType)); //false
    }