Version: Smart Feature Phone 2.5

DataStore.getLength()

The getLength() method of the DataStore interface returns the number of records stored in the current data store.

Syntax#

store.getLength().then(function(storeLength) {
  // Do something with storeLength
});

Returns#

A Promise object of type unsigned long that resolves with a numeric variable containing the number of records stored in the current data store.

Example#

In the following example, we use navigator.getDataStores to return a list of DataStore objects representing data stores on the device called contacts. Since there is only one such data store, we can access it inside the outer promise using stores[0]. The next promise uses DataStore.getLength to return the number of records in the store. If the value is 0, we populate the data store with records contained in the contactsInit object; if there is already data in the store, we run DataStore.sync to loop through any additions since the code last accessed the data store and update the data display as necessary.

navigator.getDataStores('contacts').then(function(stores) {
  stores[0].getLength().then(function(storeLength) {
    if(storeLength == 0) {
        for(i = 0; i < contactsInit.length; i++) {
        addContact(stores[0],contactsInit[i]);  
      };
    } else {
      var cursor = stores[0].sync();
      runNextTask(cursor);
    }
  });
});