angular $http.post request payload方式转为form data

var param = function(obj) {
var query = '', 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;
};

var DnApp = angular.module('DnApp',['ui.router','ngCookies','ngFileUpload','Encryption']);

DnApp.config(
$httpProvider.defaults.headers.post['Content-Type'] = 'application/x-www-form-urlencoded;charset=utf-8';
$httpProvider.defaults.transformRequest = function(data){
return param(data);
})