标签:请求 接受 value abstract param lstat 结果 成功 外部
第一:传参方式写法,当参数个数大于2个时,需要用@RequestParam
@PostMapping(value = "/configReader/configValue.do",headers = {"Accept=application/json","Content-Type=application/x-www-form-urlencoded"})
//正确的写法
String getMaxCount(@RequestParam("projectName") String projectName, @RequestParam("wordName") String wordName);
//错误的传参方式,会报错
String getMaxCount(String projectName, String wordName);
报错代码为:nested exception is java.lang.IllegalStateException: Method has too many Body parameters: public abstract java.lang.String
第二,@RequestParam 注解的正确用法(很重要!!)
@PostMapping(value = "/configReader/configValue.do",headers = {"Accept=application/json","Content-Type=application/x-www-form-urlencoded"})
//正确的写法
String getMaxCount(@RequestParam("projectName") String projectName, @RequestParam("wordName") String wordName);
好多人没弄明白到底是把“projectName ”里面的参数赋值给projectName,还是把外面的projectname赋值给“projectName”,因为都写一样的,就区分不出来了。
(1)@RequestParam 作为数据发送方 参数配置时,实验如下:
实验一:
数据发送请求方:
@PostMapping(value = "/configReader/configValue.do",headers = {"Accept=application/json","Content-Type=application/x-www-form-urlencoded"})
String getMaxCount(@RequestParam("project") String projectName, @RequestParam("wordName") String wordName);
数据接收方:
String getConfigValue(@RequestParam("projectName") String projectName, @RequestParam("wordName") String wordName)
结果:请求失败,因为
@RequestParam("project") 与@RequestParam("projectName") 不一致
实验二:
数据发送请求方:
@PostMapping(value = "/configReader/configValue.do",headers = {"Accept=application/json","Content-Type=application/x-www-form-urlencoded"})
String getMaxCount(@RequestParam("projectName") String project, @RequestParam("wordName") String wordName);
数据接收方:
String getConfigValue(@RequestParam("projectName") String projectName, @RequestParam("wordName") String wordName)
结果:请求成功
最终结论:@RequestParam("projectName") 是取的别名,String project 是用来接受值的,并将值赋值给别名@RequestParam("projectName") ,然后发送给外部,外部接收数据时,只认别名projectName,一样时才可以接收到数据。
(2)@RequestParam 作为数据接收方,参数配置时,参考
https://www.cnblogs.com/silentdoer/archive/2017/08/31/7459395.html
此时@RequestParam(name="userName", required = false) String[] userNames) username是浏览器请求的参数,userNames 是最终接收的变量
标签:请求 接受 value abstract param lstat 结果 成功 外部
原文地址:https://www.cnblogs.com/Andrew520/p/9432674.html