IndexedDB - 读取数据
我们将数据输入到数据库中，我们需要调用数据来查看变化以及其他各种目的。
我们必须调用对象存储上的get()方法来读取此数据。 get 方法获取要从存储中检索的对象的主键。
语法
var request = objectstore.get(data);
在这里，我们使用 get() 函数请求对象存储来获取数据。
示例
下面的例子是请求objectstore获取数据的实现 −
<!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>
输出
database opened successfully
idquery {id: 4, name: 'abdul', branch: 'IT'}
