这是我后台SpringMVC控制器接收isform参数的方法,只是简单的打出它的值:
@RequestMapping(method = RequestMethod.POST) @ResponseBody public Map<String, Object> save( @RequestParam(value = "isform", required = false) String isform) { System.out.println("isform value: " + isform); return null; }
前台页面发送一个post提交表单的请求
发现后台没有取到值
后边我想到的第一种方案是在控制器方法参数里加requestbody来接收json参数,改成如下:
@RequestMapping(method = RequestMethod.POST) @ResponseBody public Map<String, Object> save( @RequestParam(value = "isform", required = false) @RequestBody String isform) { System.out.println("isform value: " + isform); return null; }
但是isform的值结果还是为null,
接着我又对比了下以前的项目中,接收post请求的参数,发现一个有趣的现象,
下边是Angular的默认请求头:
$httpProvider.defaults.headers.post: (header defaults for POST requests)
Content-Type: application/json
$httpProvider.defaults.headers.put(header defaults for PUT requests)
Content-Type: application/json
其中Angular的post和put都是application/json,
而jquery的post请求的"Content-Type"默认为" application/x-www-form-urlencoded",于是我更改了angular的默认Content-Type,
app.config(function($httpProvider) { $httpProvider.defaults.headers.put['Content-Type'] = 'application/x-www-form-urlencoded'; $httpProvider.defaults.headers.post['Content-Type'] = 'application/x-www-form-urlencoded'; });
接下来的请求body变成了这样,但是后边还是没有取到isform的值,
又查了半天,在一个老外的博客上发现了原因:
By default, jQuery transmits data using Content-Type: x-www-form-urlencoded and the familiar foo=bar&baz=moe serialization. AngularJS, however, transmits data using Content-Type: application/json and { "foo": "bar", "baz": "moe" } JSON serialization
自己翻译了:
默认情况下,jQuery传输数据使用Content-Type: x-www-form-urlencodedand和类似于"foo=bar&baz=moe"的序列,然而AngularJS,传输数据使用Content-Type: application/json和{ "foo": "bar", "baz": "moe" }这样的json序列。
所以下把Content-Type设置成x-www-form-urlencodedand之后,还需要转换序列的格式,
下边是我经过老外实践而自己测试过的最终方案:
app.config(function($httpProvider) { $httpProvider.defaults.headers.put['Content-Type'] = 'application/x-www-form-urlencoded'; $httpProvider.defaults.headers.post['Content-Type'] = 'application/x-www-form-urlencoded'; // Override $http service's default transformRequest $httpProvider.defaults.transformRequest = [function(data) { /** * The workhorse; converts an object to x-www-form-urlencoded serialization. * @param {Object} obj * @return {String} */ var param = function(obj) { var query = ''; var name, value, fullSubName, subName, subValue, innerObj, i; for (name in obj) { value = obj[name]; if (value instanceof Array) { for (i = 0; i < value.length; ++i) { subValue = value[i]; fullSubName = name + '[' + i + ']'; innerObj = {}; innerObj[fullSubName] = subValue; query += param(innerObj) + '&'; } } else if (value instanceof Object) { for (subName in value) { subValue = value[subName]; fullSubName = name + '[' + subName + ']'; innerObj = {}; innerObj[fullSubName] = subValue; query += param(innerObj) + '&'; } } else if (value !== undefined && value !== null) { query += encodeURIComponent(name) + '=' + encodeURIComponent(value) + '&'; } } return query.length ? query.substr(0, query.length - 1) : query; }; return angular.isObject(data) && String(data) !== '[object File]' ? param(data) : data; }]; });
在angular模块中添加以上代码,我们来看下效果:
发现与jquery的post请求风格一致了,有木有!!!
看下后台的参数接收情况,
isform已经可以正常接收到参数了,大功告成!
以上就是angular的post请求后台接收参数为null的解决方案,希望对大家的学习有所帮助。