如何删除Localstorage中的数据


How to To Delete The data in Localstorage

我需要什么

  • 我需要在点击时切换图像
  • 喜欢如果用户选择最喜欢的选择&然后它标志着不利的图像被更改,数据被从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,现在我需要标记不受欢迎

存储数据:

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

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

示例

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

要从本地存储中删除名称项目,请使用

localStorage.removeItem('name');

但是,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:更改原始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

这是:jsfiddle

假设sess_id是事件的唯一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));
}