Why doesn't adding/removing items in "LocalStorage" work?

Question

JavaScript

• When I add: the name, phone and mail of the user in localSrorage using the method: addContact(), in order to create a table from the data that is in localStorage, the method: show(). Then I get an error when adding: Uncaught TypeError: Cannot read property 'value' of undefined
  
• Also there is no deletion of the contact, I'm trying to do it with the method: deleteContact(e). And I get this error: Uncaught TypeError: Cannot read property 'splice' of undefined
  

My code

Answer 1

It falls right here
because when initializing localStorage['addbook'] = "", and it cannot convert this to json.