function getProperty(property)
{
console.log(localStorage[property]) //Displays “null”
if(localStorage[property] == null)
{
console.log('Null check')
return false;
}
return localStorage[property];
}
The log outputs "null", but the 'if()' condition does not work. I have tried using ===, but it still doesn't work. Can someone please help?
UPDATE: Thank you to everyone who helped me, this change did the trick
if(localStorage[property] == 'null')When using localStorage, the keys and values are always stored in UTF-16 string format, which uses two bytes per character. Integer keys are automatically converted to strings, similar to objects.
Check out this link for more information on Window.localStorage
Here is a simple example you can try:
localStorage[property] === 'null'
While
console.log(localStorage[property])null, the real value is actually undefined.
Therefore, in your if statement, if you check for undefined, you will find a match.
Even better, simply check for the presence or absence of a value with:
If(localStorage[property])... // Checks for any "truthy" value
or
If(!localStorage[property])... // Checks for any "falsey" value
It's always important to clarify whether you are referring to the global localStorage or if it's a variable defined within your code.
If you are utilizing the localStorage API, make sure to confirm the existence of a key using the following approach...
if (!localStorage.getItem("my-item")) {
console.log("item doesn't exist.");
}
The .getItem() method will return null if the key is not set, hence using either ! or item !== null for verification purposes.
For more information on
.getItem(), check out the reference on MDN: https://developer.mozilla.org/en-US/docs/Web/API/Storage/getItem.
To retrieve an item from localStorage, you can use the getItem() function in this way:
if(!localStorage.getItem(property) || localStorage.getItem(property)===null){
// This property does not exist in localStorage
}
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