Question

I am currently data into a local db as following:

    window.localStorage.setItem('QQIDVAL' + ID, JSON.stringify(this));

How do I go about then retrieving all of the data that is in the localstorage and looking for ones that start with “QQ”

Also how do I go about selecting which columns I want to retreive as JSON.stringify(this) has a lot of columns but I only need a subset of those.

Answer 1

You can take advantage of the fact that localStorage is treated like an object and do something like this (iterating through the keys and checking their name):

​for(dataObj in localStorage) {
    if(dataObj.charAt(0) == Q && dataObj.charAt(1) == Q) {
        // do whatever with your data object, it starts with QQ
        var myObj = localStorage[dataObj];
    }
}​

You could also change the if statement to this:

if(dataObj.substr(0,2) == "QQ") { // do your thing

Don’t have a reference to the substr() documentation right now though, don’t recall if that’s the correct syntax.