indexeddb

Khóa học miễn phí IndexedDB – Reading Data nhận dự án làm có lương

Posted on by user

IndexedDB – Reading Data

We enter data into the database, and we need to call the data to view the changes and also for various other purposes.

We must call the get() method on the object store to read this data. The get method takes the primary key of the object you want to retrieve from the store.

Syntax

var request = objectstore.get(data);

Here, we are requesting the objectstore to get the data using get() function.

Example

Following example is an implementation of requesting the objectstore to get the data −

<!DOCTYPE html>
<html lang="en">
<head>
   <title>Document</title>
</head>
<body>
   <script>
      const request = indexedDB.open("botdatabase",1);
      request.onupgradeneeded = function(){
         const db = request.result;
         const store = db.createObjectStore("bots",{ keyPath: "id"});
      }
      request.onsuccess = function(){
         document.write("database opened successfully");
         const db = request.result;
         const transaction=db.transaction("bots","readwrite");
         const store = transaction.objectStore("bots");
         store.add({id: 1, name: "jason",branch: "IT"});
         store.add({id: 2, name: "praneeth",branch: "CSE"});
         store.add({id: 3, name: "palli",branch: "EEE"});
         store.add({id: 4, name: "abdul",branch: "IT"});
         const idquery = store.get(4);
         idquery.onsuccess = function(){
            document.write("idquery",idquery.result);
         }
         transaction.oncomplete = function(){
            db.close;
         }
      }
   </script>
</body>
</html>

Output

database opened successfully
idquery {id: 4, name: ''abdul'', branch: ''IT''}

Khóa học lập trình tại Toidayhoc vừa học vừa làm dự án vừa nhận lương: Khóa học lập trình nhận lương tại trung tâm Toidayhoc

user