Only getting the last entered value when storing a value in sessionStorage.setitem

Question

Okay lets say i enter these two values in my HTML page: 20, 30.

I have these two variabels, i get the value from my HTML page, and it works fine, so BrugerFugt=20, and BrugerTemp=30:

    BrugerFugt = document.getElementById("40").value;
    BrugerTemp = document.getElementById("41").value;

Then i take these two variabels and use setItem.

    sessionStorage.setItem("BF", JSON.stringify(BrugerFugt));
    sessionStorage.setItem("BT", JSON.stringify(BrugerTemp));

At this point if i console.log(JSON.stringify(BrugerFugt)), it's printing 20, as it should.

Now i want to send this to my server, so i call this variable:

  serverConnection.send(JSON.stringify(SetBruger));

I have defined this variable, that i'm sending to my server.

var SetBruger = {
    command: "BrugerIndtastTF",
    brugerT: sessionStorage.getItem("BT"),
    brugerF: sessionStorage.getItem("BF")
}

Then i tryed to print my JSON.stringify(SetBruger), but it's printing the last value i entered on my HTML web, not the new. Let's say before i entered 20 and 30, i entered somthing like 40 and 60. Then when i print my SetBruger after i've entered 20 and 30, i get this print in my termiinal.

test: {"command":"BrugerIndtastTF","brugerT":"\"40\"","brugerF":"\"60\""}

It's like the problem occurs, when i JSON.stringify(SetBruger)?

Answer 1

Your object-properties are set when the object is created.

var SetBruger = {
    command: "BrugerIndtastTF",
    brugerT: sessionStorage.getItem("BT"), // set when object is created
    brugerF: sessionStorage.getItem("BF") // set when object is created
}

You can wrap that object with an helper-function that updates the object prior return or replace it with a function that returns an freshly created object with the values from sessionStorage like this:

function SetBruger() {
  return {
    command: "BrugerIndtastTF",
    brugerT: sessionStorage.getItem("BT"),
    brugerF: sessionStorage.getItem("BF")
  }
}
serverConnection.send(JSON.stringify(SetBruger));

To be able to re-use that object and update other properties of it, a helper function that updates the two properties with the content of localstorage would be a good solution.

var SetBruger = {
    command: "BrugerIndtastTF",
    brugerT: sessionStorage.getItem("BT"), // set when object is created
    brugerF: sessionStorage.getItem("BF") // set when object is created
}

// Other code that maybe modify the object

function updateBrugerObject() {
    SetBruger.brugerT = sessionStorage.getItem("BT");
    SetBruger.brugerF = sessionStorage.getItem("BF");
}

updateBrugerObject();
serverConnection.send(JSON.stringify(SetBruger));

what the best solution for you is, depends on how and where you plan to use the object.