Send alert if item has already been selected

Maureen Moore

public onSubmit(id, product_name){
var data = {
id,
product_name
};
this.items.push(data);
localStorage.setItem(this.storageKey, JSON.stringify(this.items));
var retrieverObject = localStorage.getItem('this.items.id');
var retrieveObject = JSON.parse(retrieverObject);
if (retrieveObject == id) {
alert('test');
}
}

I want to check if the value has already been submitted. This is part of a shopping cart application in which the product quantity will be updated if the product has already been chosen.

When I use

var retrieverObject = localStorage.getItem('MyDataStorageKey');

it returns:

[{"id":0,"product_name":"Adult Male Bike"},{"id":0,"product_name":"Adult Male Bike"}]

All of the following return null

var retrieverObject = localStorage.getItem('MyDataStorageKey.findIndex(id)');
var retrieverObject = localStorage.getItem('MyDataStorageKey.indexOf("id")');
var retrieverObject = localStorage.getItem('MyDataStorageKey.indexOf(id)');
var retrieverObject = localStorage.getItem('MyDataStorageKey[0].id');
var retrieverObject = localStorage.getItem('MyDataStorageKey[0]');
var retrieverObject = localStorage.getItem('MyDataStorageKey.findIndex("id")');
var retrieverObject = localStorage.getItem('MyDataStorageKey["id"]');
var retrieverObject = localStorage.getItem('MyDataStorageKey.id');

4 Replies

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Maureen Moore6y ago
This is the solution:
var retrieverObject = localStorage.getItem('items');
var retrieveObject = JSON.parse(retrieverObject);
if(retrieveObject === null) {
console.log('no tasks')
} else {
retrieveObject.forEach(function(el){
alert("This is the storage id " + el.id);
if (el.id == id){
alert(el.id + " same ");
}
});
}
+1
Maureen Moore6y ago
All of these return null:
var retrieverObject = localStorage.getItem('items["id"]');
var retrieverObject = localStorage.getItem('items[0].id');
var retrieverObject = localStorage.getItem('items[{"id"}]');
+1
Maureen Moore6y ago
This is an angular app not using jQuery. I can't use the jQuery filter. Thanks anyways Nisha.
+1
Nisha Regil6y ago
You can use jquery filter like this

var filterarray = retrieveObject.filter(function (data) {
return data.id === id ;
});

if data with id already exists filterarray will return length > 0.

Also I have a doubt in the var retrieverObject statement you wrote. At one place you are assinging it to localStorage.getItem('this.items.id'); and in another to localStorage.getItem('MyDataStorageKey');
+1