在嵌套的json对象中查找对象

本文介绍了在嵌套的json对象中查找对象的处理方法，对大家解决问题具有一定的参考价值，需要的朋友们下面随着小编来一起学习吧！ 问题描述

我在下面的代码段中嵌套了json对象，并希望查找所有出现的"$ schema"并将包含该架构值的整个对象保存到另一个对象中.我尝试使用lodash过滤器，但未成功.有人有任何建议吗?

I have the nested json object in the snippet below and want to find all occurrences of '$schema' and save the whole object that contains that schema value into another object. I tried using lodash filter but, was unsuccessful. Does anyone have any recommendations.

{ "element": "parseResult", "content": [ { "element": "category", "meta": { "classes": [ "api" ], "title": "Test" }, "attributes": { "meta": [ { "element": "member", "meta": { "classes": [ "user" ] }, "content": { "key": { "element": "string", "content": "FORMAT" }, "value": { "element": "string", "content": "1A" } } } ] }, "content": [ { "element": "category", "meta": { "classes": [ "resourceGroup" ], "title": "Questions" }, "content": [ { "element": "resource", "meta": { "title": "Questions" }, "attributes": { "href": "/questions" }, "content": [ { "element": "transition", "meta": { "title": "List All Questions" }, "content": [ { "element": "httpTransaction", "content": [ { "element": "httpRequest", "attributes": { "method": "GET" }, "content": [] }, { "element": "httpResponse", "attributes": { "statusCode": "200", "headers": { "element": "httpHeaders", "content": [ { "element": "member", "content": { "key": { "element": "string", "content": "Content-Type" }, "value": { "element": "string", "content": "application/json" } } } ] } }, "content": [ { "element": "dataStructure", "content": [ { "element": "Question List" } ] }, { "element": "asset", "meta": { "classes": [ "messageBody" ] }, "attributes": { "contentType": "application/json" }, "content": "[\n {\n \"question\": \"Favourite programming language?\",\n \"published_at\": \"2014-11-11T08:40:51.620Z\",\n \"url\": \"/questions/1\",\n \"choices\": [\n {\n \"choice\": \"Javascript\",\n \"url\": \"/questions/1/choices/1\",\n \"votes\": 2048\n }\n ]\n }\n]" }, { "element": "asset", "meta": { "classes": [ "messageBodySchema" ] }, "attributes": { "contentType": "application/schema+json" }, "content": "{\n \"$schema\": \"json-schema/draft-04/schema#\",\n \"type\": \"array\"\n}" } ] } ] } ] } ] }, { "element": "resource", "meta": { "title": "Question" }, "attributes": { "href": "/questions/{id}", "hrefVariables": { "element": "hrefVariables", "content": [ { "element": "member", "attributes": { "typeAttributes": [ "required" ] }, "content": { "key": { "element": "string", "content": "id" }, "value": { "element": "number", "content": 1234 } } } ] } }, "content": [ { "element": "transition", "meta": { "title": "Retrieve Question" }, "content": [ { "element": "httpTransaction", "content": [ { "element": "httpRequest", "attributes": { "method": "GET" }, "content": [] }, { "element": "httpResponse", "attributes": { "statusCode": "200", "headers": { "element": "httpHeaders", "content": [ { "element": "member", "content": { "key": { "element": "string", "content": "Content-Type" }, "value": { "element": "string", "content": "application/json" } } } ] } }, "content": [ { "element": "dataStructure", "content": [ { "element": "Question" } ] }, { "element": "asset", "meta": { "classes": [ "messageBody" ] }, "attributes": { "contentType": "application/json" }, "content": "{\n \"question\": \"Favourite programming language?\",\n \"published_at\": \"2014-11-11T08:40:51.620Z\",\n \"url\": \"/questions/1\",\n \"choices\": [\n {\n \"choice\": \"Javascript\",\n \"url\": \"/questions/1/choices/1\",\n \"votes\": 2048\n }\n ]\n}" }, { "element": "asset", "meta": { "classes": [ "messageBodySchema" ] }, "attributes": { "contentType": "application/schema+json" }, "content": "{\n \"$schema\": \"json-schema/draft-04/schema#\",\n \"type\": \"object\",\n \"properties\": {\n \"question\": {\n \"type\": \"string\"\n },\n \"published_at\": {\n \"type\": \"string\"\n },\n \"url\": {\n \"type\": \"string\"\n },\n \"choices\": {\n \"type\": \"array\"\n }\n },\n \"required\": [\n \"question\",\n \"published_at\",\n \"url\",\n \"choices\"\n ]\n}" } ] } ] } ] } ] } ] }, { "element": "category", "meta": { "classes": [ "dataStructures" ] }, "content": [ { "element": "dataStructure", "content": [ { "element": "object", "meta": { "id": "Question" }, "content": [ { "element": "member", "attributes": { "typeAttributes": [ "required" ] }, "content": { "key": { "element": "string", "content": "question" }, "value": { "element": "string", "content": "Favourite programming language?" } } }, { "element": "member", "attributes": { "typeAttributes": [ "required" ] }, "content": { "key": { "element": "string", "content": "published_at" }, "value": { "element": "string", "content": "2014-11-11T08:40:51.620Z" } } }, { "element": "member", "attributes": { "typeAttributes": [ "required" ] }, "content": { "key": { "element": "string", "content": "url" }, "value": { "element": "string", "content": "/questions/1" } } }, { "element": "member", "attributes": { "typeAttributes": [ "required" ] }, "content": { "key": { "element": "string", "content": "choices" }, "value": { "element": "array", "content": [ { "element": "Choice" } ] } } } ] } ] }, { "element": "dataStructure", "content": [ { "element": "object", "meta": { "id": "Choice" }, "content": [ { "element": "member", "attributes": { "typeAttributes": [ "required" ] }, "content": { "key": { "element": "string", "content": "choice" }, "value": { "element": "string", "content": "Javascript" } } }, { "element": "member", "attributes": { "typeAttributes": [ "required" ] }, "content": { "key": { "element": "string", "content": "url" }, "value": { "element": "string", "content": "/questions/1/choices/1" } } }, { "element": "member", "attributes": { "typeAttributes": [ "required" ] }, "content": { "key": { "element": "string", "content": "votes" }, "value": { "element": "number", "content": 2048 } } } ] } ] }, { "element": "dataStructure", "content": [ { "element": "array", "meta": { "id": "Question List" }, "content": [ { "element": "Question" } ] } ] } ] } ] } ] }

