javascript - 在 indexedDB 中检索数据时出现错误 "A mutation operation was attempted on a database that did not allow mutations."

Question

我有这个简单的示例代码:

var request = mozIndexedDB.open('MyTestDatabase');
request.onsuccess = function(event){
  var db = event.target.result;
  var request = db.setVersion('1.0');
  request.onsuccess = function(event){
    console.log("Success version.");
    if(!db.objectStoreNames.contains('customers')){
      console.log("Creating objectStore");
      db.createObjectStore('customers', {keyPath: 'ssn'});
    }
    var transaction = db.transaction([],  IDBTransaction.READ_WRITE, 2000);
    transaction.oncomplete = function(){
      console.log("Success transaction");
      var objectStore = transaction.objectStore('customers');
    };
  };
};

我得到这个:

A mutation operation was attempted on a database that did not allow mutations." code: "6

在线

var objectStore = transaction.objectStore('customers');

无法弄清楚 - 我做错了什么？

Answer 1

您只能在版本更改事务中创建或删除对象存储

参见:https://developer.mozilla.org/en-US/docs/IndexedDB/IDBDatabase