无法将对象数组存储到本地存储(Angular 9)

Question

我正在尝试将一个json对象数组存储到本地存储中，但我不知道为什么它不能工作。我尝试过使用localStorage.setItem('comparisons', JSON.stringify(setComparisons))，但是由于某种原因，没有任何东西被存储。

我知道我存储的数组包含我试图存储的信息，因为在存储之前，当我在控制台中记录该数组时，这些信息都在那里。

我还将类似的对象(不是上述对象的数组)存储在localStorage中，并在检索它们时没有任何问题。我不知道这是不是因为这是一个嵌套了数组的数组，或者什么，但我不能弄清楚。

下面是我的代码：

import { Component, OnDestroy, OnInit, ElementRef } from '@angular/core';

import * as jasmineData from '../../../../assets/data/jasmine.json';
import * as belleData from '../../../../assets/data/belle.json';
import * as trumpData from '../../../../assets/data/trump.json';
import * as katyPerryData from '../../../../assets/data/katyPerry.json';
import * as snoopDogData from '../../../../assets/data/snoopDog.json';

@Component({
  selector: 'ngx-header',
  styleUrls: ['./header.component.scss'],
  templateUrl: './header.component.html',
})


export class HeaderComponent implements OnInit, OnDestroy {
 
 constructor(){}
 
 ngOnInit(){

    if(localStorage.getItem('comparisons')){

      console.log("localStorage 'comparisons', set to: " + JSON.parse(localStorage.getItem('comparisons')))

      let testOutput = JSON.parse(localStorage.getItem('comparisons')) 

      console.log(testOutput) //<<<<< outputs nothing

    }
    else{

      let setComparisons = []

      setComparisons['jasmine'] = jasmineData['default']
      setComparisons['belle'] = belleData['default']
      setComparisons['trump'] = trumpData['default']
      setComparisons['katyPerry'] = katyPerryData['default']
      setComparisons['snoopDog'] = snoopDogData['default']

      console.log(setComparisons) //<<<<<<<<<< this works
 
      localStorage.setItem('comparisons', JSON.stringify(setComparisons)) //<<<<<<<<<<<< this doesn't work

