新手求助，formData传到后台的值取出为null

[qq_41936106]

新人小白，这段时间自己学习慕课网的教程，然后遇见问题，js层ajax通过formData传值给后台，后台通过request.getParameter接收的话，值一直为null

这是js层代码

$("#submit").click(function(){
		var shop = {};
		if(isEdit){
			shop.shopId = shopId;
		}
		shop.shopName = $("#shop-name").val();
		shop.shopAddr = $("#shop-addr").val();
		shop.phone = $("#shop-phone").val();
		shop.shopDesc = $("#shop-desc").val();
		
		shop.shopCategory = {
			shopCategoryId:$("#shop-category").find("option").not(function(){
				return !this.selected;
			}).data("id")
		};
		shop.area = {
			areaId:$("#area").find("option").not(function(){
				return !this.selected;
			}).data("id")	
		};
		var shopImg = $("#shopImg")[0].files[0];
		var formData = new FormData();
		formData.append("shopImg",shopImg);
		formData.append("shopStr",JSON.stringify(shop));
		var verifyCodeActual = $("#j_captcha").val();
		alert("verifyCodeActual:"+verifyCodeActual);
		if(!verifyCodeActual){
			$.toast("请输入验证码！");
			return;
		}
		formData.append("verifyCodeActual",verifyCodeActual);
		$.ajax({
			url:(isEdit?editShopUrl:registerShopUrl),
			tpye:"GET",
			data:{
				"verifyCodeActual":verifyCodeActual
			},
			contentType:false,
			processData:false,
			cache:false,
			success:function(data){
				if(data.success){
					$.toast("提交成功！");
				}else{
					$.toast("提交失败！" + data.errMsg);
				}
				$("#captcha_img").click();
			}
		});
	});

这是Controller层的代码

//修改店铺信息
	@RequestMapping(value="/modifyshop",method=RequestMethod.GET)
	@ResponseBody
	public Map<String ,Object> modifyShop(HttpServletRequest request) {
		Map<String ,Object> modelMap = new HashMap<String ,Object>();
		
		System.out.println("shopImg11:"+request.getParameter("shopImg"));
		
		//验证码验证
		if(!CodeUtil.checkVerifyCode(request)){
			modelMap.put("success", false);
			modelMap.put("errMsg", "验证码输入错误！");
			return modelMap;
		}else{
			modelMap.put("success", true);
		}
		//1.接收并转换相应的参数，包括店铺信息以及图片信息
		String shopStr = HttpServletRequestUtil.getString(request, "shopStr");
		ObjectMapper mapper = new ObjectMapper();
		Shop shop = null;
		try {
			shop = mapper.readValue(shopStr, Shop.class);
		} catch (Exception e) {
			modelMap.put("success", false);
			modelMap.put("errMsg", e.getMessage());
			return modelMap;
		}
		CommonsMultipartFile shopImg = null;
		CommonsMultipartResolver commonsMultipartResolver = 
				new CommonsMultipartResolver(request.getSession().getServletContext());
		if(commonsMultipartResolver.isMultipart(request)){
			MultipartHttpServletRequest multipartHttpServletRequest = (MultipartHttpServletRequest) request;
			shopImg = (CommonsMultipartFile) multipartHttpServletRequest.getFile("shopImg");
		}
		//2.修改店铺信息
		if(shop != null && shop.getShopId() != null){
			PersonInfo owner = (PersonInfo)request.getSession().getAttribute("user");
			shop.setOwner(owner);
			ShopExecution se;
			try {
				if(shopImg == null){
					se = shopService.modifyShop(shop, null, null);
				}else{
					se = shopService.modifyShop(shop, shopImg.getInputStream(),shopImg.getOriginalFilename());
				}
				if(se.getState() == ShopStateEnum.SUCCESS.getState()){
					modelMap.put("success", true);
				}else{
					modelMap.put("success", false);
					modelMap.put("errMsg", se.getStateInfo());
				}
			} catch (Exception e) {
				modelMap.put("success", false);
				modelMap.put("errMsg", e.getMessage());
			}
			return modelMap;
		}else{
			modelMap.put("success", false);
			modelMap.put("errMsg", "请输入店铺ID");
			return modelMap;
		}
	}

这是CodeUtil工具包代码

package com.imooc.o2o.util;

import javax.servlet.http.HttpServletRequest;


public class CodeUtil {
	/**
	 * 后台获取验证码的信息和前台的验证码对比
	 * @param request
	 * @return
	 */
	public static boolean checkVerifyCode(HttpServletRequest request) {
		String verifyCodeExpected = (String) request.getSession().getAttribute(com.google.code.kaptcha.Constants.KAPTCHA_SESSION_KEY);
		String verifyCodeActual = HttpServletRequestUtil.getString(request,"verifyCodeActual");
		System.out.println("verifyCodeActual:"+verifyCodeActual);
		System.out.println("verifyCodeExpected:"+verifyCodeExpected);
		if (verifyCodeActual == null || !verifyCodeActual.equalsIgnoreCase(verifyCodeExpected)) {
			return false;
		}
		return true;
	}
}

这是HttpServletRequestUtil工具包代码

public static String getString(HttpServletRequest request, String name) {
		try {
			String result = request.getParameter(name);
			System.out.println("verifyCodeActual:"+request.getParameter("verifyCodeActual"));
			System.out.println("shopStr:"+request.getParameter("shopStr"));
			System.out.println("shopImg:"+request.getParameter("shopImg"));
			System.out.println("result:"+result);
			if (result != null) {
				result = result.trim();
			}
			if ("".equals(result))
				result = null;
			return result;
		} catch (Exception e) {
			return null;
		}

	}

后台获取的参数一直为空，求各位大神帮帮忙

[竹子_bamboo]

js代码发ajax的时候，写错了

[qq_41936106]

引用 1 楼 sinat_37774909 的回复:

js代码发ajax的时候，写错了

感谢感谢，这段时间敲代码一直手残打错，但是我改正过来了，后台那边接收的参数值还是null

[前方太黑暗]

这个formData 发送到后台了吗

[讨厌走开啦]

post到后台的是verifyCodeActual，而不是formData，检查下传递的数据是否正确。

[evanweng]

。。。你压根就没传

[夜雨恋星辰]

对啊,你ajax传的是
data:{
"verifyCodeActual":verifyCodeActual
}
并没有传formData过去

[丨小莫]

楼上都说完了，我凑个数

[a_b_a_b_a_b_a_b]

见解同6楼，传参到后台不是formData的数据啊

[进击丶Saber]

post请求

[我是一个小小程序员]

这个问题我已经解决了,你可以把它转化为json,然后去点双引号就行,

[smile*_*]

可以把解决的代码发一下吗？谢谢

[jokerls]

就是这种js，各ide都没有对应的报错怎么解决哦

[风吹丶麦浪J]

$.ajax({ url:(isEdit?editShopUrl:registerShopUrl)+"?verifyCodeActual="+verifyCodeActual,（GET请求的参数都需要拼接） tpye:"GET", contentType:false, processData:false, cache:false, success:function(data){ if(data.success){ $.toast("提交成功！"); }else{ $.toast("提交失败！" + data.errMsg); } $("#captcha_img").click(); } });