Now the code below demonstrate the complete operations of indexedDB.
[html]
<!DOCTYPE html>
<html>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=utf-8" />
<script type="text/javascript">
window.indexedDB = window.indexedDB || window.mozIndexedDB || window.webkitIndexedDB || window.msIndexedDB;
window.IDBTransaction = window.IDBTransaction || window.webkitIDBTransaction || window.msIDBTransaction;
window.IDBKeyRange = window.IDBKeyRange || window.webkitIDBKeyRange || window.msIDBKeyRange
if (!window.indexedDB) {
window.alert("Your browser doesn't support a stable version of IndexedDB.")
}
const employeeData = [
{ id: "00-01", name: "John", age: 35, email: "john@splessons.com" },
{ id: "00-02", name: "Robort", age: 32, email: "prasad@splessons.com" }
];
var db;
var request = window.indexedDB.open("newDatabase", 1);
request.onerror = function(event) {
console.log("error: ");
};
request.onsuccess = function(event) {
db = request.result;
console.log("success: "+ db);
};
request.onupgradeneeded = function(event) {
var db = event.target.result;
var objectStore = db.createObjectStore("employee", {keyPath: "id"});
for (var i in employeeData) {
objectStore.add(employeeData[i]);
}
}
function read() {
var transaction = db.transaction(["employee"]);
var objectStore = transaction.objectStore("employee");
var request = objectStore.get("00-03");
request.onerror = function(event) {
alert("Unable to retrieve daa from database!");
};
request.onsuccess = function(event) {
// Do something with the request.result!
if(request.result) {
alert("Name: " + request.result.name + ", Age: " + request.result.age + ", Email: " + request.result.email);
}
else {
alert("Johnny couldn't be found in your database!");
}
};
}
function readAll() {
var objectStore = db.transaction("employee").objectStore("employee");
objectStore.openCursor().onsuccess = function(event) {
var cursor = event.target.result;
if (cursor) {
alert("Name for id " + cursor.key + " is " + cursor.value.name + ", Age: " + cursor.value.age + ", Email: " + cursor.value.email);
cursor.continue();
}
else {
alert("No more entries!");
}
};
}
function add() {
var request = db.transaction(["employee"], "readwrite")
.objectStore("employee")
.add({ id: "00-03", name: "Johnny", age: 19, email: "Johnny@planet.org" });
request.onsuccess = function(event) {
alert("Johnny has been added to your database.");
};
request.onerror = function(event) {
alert("Unable to add data\r\nJohnny is aready exist in your database! ");
}
}
function readAll() {
var objectStore = db.transaction("employee").objectStore("employee");
objectStore.openCursor().onsuccess = function(event) {
var cursor = event.target.result;
if (cursor) {
alert("Name for id " + cursor.key + " is " + cursor.value.name + ", Age: " + cursor.value.age + ", Email: " + cursor.value.email);
cursor.continue();
}
else {
alert("No more entries!");
}
};
}
</script>
</head>
<body>
<button onclick="read()">Read </button>
<button onclick="readAll()">Read all </button>
<button onclick="add()">Add data </button>
<button onclick="remove()">Delete data </button>
</body>
</html>
[/html]
Result
By running the above code in a preferred browser following output is obtained.
By clicking the above buttons employee details are added and removed as shown in the below image.
When clicked on
OK button, another employee details are obtained as shown in the below image.