    }
 }

下面是数组中的一个json对象的示例：

trumpData['default'] = 

{
  "word_count": 43336,
  "processed_language": "en",
  "personality": [
    {
      "trait_id": "big5_openness",
      "name": "Openness",
      "category": "personality",
      "percentile": 0.9635579519385504,
      "raw_score": 0.8059142660098279,
      "significant": true,
      "children": [
        {
          "trait_id": "facet_adventurousness",
          "name": "Adventurousness",
          "category": "personality",
          "percentile": 0.6272749945581317,
          "raw_score": 0.5163639722247335,
          "significant": true
        },
        {
          "trait_id": "facet_artistic_interests",
          "name": "Artistic interests",
          "category": "personality",
          "percentile": 0.5549904649909926,
          "raw_score": 0.672324948928981,
          "significant": true
        },
        {
          "trait_id": "facet_emotionality",
          "name": "Emotionality",
          "category": "personality",
          "percentile": 0.28058970637230307,
          "raw_score": 0.6245047073901818,
          "significant": true
        },
        {
          "trait_id": "facet_imagination",
          "name": "Imagination",
          "category": "personality",
          "percentile": 0.19081218603999944,
          "raw_score": 0.6914017394955871,
          "significant": true
        },
        {
          "trait_id": "facet_intellect",
          "name": "Intellect",
          "category": "personality",
          "percentile": 0.9812082240575732,
          "raw_score": 0.7034946040858857,
          "significant": true
        },
        {
          "trait_id": "facet_liberalism",
          "name": "Authority-challenging",
          "category": "personality",
          "percentile": 0.61502043736225,
          "raw_score": 0.5309578314898162,
          "significant": true
        }
      ]
    },
    {
      "trait_id": "big5_conscientiousness",
      "name": "Conscientiousness",
      "category": "personality",
      "percentile": 0.983679161419448,
      "raw_score": 0.727697468159296,
      "significant": true,
      "children": [
        {
          "trait_id": "facet_achievement_striving",
          "name": "Achievement striving",
          "category": "personality",
          "percentile": 0.9037639682132805,
          "raw_score": 0.7574010167811566,
          "significant": true
        },
        {
          "trait_id": "facet_cautiousness",
          "name": "Cautiousness",
          "category": "personality",
          "percentile": 0.9577606864915309,
          "raw_score": 0.6013821376687818,
          "significant": true
        },
        {
          "trait_id": "facet_dutifulness",
          "name": "Dutifulness",
          "category": "personality",
          "percentile": 0.8973055247237618,
          "raw_score": 0.6899127477824422,
          "significant": true
        },
        {
          "trait_id": "facet_orderliness",
          "name": "Orderliness",
          "category": "personality",
          "percentile": 0.6418796567676541,
          "raw_score": 0.5060623294980398,
          "significant": true
        },
        {
          "trait_id": "facet_self_discipline",
          "name": "Self-discipline",
          "category": "personality",
          "percentile": 0.9263490077860836,
          "raw_score": 0.6396844920960025,
          "significant": true
        },
        {
          "trait_id": "facet_self_efficacy",
          "name": "Self-efficacy",
          "category": "personality",
          "percentile": 0.8527803075035358,
          "raw_score": 0.7899712120456678,
          "significant": true
        }
      ]
    },
    {
      "trait_id": "big5_extraversion",
      "name": "Extraversion",
      "category": "personality",
      "percentile": 0.881805735940201,
      "raw_score": 0.6038432240030011,
      "significant": true,
      "children": [
        {
          "trait_id": "facet_activity_level",
          "name": "Activity level",
          "category": "personality",
          "percentile": 0.6792742431580725,
          "raw_score": 0.564207098178294,
          "significant": true
        },
        {
          "trait_id": "facet_assertiveness",
          "name": "Assertiveness",
          "category": "personality",
          "percentile": 0.9590138650026484,
          "raw_score": 0.7310095956169131,
          "significant": true
        },
        {
          "trait_id": "facet_cheerfulness",
          "name": "Cheerfulness",
          "cttegory": "personality",
          "percentile": 0.22893261753027844,
          "raw_score": 0.5932251409353175,
          "significant": true
        },
        {
          "trait_id": "facet_excitement_seeking",
          "name": "Excitement-seeking",
          "category": "personality",
          "percentile": 0.07232250370319887,
          "raw_score": 0.5417548838864124,
          "significant": true
        },
        {
          "trait_id": "facet_friendliness",
          "name": "Outgoing",
          "category": "personality",
          "percentile": 0.6581074192508122,
          "raw_score": 0.5809171726499361,
          "significant": true
        },
        {
          "trait_id": "facet_gregariousness",
          "name": "Gregariousness",
          "category": "personality",
          "percentile": 0.20363538067938197,
          "raw_score": 0.4107392559079223,
          "significant": true
        }
      ]
    },
    {
      "trait_id": "big5_agreeableness",
      "name": "Agreeableness",
      "category": "personality",
      "percentile": 0.636750368115894,
      "raw_score": 0.7561040242628326,
