详解Node.js中如何合并两个复杂对象
发布时间：01/15 来源： 浏览：
关键词：
小编推荐的这篇文章详细解析了Node.js中如何合并两个复杂对象的教程，有兴趣的同学可以参考一下
相信大家都知道在通常情况下，在Node.js中我们可以通过underscore的extend或者lodash的merge来合并两个对象，但是对于像下面这种复杂的对象，要如何来应对呢？下面来一起学习学习吧。
Node.js合并两个复杂对象
例如我有以下两个object：
| 代码如下 | |
|
varobj1 = {
"name":"myname",
"status": 0,
"profile": {"sex":"m","isactive":true},
"strarr":["one","three"],
"objarray": [
{
"id": 1,
"email":"a1@me.com",
"isactive":true
},
{
"id": 2,
"email":"a2@me.com",
"isactive":false
}
]
};
varobj2 = {
"name":"myname",
"status": 1,
"newfield": 1,
"profile": {"isactive":false,"city":"new York"},
"strarr":["two"],
"objarray": [
{
"id": 1,
"isactive":false
},
{
"id": 2,
"email":"a2modified@me.com"
},
{
"id": 3,
"email":"a3new@me.com",
"isactive":true
}
]
};
| |
希望合并之后的结果输出成下面这样：
| 代码如下 | |
|
{ name:'myname',
status: 1,
profile: { sex:'m', isactive:false, city:'new York'},
strarr: ['one','three','two'],
objarray:
[ { id: 1, email:'a1@me.com', isactive:false},
{ id: 2, email:'a2modified@me.com', isactive:false},
{ id: 3, email:'a3new@me.com', isactive:true} ],
newfield: 1 }
| |
通过underscore或者lodash现有的方法我们无法实现上述结果，那只能自己写代码来实现了。
| 代码如下 | |
|
functionmergeObjs(def, obj) {
if(!obj) {
returndef;
}elseif(!def) {
returnobj;
}
for(variinobj) {
// if its an object
if(obj[i] !=null&& obj[i].constructor == Object)
{
def[i] = mergeObjs(def[i], obj[i]);
}
// if its an array, simple values need to be joined. Object values need to be remerged.
elseif(obj[i] !=null&& (obj[i]instanceofArray) && obj[i].length > 0)
{
// test to see if the first element is an object or not so we know the type of array we're dealing with.
if(obj[i][0].constructor == Object)
{
varnewobjs = [];
// create an index of all the existing object IDs for quick access. There is no way to know how many items will be in the arrays.
varobjids = {}
for(varx= 0, l= def[i].length ; x < l; x++ )
{
objids[def[i][x].id] = x;
}
// now walk through the objects in the new array
// if the ID exists, then merge the objects.
// if the ID does not exist, push to the end of the def array
for(varx= 0, l= obj[i].length; x < l; x++)
{
varnewobj = obj[i][x];
if(objids[newobj.id] !== undefined)
{
def[i][x] = mergeObjs(def[i][x],newobj);
}
else{
newobjs.push(newobj);
}
}
for(varx= 0, l = newobjs.length; x<l; x++) {
def[i].push(newobjs[x]);
}
}
else{
for(varx=0; x < obj[i].length; x++)
{
varidxObj = obj[i][x];
if(def[i].indexOf(idxObj) === -1) {
def[i].push(idxObj);
}
}
}
}
else
{
def[i] = obj[i];
}
}
returndef;}
| |
将上述代码稍作改进，我们可以实现在合并过程中将Number类型的值自动相加。
| 代码如下 | |
|
functionmerge(def, obj) {
if(!obj) {
returndef;
}
elseif(!def) {
returnobj;
}
for(variinobj) {
// if its an object
if(obj[i] !=null&& obj[i].constructor == Object)
{
def[i] = merge(def[i], obj[i]);
}
// if its an array, simple values need to be joined. Object values need to be re-merged.
elseif(obj[i] !=null&& (obj[i]instanceofArray) && obj[i].length > 0)
{
// test to see if the first element is an object or not so we know the type of array we're dealing with.
if(obj[i][0].constructor == Object)
{
varnewobjs = [];
// create an index of all the existing object IDs for quick access. There is no way to know how many items will be in the arrays.
varobjids = {}
for(varx= 0, l= def[i].length ; x < l; x++ )
{
objids[def[i][x].id] = x;
}
// now walk through the objects in the new array
// if the ID exists, then merge the objects.