我尝试过这种方法.

function getObject(theObject) { var result = null; if(theObject instanceof Array) { for(var i = 0; i < theObject.length; i++) { result = getObject(theObject[i]); } } else { for(var prop in theObject) { console.log(prop + ': ' + theObject[prop]); if(prop == '$schema') { if(theObject[prop] == 'json-schema/draft-04/schema#') { return theObject; } } if(theObject[prop] instanceof Object || theObject[prop] instanceof Array) result = getObject(theObject[prop]); } } return result; } var result = getObject(json);

推荐答案

Jacob，

问题出在您的JSON本身中.您的json是键/值对.键可以是字符串(用引号"引起来)以启用具有空格或特殊字符的属性.例如

The problem is in your JSON itself. Your json is a key/value pair. Keys can be strings (surrounded with "quotes") to enable properties that have spaces or special characters. e.g.

var obj = { "my property": "my value" }; var val = obj["my property"] // "my value";

但是，如果您的值是字符串，则它们的值应仅带有引号，否则它将不会被解析为对象-它将保留为字符串表示形式.

However your values should only have quotes around them if they are strings, otherwise it won't get parsed to an object - it will remain in string representation.

var obj = { "foo" : "{ \"bar\" : \"my value\" }" } // notice I had to escape the strings with backslashes \ var val = obj.foo.bar // error because foo is a string with the value "{ "bar" : "my value" }"

在您的json中，content属性的值是一个字符串:

In your json, the value of the content property is a string:

"content": "{\n \"$schema\": \"json-schema/draft-04/schema#\",\n \"type\": \"array\"\n}"

您还需要使用\来对引号进行转义这一事实也告诉您这一点.如果您希望内容在第一时间被解析，那么它应该看起来像这样:

The fact that you needed to escape your quotes with \ tells you this as well. If you expect the content to be parsed the first time, then it should look something like this:

"content": { "$schema": "json-schema/draft-04/schema#", "type": "array" }

如果您无法更改此设置，则可以调用 eval()或 JSON.parse()在内容上将字符串解析为对象(如果您的内容来自用户，这可能是不安全的).

If you can't change this, then you can call an eval() or a JSON.parse() on the content to parse the string to an object (this can be unsafe if your content is coming from the users).

因为您无法更改传入的JSON，所以我创建了一个名为deepParseObject的函数.这绝不是防错的，但我认为它会适合您的情况:

Because you cannot change the JSON coming in, I created a function called deepParseObject. It's by no means error-proof, but I think it will work for your situation:

function deepParseObject(theObject) { for(var prop in theObject) { if(typeof theObject[prop] === "string" && (theObject[prop].indexOf('{') == 0 || theObject[prop].indexOf('[') == 0)) { theObject[prop] = JSON.parse(theObject[prop]); } if(theObject[prop] instanceof Object || theObject[prop] instanceof Array) deepParseObject(theObject[prop]); } }

它的作用是解析内容属性，如果它们的值是字符串，并以{或[开头.之后，您可以调用我的原始getObject函数.这是矮人. plnkr.co/edit/h06wuAxZkxhwCAho3OK6

What it does is parse the content properties if their values are strings and start with a { or [. After that you can call my original getObject function. Here is the plunker. plnkr.co/edit/h06wuAxZkxhwCAho3OK6

我在data.js中调用deepParseObject，而我仅使用AngularJS输出结果...并且因为我喜欢Angular:).

I call deepParseObject in the data.js and I'm only using AngularJS to output the results... and because I like Angular :).