从现有对象创建新的数组对象

Question

I have a json file that's returned from a service am using. I have no control over the service therefore can't change the structure of the json file. The file looks something like:

menu":[    
 {
  "section":"theMobileMenu",
  "key":"menuItem1Title",
  "content":"Mobile context and principles"
},
{
  "section":"theMobileMenu",
  "key":"menuItem1Link",
  "content":"/mobile/index.html"
},
{
  "section":"theMobileMenu",
  "key":"menuItem2Title",
  "content":"Global guidelines"
},
{
  "section":"theMobileMenu",
  "key":"menuItem2Link",
  "content":"/mobile/global-guidelines.html"
},
{
  "section":"theMobileMenu",
  "key":"menuItem3Title",
  "content":"First impressions"
},
{
  "section":"theMobileMenu",
  "key":"menuItem3Link",
  "content":"/mobile/first-impressions.html"
}
]

I want to create an array of objects like the one below

    "menu":[
 {
 "title":"Mobile context and principles",
 "link":"/mobile/index.html"
 },
{
"title":"Global guidelines",
 "link":"/mobile/global-guidelines.html"
},
{
"title":"First impressions",
 "link":"/mobile/first-impressions.html"
}
]

I've tried something like:

var newData = []
var curData = {};
var x = 1;

$.each(data.menu, function(i, val) {            
    if(val.key == 'menuItem'+x+'Link'){
        curData.link = val.content;         
    }
    if(val.key == 'menuItem'+x+'Title'){
        curData.title = val.content;            
    }
    newData.push(curData)
    curData = []
    x++;            
})  

This doesn't work very well. Any ideas on how to work this out?

Answer 1

Try this:

var data = [{
    "section": "theMobileMenu",
    "key": "menuItem1Title",
    "content": "Mobile context and principles"
}, {
    "section": "theMobileMenu",
    "key": "menuItem1Link",
    "content": "/mobile/index.html"
}, {
    "section": "theMobileMenu",
    "key": "menuItem2Title",
    "content": "Global guidelines"
}, {
    "section": "theMobileMenu",
    "key": "menuItem2Link",
    "content": "/mobile/global-guidelines.html"
}, {
    "section": "theMobileMenu",
    "key": "menuItem3Title",
    "content": "First impressions"
}, {
    "section": "theMobileMenu",
    "key": "menuItem3Link",
    "content": "/mobile/first-impressions.html"
}];

var obj = {};
var menu = data.map(function(v, k) {
    if (v.key.match(/menuItem\d*Title/) !== null) {
        obj = {
            title: v.content
        };
    } else if (v.key.match(/menuItem\d*Link/) !== null) {
        obj.link = v.content;
        return obj;
    }
});
menu = $.grep(menu, function(n) {
    return n == 0 || n
});

The code only works if the keys come in the exact order as shown in the OP.

Answer 2

Try below code using for loop makes easier.. If your data is in the sequence as mentioned above

var data = {
  "menu":
  [    
    {
      "section":"theMobileMenu",
      "key":"menuItem1Title",
      "content":"Mobile context and principles"
    },
    {
      "section":"theMobileMenu",
      "key":"menuItem1Link",
      "content":"/mobile/index.html"
    },
    {
      "section":"theMobileMenu",
      "key":"menuItem2Title",
      "content":"Global guidelines"
    },
    {
      "section":"theMobileMenu",
      "key":"menuItem2Link",
      "content":"/mobile/global-guidelines.html"
    },
    {
      "section":"theMobileMenu",
      "key":"menuItem3Title",
      "content":"First impressions"
    },
    {
      "section":"theMobileMenu",
      "key":"menuItem3Link",
      "content":"/mobile/first-impressions.html"
    }
  ]
};

var newData = [];
var curData = {};
var menu = data.menu;

for(i=0, j=1; i < menu.length; i+=2, j++){
    if(menu[i]['key'] == "menuItem"+j+"Title"){
       curData.title = menu[i]['content'];       
       if($.isPlainObject(menu[i+1]) && menu[i+1]['key'] == "menuItem"+j+"Link"){
         curData.link = menu[i+1]['content'];       
       }
       newData.push(curData);
    }
    curData = {};
} 
console.log(newData);

Output :

[
   {
     "title":"Mobile context and principles",
     "link":"/mobile/index.html"
   },
  {
    "title":"Global guidelines",
    "link":"/mobile/global-guidelines.html"
  },
  {
    "title":"First impressions",
    "link":"/mobile/first-impressions.html"
  }
]

Answer 3

This solution works for any order with a temporary object and some regular expressions for matching key, title and link.

 var object = { menu: [{ "section": "theMobileMenu", "key": "menuItem1Title", "content": "Mobile context and principles" }, { "section": "theMobileMenu", "key": "menuItem1Link", "content": "/mobile/index.html" }, { "section": "theMobileMenu", "key": "menuItem2Title", "content": "Global guidelines" }, { "section": "theMobileMenu", "key": "menuItem2Link", "content": "/mobile/global-guidelines.html" }, { "section": "theMobileMenu", "key": "menuItem3Title", "content": "First impressions" }, { "section": "theMobileMenu", "key": "menuItem3Link", "content": "/mobile/first-impressions.html" }] }, result = function (array) { var temp = {} array.forEach(function (a) { var k = a.key.match(/^menuItem\\d*/); temp[k] = temp[k] || {}; temp[k][a.key.match(/(Title)|(Link)$/)[0].toLowerCase()] = a.content; }); return Object.keys(temp).map(function (k) { return temp[k]; }); }(object.menu); document.write('<pre>' + JSON.stringify(result, 0, 4) + '</pre>'); 

Answer 4

https://jsfiddle.net/VixedS/01x2a8jp/

var oldData = {menu:[{ "section": "theMobileMenus", "key": "menuItem1Title", "content": "Mobile context and principles" }, { "section": "theMobileMenu", "key": "menuItem1Link", "content": "/mobile/index.html" }, { "section": "theMobileMenu", "key": "menuItem2Title", "content": "Global guidelines" }, { "section": "theMobileMenu", "key": "menuItem2Link", "content": "/mobile/global-guidelines.html" }, { "section": "theMobileMenu", "key": "menuItem3Title", "content": "First impressions" }, { "section": "theMobileMenu", "key": "menuItem3Link", "content": "/mobile/first-impressions.html"}]};

var newData = []
$.each(oldData.menu, function(i, val){
    if (this.key.indexOf('Link') > -1)
        newData.push({'title':this.section,'link':this.content});
});

newData=JSON.stringify(newData);