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What if you wanted to get all the videos out of the store? Using
the get method won't cut it. We need to iterate through the
entire data store:
var transaction = db.transaction(['blockbusters'],READ_WRITE),
store = transaction.objectStore('blockbusters'),
data = [];
var request = store.openCursor();
request.onsuccess = function (event) {
var cursor = event.target.result;
if (cursor) {
// value is the stored object
data.push(cursor.value);
// get the next object
cursor.continue();
} else {
// we've got all the data now, call
// a success callback and pass the
// data object in.
}
};
In this code block, we're opening up our object store as usual,
but instead of executing a get we open a cursor. This allows us
to cycle through each stored object. We could easily use this
process to find all the videos with a rating of five or more stars
by adding a nested check against
cusor.value.rating
before
pushing the current stored object onto our
data
array of results.
For example:
function find(filter, callback) {
// READ_WRITE was declared earlier on in our code
var transaction = db.transaction(['blockbusters'],
¬ READ_WRITE),
store = transaction.objectStore('blockbusters'),
data = [];
var request = store.openCursor();
request.onsuccess = function (event) {
var cursor = event.target.result;
if (cursor) {
if (filter(cursor.value) === true) {
