如何删除本地存储中的数据

Question

我需要什么

我需要在点击时切换图像。
就像如果用户 select 最喜欢的选择 & 然后它标记不喜欢的图像被更改并且数据从 localstoarge 中删除。

html代码

<div  style="display:block; float:right; width:auto; color:#7c7c7c;">
    <a href="javascript:void(0);" class="favourate_dextop" id="fav'.$data[$k]['id'].'"  onClick=" favaorite('.$data[$k]['id'].',\''.$name_event.'\',\''.$event_city.'\',\''.$event_country.'\',\''.$event_urls.'\',this)"></a>
</div>

js代码

function favaorite(sess_id,name,city,country,event_url,pointer){

    var eventData;
    //is anything in localstorage?
    if (localStorage.getItem('eventData') === null) {
        eventData = [];
    } else {
        // Parse the serialized data back into an array of objects
        eventData = JSON.parse(localStorage.getItem('eventData'));
        //alert(eventData);
        $.each(eventData, function(key, value){
            //console.log(value);
            var  imageUrl='http://im.gifbt.com/images/star1_phonehover.png';
            //var  imageUrl='http://im.gifbt.com/images/star1_phone.png';

            $(pointer).closest('.evt_date').find('.favourate_dextop').css('background-image', 'url("' + imageUrl + '")');
            //$(pointer).closest('.evt_date').find('.favourate_dextop').css('background-image', 'url("' + imageUrl + '")');
        });

    }
    var details={};

    details.sess_id=sess_id;
    details.name=name;
    details.city=city;
    details.country=country;
    details.event_url=event_url;

    // Push the new data (whether it be an object or anything else) onto the array
    eventData.push(details);

    // Alert the array value
    //alert(eventData);  // Should be something like [Object array]
    // Re-serialize the array back into a string and store it in localStorage
    var jsondata=localStorage.setItem('eventData', JSON.stringify(eventData));


}

问题

我是本地存储的新手，我需要知道如何从 json 字符串中删除数据。
我已经实现了添加到收藏夹，现在我需要标记为不喜欢。

数据存储：

[{
    "sess_id":182104,
    "name":"AUTOMECH FORMULA",
    "city":"Cairo",
    "country":"Egypt",
    "event_url":"automech-formula"
},]

Answer 1

要从本地存储中删除数据，请使用 localStorage.removeItem('itemNam')

示例

localStorage.setItem('name','hello');

从您使用的 localStorage 中删除名称项

localStorage.removeItem('name');

但如果您的问题是如何从 JSON 对象中删除数据，那么您有两种方法

1：改变原来的json对象

删除originalJson.attributeName

   originalJson = {name:'myname',age:30};//our object to test with

示例：

   delete originalJson.age //in this case originalJson.age is no more available

2：不要更改原始对象，而是制作另一个副本

originalJson2 = JSON.stringify(originalJson);
  originalJson2 = JSON.parse(originalJson2);
  delete originalJson2.age //originalJson.age is available but originalJson2.age is not available

这里是：jsfiddle

Answer 2

假设 sess_id 是您的事件的唯一 ID

function unfavorite(sess_id){

    var eventData = localStorage.getItem('eventData');

    //is anything in localstorage?
    if (localStorage.getItem('eventData') === null) {
        console.log('invalid event');
    } 
    eventData = JSON.parse(eventData);

    // Keep all without the one with specified sess_id
    $.grep(eventData, function(value) {
       return value.sess_id != sess_id;
    });

    var jsondata=localStorage.setItem('eventData', JSON.stringify(eventData));
}

如何删除本地存储中的数据

How to To Delete The data in Localstorage

javascript

php

jquery

local-storage