校驗值，但顯示未定義

Question

小提琴是here

我在下面的結構localStorage.COMMENT_DESCRIPTION.list_no增加值，但它始終顯示未定義。

但是，當我打印到console.log它顯示的數據。問題是，當我與條件檢查它不工作

var comment_description = {}; 
$("#add_list_img").click(function() 
{ 
    if(localStorage.COMMENT_DESCRIPTION) 
    { 
     alert(localStorage.COMMENT_DESCRIPTION.list_no); # Here is the problem. I have added the value but the variable is empty 
     if(localStorage.COMMENT_DESCRIPTION.list_no == undefined) 
     { 
      alert("Here so"); 
      cart_val = localStorage.COMMENT_DESCRIPTION.list_no || 1; 
      comment_description.list_no = cart_val+1; 
      console.log(comment_description); 
      storage(); 
     } 
     else 
     { 
      alert("here");   

      cart_val = comment_description.list_no; 
      comment_description.list_no = cart_val+1; 
      storage(); 
     } 
    } 
    else 
    { 

     cart_val = 1; 
     comment_description.list_no = cart_val+1; 
     storage(); 
    } 

}); 

function storage() 
{ 
    if(localStorage.COMMENT_DESCRIPTION) 
    { 
     var oldItems = JSON.parse(localStorage.getItem('COMMENT_DESCRIPTION')); 
     console.log("strogae "+comment_description.list_no); 
     var newItems = $.extend({}, oldItems, comment_description); 
     localStorage.setItem('COMMENT_DESCRIPTION',JSON.stringify(newItems)); 

    } 
    else 
    { 
     var lc_no = {"list_no":1,"card_no":1}; 
     var newItems = $.extend({},comment_description); 
     localStorage.setItem('COMMENT_DESCRIPTION',JSON.stringify(newItems)); 
    } 

     console.log("added following"+localStorage.COMMENT_DESCRIPTION); 
} 

Answer 1

你需要分析它首先

JSON.parse(localStorage.COMMENT_DESCRIPTION).list_no 

的內容你localStorage.COMMENT_DESCRIPTION是JSON字符串沒有對象

你的

訂正工作撥弄

https://jsfiddle.net/cyauyg0k/3/