The difference between setstoragesync and setstorage

I have always liked to use native local storage in browsers , I used it a lot before . Developed a few days ago uniapp, Use the browser's native local storage , No problem in the browser , But packaged into app It can't be used . Later on uniapp Official local storage , Can be used after packaging , It has to be said that the official is , But the first time I used it , This synchronization and asynchronism makes me a little confused . But the existence of synchronous and asynchronous , There must be a reason .

Let's start with the official definition ：

uni.setStorage(OBJECT)

Store the data in the local cache specified key in , Will cover up the original key Corresponding content , This is an asynchronous interface .

uni.setStorage({
    key: 'storage_key',
    data: 'hello',
    success: function () {
        console.log('success');
    }
});

uni.setStorageSync(KEY,DATA)

take data Store... Specified in the local cache key in , Will cover up the original key Corresponding content , This is a synchronous interface .

uni.setStorageSync('storage_key', 'hello');

  Just look at the way it is written , The synchronous interface is easy to use , Follow js Native storage is no different , Save key value pairs . The asynchronous interface can receive callback after accessing data .

Next , Let's try it .

uni.setStorage({
	key:'ghui',
	data:' I'm dregs and dregs ',
	success() {
		uni.showToast({
			title:' Saved successfully '
		});
	}
});
			
let ghui = uni.getStorage({
	key:'ghui'
})

let GHUI = uni.getStorageSync('ghui');

console.log(ghui,GHUI);

The console results are as follows ：

Then I changed it ：

uni.getStorage({
	key:'ghui',
	success(res) {
		console.log(res);
	}
})

  That is to say , The asynchronous interface fetches the returned results from the cache , Can only be used in successful callbacks , The feature is that after getting the cached data, you don't have to wait for irrelevant logic to complete , Just execute the relevant logic directly , faster , But it's nested in layers 、 Not beautiful . Recall the first time the console printed promise, I seem to think of something .

uni.getStorage({
	key:'ghui',
}).then(res => {
	console.log(res);
})

Sure enough , Yes. , But what you get is an array , There is a second item in the data ：

  In this case , You can avoid nesting layers . And the synchronization interface , Apart from being easy to write , He can assign a value to a variable , It's easy to use , And it is executed synchronously , There is no need to consider the following logic problems when the cache is not fetched , Used to be the same as the original , There will be no more writing , He that talks much errs much .

One sided understanding , No, I hope you guys can give me more advice .