spring引导-将数据html传递给控制器

我试图将数据html传递给控制器，但我有一个类似的错误。我的GET方法显然有效，但POST方法无效

java.lang.IllegalStateException: Neither BindingResult nor plain target object for bean name 'post' available as request attribute
    at org.springframework.web.servlet.support.BindStatus.<init>(BindStatus.java:144) ~[spring-webmvc-4.3.4.RELEASE.jar:4.3.4.RELEASE]
    at org.thymeleaf.spring4.util.FieldUtils.getBindStatusFromParsedExpression(FieldUtils.java:401) ~[thymeleaf-spring4-2.1.5.RELEASE.jar:2.1.5.RELEASE]
    at org.thymeleaf.spring4.util.FieldUtils.getBindStatus(FieldUtils.java:328) ~[thymeleaf-spring4-2.1.5.RELEASE.jar:2.1.5.RELEASE]
    at org.thymeleaf.spring4.util.FieldUtils.getBindStatus(FieldUtils.java:294) ~[thymeleaf-spring4-2.1.5.RELEASE.jar:2.1.5.RELEASE]
    at org.thymeleaf.spring4.processor.attr.AbstractSpringFieldAttrProcessor.processAttribute(AbstractSpringFieldAttrProcessor.java:98) ~[thymeleaf-spring4-2.1.5.RELEASE.jar:2.1.5.RELEASE]
    at org.thymeleaf.processor.attr.AbstractAttrProcessor.doProcess(AbstractAttrProcessor.java:87) ~[thymeleaf-2.1.5.RELEASE.jar:2.1.5.RELEASE]
    at org.thymeleaf.processor.AbstractProcessor.process(AbstractProcessor.java:212) ~[thymeleaf-2.1.5.RELEASE.jar:2.1.5.RELEASE]
    at org.thymeleaf.dom.Node.applyNextProcessor(Node.java:1017) ~[thymeleaf-2.1.5.RELEASE.jar:2.1.5.RELEASE]
    at org.thymeleaf.dom.Node.processNode(Node.java:972) ~[thymeleaf-2.1.5.RELEASE.jar:2.1.5.RELEASE]
    at org.thymeleaf.dom.NestableNode.computeNextChild(NestableNode.java:695) ~[thymeleaf-2.1.5.RELEASE.jar:2.1.5.RELEASE]
    at org.thymeleaf.dom.NestableNode.doAdditionalProcess(NestableNode.java:668) ~[thymeleaf-2.1.5.RELEASE.jar:2.1.5.RELEASE]
    at org.thymeleaf.dom.Node.processNode(Node.java:990) ~[thymeleaf-2.1.5.RELEASE.jar:2.1.5.RELEASE]

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我不明白我为什么会出错。

根据您的堆栈跟踪：

java.lang.IllegalStateException:既不是BindingResult也不是plain bean名称“post”的目标对象可用作请求属性

您的问题是：

@有效帖子

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在处理程序方法上。似乎出于某种原因，Spring未能将数据从发布的表单绑定到该对象中。

将@modeldattribute添加到控制器中

public ModelAndView savePost(@Valid @ModelAttribute("post") Post post,@PathVariable("id")Long id)

并检查是否在GET时在模型中添加了Post实例

@RequestMapping(method = RequestMethod.GET)
public String postPage(Model model) {
     model.addAttribute("post", new Post());
     return "login";
}

public ModelAndView savePost(@Valid @ModelAttribute("post") Post post,@PathVariable("id")Long id)

@RequestMapping(method = RequestMethod.GET)
public String postPage(Model model) {
     model.addAttribute("post", new Post());
     return "login";
}