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Remove array item from localstorage

I have an array i stored(parsed it as json) in localstorage. I got it back into an object, removed some items from it and i need to update the key with the new values in the local storage.

var counter = [0,1,2];
var count = counter[0];
var questions = localStorage.getItem('questions');///questions had been stored in local storage with another function
console.log(questions);
questions = $.parseJSON(questions);

if (questions != 0){
    $('.question').html(questions[count]['question']);
    var options = (questions[count]['options']);
    options.forEach(function (item) {
        $('.options').html(item);
    });
    var index = counter.indexOf(1);
    questions = questions.splice(index, 1);
    console.log(questions);
    localStorage.removeItem('questions);
    counter = counter.splice(index, 0);

Now, when i remove the question key from the local storage, the whole question array is deleted, however, i only need to delete the particular question array that was passed.

like image 670
Fadil Olamyy Wahab Avatar asked Aug 03 '16 15:08

Fadil Olamyy Wahab


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2 Answers

Instead of deleting the key, just set it again with the new questions array:

questions.splice(index, 1);
localStorage.setItem('questions', JSON.stringify(questions));
like image 116
tenhsor Avatar answered Nov 14 '22 21:11

tenhsor


Don't use removeItem() that as the name says removes the whole item from localStorage. Just do another setItem() to overwrite the old data.

Also you do:

questions = questions.splice(index, 1);

That is going to remove element(s) from the array and return them. questions will then be the removed element(s) and not your modified array. By your question you just want the modified array. So just do the splice() without the assignment

So your end code would be:

questions.splice(index, 1);
localStorage.setItem('questions',JSON.stringify(questions));
like image 35
Patrick Evans Avatar answered Nov 14 '22 23:11

Patrick Evans