      "significant": true,
      "children": [
        {
          "trait_id": "facet_altruism",
          "name": "Altruism",
          "category": "personality",
          "percentile": 0.8106883789426762,
          "raw_score": 0.7359758754762658,
          "significant": true
        },
        {
          "trait_id": "facet_cooperation",
          "name": "Cooperation",
          "category": "personality",
          "percentile": 0.5694503320384123,
          "raw_score": 0.5899309252875584,
          "significant": true
        },
        {
          "trait_id": "facet_modesty",
          "name": "Modesty",
          "category": "personality",
          "percentile": 0.40713913944183266,
          "raw_score": 0.43598028092279484,
          "significant": true
        },
        {
          "trait_id": "facet_morality",
          "name": "Uncompromising",
          "category": "personality",
          "percentile": 0.8195717940201414,
          "raw_score": 0.6689246296236344,
          "significant": true
        },
        {
          "trait_id": "facet_sympathy",
          "name": "Sympathy",
          "category": "personality",
          "percentile": 0.9920577260424773,
          "raw_score": 0.755562118052558,
          "significant": true
        },
        {
          "trait_id": "facet_trust",
          "name": "Trust",
          "category": "personality",
          "percentile": 0.47298674696745124,
          "raw_score": 0.5830101087027785,
          "significant": true
        }
      ]
    },
    {
      "trait_id": "big5_neuroticism",
      "name": "Emotional range",
      "category": "personality",
      "percentile": 0.13904938204251915,
      "raw_score": 0.4595539073395768,
      "significant": true,
      "children": [
        {
          "trait_id": "facet_anger",
          "name": "Fiery",
          "category": "personality",
          "percentile": 0.14592765984036238,
          "raw_score": 0.47807350135271154,
          "significant": true
        },
        {
          "trait_id": "facet_anxiety",
          "name": "Prone to worry",
          "category": "personality",
          "percentile": 0.08697282793529115,
          "raw_score": 0.5013887984737312,
          "significant": true
        },
        {
          "trait_id": "facet_depression",
          "name": "Melancholy",
          "category": "personality",
          "percentile": 0.16680824488529322,
          "raw_score": 0.3872001388285126,
          "significant": true
        },
        {
          "trait_id": "facet_immoderation",
          "name": "Immoderation",
          "category": "personality",
          "percentile": 0.05246097936296118,
          "raw_score": 0.4382727933313163,
          "significant": true
        },
        {
          "trait_id": "facet_self_consciousness",
          "name": "Self-consciousness",
          "category": "personality",
          "percentile": 0.07969774599416085,
          "raw_score": 0.47267337369288276,
          "significant": true
        },
        {
          "trait_id": "facet_vulnerability",
          "name": "Susceptible to stress",
          "category": "personality",
          "percentile": 0.0273807153901362,
          "raw_score": 0.3452475153303576,
          "significant": true
        }
      ]
    }
  ],
  "needs": [
    {
      "trait_id": "need_challenge",
      "name": "Challenge",
      "category": "needs",
      "percentile": 0.08110205321079733,
      "raw_score": 0.669099706309445,
      "significant": true
    },
    {
      "trait_id": "need_closeness",
      "name": "Closeness",
      "category": "needs",
      "percentile": 0.09291402531402237,
      "raw_score": 0.7346366531130437,
      "significant": true
    },
    {
      "trait_id": "need_curiosity",
      "name": "Curiosity",
      "category": "needs",
      "percentile": 0.2183155687091271,
      "raw_score": 0.7961768121584263,
      "significant": true
    },
    {
      "trait_id": "need_excitement",
      "name": "Excitement",
      "category": "needs",
      "percentile": 0.02286176344029084,
      "raw_score": 0.5264979907029215,
      "significant": true
    },
    {
      "trait_id": "need_harmony",
      "name": "Harmony",
      "category": "needs",
      "percentile": 0.03427014251932459,
      "raw_score": 0.7463631682958176,
      "significant": true
    },
    {
      "trait_id": "need_ideal",
      "name": "Ideal",
      "category": "needs",
      "percentile": 0.05741159343084268,
      "raw_score": 0.6161180176812197,
      "significant": true
    },
    {
      "trait_id": "need_liberty",
      "name": "Liberty",
      "category": "needs",
      "percentile": 0.02216408649103313,
      "raw_score": 0.6611766254368321,
      "significant": true
    },
    {
      "trait_id": "need_love",
      "name": "Love",
      "category": "needs",
      "percentile": 0.015052473849888615,
      "raw_score": 0.6631615559158821,
      "significant": true
    },
    {
      "trait_id": "need_practicality",
      "name": "Practicality",
      "category": "needs",
      "percentile": 0.08611576821290123,
      "raw_score": 0.6982802364811073,
      "significant": true
    },
    {
      "trait_id": "need_self_expression",
      "name": "Self-expression",
      "category": "needs",
      "percentile": 0.07504383162546596,
      "raw_score": 0.6253916730109863,
      "significant": true
    },
    {
      "trait_id": "need_stability",
      "name": "Stability",
      "category": "needs",
      "percentile": 0.41330474153377117,
      "raw_score": 0.727472877321253,
      "significant": true
    },
    {