// if the ID does not exist, push to the end of the def array
for(varx= 0, l= obj[i].length; x < l; x++)
{
varnewobj = obj[i][x];
if(objids[newobj.id] !== undefined)
{
def[i][x] = merge(def[i][x],newobj);
}
else{
newobjs.push(newobj);
}
}
for(varx= 0, l = newobjs.length; x<l; x++) {
def[i].push(newobjs[x]);
}
}
else{
for(varx=0; x < obj[i].length; x++)
{
varidxObj = obj[i][x];
if(def[i].indexOf(idxObj) === -1) {
def[i].push(idxObj);
}
}
}
}
else
{
if(isNaN(obj[i]) || i.indexOf('_key') > -1){
def[i] = obj[i];
}
else{
def[i] += obj[i];
}
}
}
returndef;
}
| |
例如有以下两个对象：
| 代码如下 | |
|
vardata1 = {
"_id":"577327c544bd90be508b46cc",
"channelId_info": [
{
"channelId_key":"0",
"secondLevel_group": [
{
"secondLevel_key":"568cc36c44bd90625a045c60",
"sender_group": [
{
"sender_key":"577327c544bd90be508b46cd",
"sender_sum": 40.0
}
],
"senders_sum": 40.0
}
],
"channelId_sum": 40.0
}
],
"car_sum": 40.0
};
vardata2 = {
"_id":"577327c544bd90be508b46cc",
"channelId_info": [
{
"channelId_key":"0",
"secondLevel_group": [
{
"secondLevel_key":"568cc36c44bd90625a045c60",
"sender_group": [
{
"sender_key":"577327c544bd90be508b46cd",
"sender_sum": 20.0
},
{
"sender_key":"5710bcc7e66620fd4bc0914f",
"sender_sum": 5.0
}
],
"senders_sum": 25.0
},
{
"secondLevel_key":"55fbeb4744bd9090708b4567",
"sender_group": [
{
"sender_key":"5670f993a2f5dbf12e73b763",
"sender_sum": 10.0
}
],
"senders_sum": 10.0
}
],
"channelId_sum": 35.0
},
{
"channelId_key":"1",
"secondLevel_group": [
{
"secondLevel_key":"568cc36c44bd90625a045c60",
"sender_group": [
{
"sender_key":"577327c544bd90be508b46cd",
"sender_sum": 20.0
}
],
"senders_sum": 20.0
}
],
"channelId_sum": 20.0
}
],
"car_sum": 55.0
};
| |
合并之后的结果如下：
| 代码如下 | |
|
{
"_id":"577327c544bd90be508b46cc",
"channelId_info": [
{
"channelId_key":"0",
"secondLevel_group": [
{
"secondLevel_key":"568cc36c44bd90625a045c60",
"sender_group": [
{
"sender_key":"577327c544bd90be508b46cd",
"sender_sum": 60
},
{
"sender_key":"5710bcc7e66620fd4bc0914f",
"sender_sum": 5
}
],
"senders_sum": 65
},
{
"secondLevel_key":"55fbeb4744bd9090708b4567",
"sender_group": [
{
"sender_key":"5670f993a2f5dbf12e73b763",
"sender_sum": 10
}
],
"senders_sum": 10
}
],
"channelId_sum": 75
},
{
"channelId_key":"1",
"secondLevel_group": [
{
"secondLevel_key":"568cc36c44bd90625a045c60",
"sender_group": [
{
"sender_key":"577327c544bd90be508b46cd",
"sender_sum": 20
}
],
"senders_sum": 20
}
],
"channelId_sum": 20
}
],
"car_sum": 95
}
| |
