我正在尝试制作一个将发布 CardRequestResource 的表单:
public class CardRequestResource extends ResourceSupport{
private Long cardRequestId;
private String deliveryMethod;
private String address;
private boolean isHomeDelivery;
private String requestDate;
private String expectedDate;
private String comments;
private Long statusId;
private PersonResource person;
//Getters and Setters
}
在我的 Controller 中,我首先加载 JSP 并向 ModelMap 添加一个空的 CardRequestResource:
@RequestMapping(value = { "", "/approval" }, method = RequestMethod.GET)
public String getApproval(ModelMap map) {
map.put("cardRequestResource", new CardRequestResource());
return "cardoffice/approval";
}
我的 JSP 使用 cardRequestResource 模型属性构建表单:
<form:form id="detailForm" name="detailForm" modelAttribute="cardRequestResource">
<form:input path="statusId" type="hidden" id="statusId" name="statusId" />
<form:textarea path="comments" name="comments" id="commentTextarea" rows="7" cols="81" style="font-style: normal;"/>
</form:form>
Javascript 函数进行 AJAX 调用来填充表单值:
function getCardRequestDetails(cardRequestUrl) {
$.ajax({
type : "GET",
url : cardRequestUrl,
dataType : "json",
success : function(response) {
loadCardRequestDetails(response);
},
error : function(response) {}
});
};
function loadCardRequestDetails(cardRequest) {
$("#statusId").attr("value", cardRequest.statusId);
$("#commentTextarea").val(cardRequest.comments);
}
此时,用户可以更新评论文本区域,并且隐藏的输入可以根据用户在字段中输入的内容有条件地改变。然后,当提交表单时,我调用以下 Javascript 函数:
function postCardRequest(url) {
var serialized = $("#detailForm").serialize();
alert(serialized);
$.ajax({
type: "POST",
url: url,
data: serialized,
contentType: "application/json",
dataType: "json"
});
}
该警报显示字段已正确填充最初由 AJAX/Javascript 或用户加载的数据。但是,当我到达 Controller 中处理帖子的处理程序时,CardRequestResource 不为空,但其中的每个字段都是 NULL!
处理程序代码:
@RequestMapping(value = "/approval/submit", method = RequestMethod.POST)
public @ResponseBody Map<String, Object> postCardRequest(@ModelAttribute(value = "cardRequestResource") CardRequestResource cardRequestResource) {
Map<String, Object> responseMap = new HashMap<String, Object>();
final String success = "success";
Boolean isSuccessful = Boolean.FALSE;
if(cardRequestResource != null){
isSuccessful = Boolean.TRUE;
}
//TODO
System.out.println("Status: " + cardRequestResource.getStatusId() + ", Comments: " + cardRequestResource.getComments());
responseMap.put(success, isSuccessful);
return responseMap;
}
最佳答案
所以我想我找到了罪犯!
这个小家伙就在 POST AJAX 调用中:
contentType: "application/json",
我最初将 JSON 发送到我的 Controller ,然后我了解到 Spring MVC 有那个漂亮的 ModelAttribute 注释,所以我不必担心在 POST 期间与 JSON 之间的转换。不幸的是,我没有想到要删除该 contentType 行,并且人们会认为它会抛出错误或仍然存在的内容......显然不是。只是绑定(bind)中的 NULL 值和数小时无结果的调试...
删除该行后,我开始在 CardRequest 属性中获取数据而不是 NULL!
关于forms - Spring MVC ModelAttribute 字段为 Null 而不是表单输入值,我们在Stack Overflow上找到一个类似的问题: https://stackoverflow.com/questions/18004564/