      "trait_id": "need_structure",
      "name": "Structure",
      "category": "needs",
      "percentile": 0.5785073814374321,
      "raw_score": 0.7014458089713079,
      "significant": true
    }
  ],
  "values": [
    {
      "trait_id": "value_conservation",
      "name": "Conservation",
      "category": "values",
      "percentile": 0.16678415814865472,
      "raw_score": 0.6218884680694995,
      "significant": true
    },
    {
      "trait_id": "value_openness_to_change",
      "name": "Openness to change",
      "category": "values",
      "percentile": 0.08647094085994467,
      "raw_score": 0.7317164337859383,
      "significant": true
    },
    {
      "trait_id": "value_hedonism",
      "name": "Hedonism",
      "category": "values",
      "percentile": 0.047762743756957216,
      "raw_score": 0.6316746177041674,
      "significant": true
    },
    {
      "trait_id": "value_self_enhancement",
      "name": "Self-enhancement",
      "category": "values",
      "percentile": 0.00590828237726021,
      "raw_score": 0.5958789067897858,
      "significant": true
    },
    {
      "trait_id": "value_self_transcendence",
      "name": "Self-transcendence",
      "category": "values",
      "percentile": 0.05270413599836593,
      "raw_score": 0.8065859855129559,
      "significant": true
    }
  ],
  "consumption_preferences": [
    {
      "consumption_preference_category_id": "consumption_preferences_shopping",
      "name": "Purchasing Preferences",
      "consumption_preferences": [
        {
          "consumption_preference_id": "consumption_preferences_automobile_ownership_cost",
          "name": "Likely to be sensitive to ownership cost when buying automobiles",
          "score": 1.0
        },
        {
          "consumption_preference_id": "consumption_preferences_automobile_safety",
          "name": "Likely to prefer safety when buying automobiles",
          "score": 1.0
        },
        {
          "consumption_preference_id": "consumption_preferences_clothes_quality",
          "name": "Likely to prefer quality when buying clothes",
          "score": 1.0
        },
        {
          "consumption_preference_id": "consumption_preferences_clothes_style",
          "name": "Likely to prefer style when buying clothes",
          "score": 0.0
        },
        {
          "consumption_preference_id": "consumption_preferences_clothes_comfort",
          "name": "Likely to prefer comfort when buying clothes",
          "score": 1.0
        },
        {
          "consumption_preference_id": "consumption_preferences_influence_brand_name",
          "name": "Likely to be influenced by brand name when making product purchases",
          "score": 0.5
        },
        {
          "consumption_preference_id": "consumption_preferences_influence_utility",
          "name": "Likely to be influenced by product utility when making product purchases",
          "score": 0.0
        },
        {
          "consumption_preference_id": "consumption_preferences_influence_online_ads",
          "name": "Likely to be influenced by online ads when making product purchases",
          "score": 0.0
        },
        {
          "consumption_preference_id": "consumption_preferences_influence_social_media",
          "name": "Likely to be influenced by social media when making product purchases",
          "score": 0.0
        },
        {
          "consumption_preference_id": "consumption_preferences_influence_family_members",
          "name": "Likely to be influenced by family when making product purchases",
          "score": 1.0
        },
        {
          "consumption_preference_id": "consumption_preferences_spur_of_moment",
          "name": "Likely to indulge in spur of the moment purchases",
          "score": 0.0
        },
        {
          "consumption_preference_id": "consumption_preferences_credit_card_payment",
          "name": "Likely to prefer using credit cards for shopping",
          "score": 1.0
        }
      ]
    },
    {
      "consumption_preference_category_id": "consumption_preferences_health_and_activity",
      "name": "Health & Activity Preferences",
      "consumption_preferences": [
        {
          "consumption_preference_id": "consumption_preferences_eat_out",
          "name": "Likely to eat out frequently",
          "score": 0.0
        },
        {
          "consumption_preference_id": "consumption_preferences_gym_membership",
          "name": "Likely to have a gym membership",
          "score": 0.0
        },
        {
          "consumption_preference_id": "consumption_preferences_outdoor",
          "name": "Likely to like outdoor activities",
          "score": 1.0
        }
      ]
    },
    {
      "consumption_preference_category_id": "consumption_preferences_environmental_concern",
      "name": "Environmental Concern Preferences",
      "consumption_preferences": [
        {
          "consumption_preference_id": "consumption_preferences_concerned_environment",
          "name": "Likely to be concerned about the environment",
          "score": 1.0
        }
      ]
    },
    {
      "consumption_preference_category_id": "consumption_preferences_entrepreneurship",
      "name": "Entrepreneurship Preferences",
      "consumption_preferences": [
        {
          "consumption_preference_id": "consumption_preferences_start_business",
          "name": "Likely to consider starting a business in next few years",
          "score": 0.5
        }
      ]
    },
    {
      "consumption_preference_category_id": "consumption_preferences_movie",
      "name": "Movie Preferences",
