AppStorage

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appStorage.getItem(key, callback)
appStorage.getAllItems(key, callback)

Description

appStorage allows you to get data in key, value pairs from the server. Data is maintained in the Volt Dashboard. This is useful for data you want to share with all users of your app: announcements, shared tables which change from time to time, dates or even code.

The value returned is a string. There is no size limit on value, other than it be reasonable.

This feature is only available if your app is hosted on Volt.

If your app does not have a live internet connection, the request will time out and an error message will be passed to callback.

Since the calls access information on a server, they are asynchronous (so your app does not look up while the call is being processed). When the call is complete, the function named in callback is called in your app. It passes two parameters: (error, data). If the call is successful, error is empty and your results are in data. If the call is unsuccessful, error is not empty and the error message is in data.message.

appStorage is an alias for $volt.storage in the Volt API.

Properties and Methods

clear(callback) Clear all entries for the app. Dashboard only.
getItem(key, callback) Get the item which is saved under key. String.
getAllItems(callback) Gets all the items for the app, as an array. Each element is a key,value pair.
removeItem(key, callback) Deletes item key. Dashboard only.
setItem(key, value, callback) Sets item key to value. Creates item if it does not exist. Dashboard only.

Example - BASIC

Function butGetAllItemsApp_onclick()
  appStorage.getAllItems(getAllItemsCallback)
End Function

Function butGetItemApp_onclick()
  appStorage.getItem("SimpleString", getItemCallback)
End Function

Function getAllItemsCallback(error, data) 
  If error Then
    If data = undefined Then data = {message: "Network Error"}
    MsgBox data.message
  Else
    Print False
    For Each key in data
      console.log(key, data[key])
      k = [key, key][0]
      Print k & ": " & data[key].toString()
    Next
    End If
End Function

Function getItemCallback(error, data) 
  If error Then
    If data = undefined Then data = {message: "Network Error"}
    MsgBox data.message
  Else
    MsgBox data
  End If
End Function

Example - JavaScript

butGetAllItemsApp.onclick = function() {
     appStorage.getAllItems(getAllItemsCallback);
 };

 butGetItemApp.onclick = function() {
     appStorage.getItem("SimpleString", getItemCallback);
 };

function getAllItemsCallback(error, data) {
    if (error) {
        if (data == undefined) {
            data = {
                message: "Network Error"
            };
        }
        NSB.MsgBox(data.message);
    } else {
        NSB.Print((false) + "<br>");
        for (key in data) {
            console.log(key, data[key]);
            k = [key, key][0];
            NSB.Print(((k) + (": ") + (data[key].toString())) + "<br>");
        }
    }
}

function getItemCallback(error, data) {
    if (error) {
        if (data == undefined) {
            data = {
                message: "Network Error"
            };
        }
        NSB.MsgBox(data.message);
    } else {
        NSB.MsgBox(data);
    }
}

Output

(see appStorage sample)

Related Items

LocalStorage, SessionStorage, ServerStorage, SQL