how to retrieve data from local storage?

问题:

I have created a register form using javascript from which data is getting stored in the local storage,but I want to retrieve data from local storage for login purpose, following is my controller.js-

//Storing data from local storage into an array of objects
 var usersdata = JSON.parse( localStorage.getItem('key_users' ) );
function validatelogin()
{
    usersdata = JSON.parse( localStorage.getItem('key_users' ) );
    var usernameinput   = document.getElementById("username");
    var passwordinput   = document.getElementById("password");
    for(var p in userdata)
    {
      console.log(p+':'+userdata[p].username+'|'+userdata[p].email);
      if(usernameinput==userdata[p].username && passwordinput==userdata[p].password)
      {
         alert("Logged in successfully");
      }
    }
}

While trying to login, its giving error called 'userdata' is not defined..Please help with whats wrong in the code?

回答1:

Inside the for loop change userdata to usersdata

回答2:

You can easily retrieve data using

var myData = localStorage.getItem('myDataStorage');

But before you even do that you should set the localstorage first

localStorage.setItem('myDataStorage', JSON.stringify(myData));

and then you retrieve from the same local storage using getItem and then specifying the name of the created localStorage item.