      "consumption_preferences": [
        {
          "consumption_preference_id": "consumption_preferences_movie_romance",
          "name": "Likely to like romance movies",
          "score": 0.0
        },
        {
          "consumption_preference_id": "consumption_preferences_movie_adventure",
          "name": "Likely to like adventure movies",
          "score": 1.0
        },
        {
          "consumption_preference_id": "consumption_preferences_movie_horror",
          "name": "Likely to like horror movies",
          "score": 0.0
        },
        {
          "consumption_preference_id": "consumption_preferences_movie_musical",
          "name": "Likely to like musical movies",
          "score": 0.0
        },
        {
          "consumption_preference_id": "consumption_preferences_movie_historical",
          "name": "Likely to like historical movies",
          "score": 1.0
        },
        {
          "consumption_preference_id": "consumption_preferences_movie_science_fiction",
          "name": "Likely to like science-fiction movies",
          "score": 1.0
        },
        {
          "consumption_preference_id": "consumption_preferences_movie_war",
          "name": "Likely to like war movies",
          "score": 0.0
        },
        {
          "consumption_preference_id": "consumption_preferences_movie_drama",
          "name": "Likely to like drama movies",
          "score": 1.0
        },
        {
          "consumption_preference_id": "consumption_preferences_movie_action",
          "name": "Likely to like action movies",
          "score": 1.0
        },
        {
          "consumption_preference_id": "consumption_preferences_movie_documentary",
          "name": "Likely to like documentary movies",
          "score": 1.0
        }
      ]
    },
    {
      "consumption_preference_category_id": "consumption_preferences_music",
      "name": "Music Preferences",
      "consumption_preferences": [
        {
          "consumption_preference_id": "consumption_preferences_music_rap",
          "name": "Likely to like rap music",
          "score": 0.0
        },
        {
          "consumption_preference_id": "consumption_preferences_music_country",
          "name": "Likely to like country music",
          "score": 0.5
        },
        {
          "consumption_preference_id": "consumption_preferences_music_r_b",
          "name": "Likely to like R&B music",
          "score": 0.0
        },
        {
          "consumption_preference_id": "consumption_preferences_music_hip_hop",
          "name": "Likely to like hip hop music",
          "score": 0.0
        },
        {
          "consumption_preference_id": "consumption_preferences_music_live_event",
          "name": "Likely to attend live musical events",
          "score": 1.0
        },
        {
          "consumption_preference_id": "consumption_preferences_music_playing",
          "name": "Likely to have experience playing music",
          "score": 0.0
        },
        {
          "consumption_preference_id": "consumption_preferences_music_latin",
          "name": "Likely to like Latin music",
          "score": 1.0
        },
        {
          "consumption_preference_id": "consumption_preferences_music_rock",
          "name": "Likely to like rock music",
          "score": 0.5
        },
        {
          "consumption_preference_id": "consumption_preferences_music_classical",
          "name": "Likely to like classical music",
          "score": 1.0
        }
      ]
    },
    {
      "consumption_preference_category_id": "consumption_preferences_reading",
      "name": "Reading Preferences",
      "consumption_preferences": [
        {
          "consumption_preference_id": "consumption_preferences_read_frequency",
          "name": "Likely to read often",
          "score": 1.0
        },
        {
          "consumption_preference_id": "consumption_preferences_books_entertainment_magazines",
          "name": "Likely to read entertainment magazines",
          "score": 0.0
        },
        {
          "consumption_preference_id": "consumption_preferences_books_non_fiction",
          "name": "Likely to read non-fiction books",
          "score": 1.0
        },
        {
          "consumption_preference_id": "consumption_preferences_books_financial_investing",
          "name": "Likely to read financial investment books",
          "score": 0.0
        },
        {
          "consumption_preference_id": "consumption_preferences_books_autobiographies",
          "name": "Likely to read autobiographical books",
          "score": 1.0
        }
      ]
    },
    {
      "consumption_preference_category_id": "consumption_preferences_volunteering",
      "name": "Volunteering Preferences",
      "consumption_preferences": [
        {
          "consumption_preference_id": "consumption_preferences_volunteer",
          "name": "Likely to volunteer for social causes",
          "score": 1.0
        }
      ]
    }
  ],
  "warnings": [
    {
      "warning_id": "CONTENT_TRUNCATED",
      "message": "For maximum accuracy while also optimizing processing time, only the first 250KB of input text (excluding markup) was analyzed. Accuracy levels off at approximately 3,000 words so this did not affect the accuracy of the profile."
    }
  ]
}

谢谢你的帮助!

Answer 1

您正在初始化一个数组，但随后使用字符串键来设置数据。所以要么使用一个实际的对象：

const setComparisons = {
  jasmine: jasmineData['default'],
  // etc
};

或者使用具有数字索引的数组：

const setComparisons = [
  jasmineData['default'],
  // etc
];

你可以让你的setData和getData保持原样。

它不能按您的方式工作的原因是，数组上的原生toJSON方法只考虑数组中的项，而不考虑对象上可能存在的任何其他属性。此方法在对对象进行字符串化时调用