Question

我刚开始使用indexedDB。

我能够在对象Store中写入数据，并在第一次点击它时获取数据。当我试图再次点击时，我发现它可以将数据写入数据库，但似乎无法调用OpenCursor.Success。

任何人都可以指出差距吗？

这是我的代码..

function clickMe()
{
alert("Yes am inside the function..");
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;

try {
  var dbOpenRequest = window.indexedDB.open("MyDB");
  alert("congretss I Opened The DB as well..");

  dbOpenRequest.onsuccess = function(event){
  try {
     alert("I am inside the onsuccess Method");
     var db = dbOpenRequest.result;
     db.onerror=function(event){

     }; 

     var transaction = db.transaction(["My_ObjectStore"], "readwrite");

      transaction.oncomplete = function(e){

      };
      transaction.onabort = function(e){

      };
      transaction.onerror = function(e){

      };


      try {
        var objectStore = transaction.objectStore("My_ObjectStore");
       alert("Wait am trying to write the data in DB..");
        var objectId = new Date().getTime()
                    var data =([ {
                    "reference": "<a href='details.html'>DEV2014/557</a>",
                    "applicant": "Association",
                    "siteAddress": "631 Gregory Terrace, Bowen Hills",
                    "applicationType": "Decided Application",
                    "status": "Approved",
                    "action": "<a href='details.html' class='btn btn-primary'>View Details</a>",
                    "id": 1
                    },
                     {
                    "reference": "<a href='details.html'>DEV2014/557</a>",
                    "applicant": "Association",
                    "siteAddress": "631 Gregory Terrace, Bowen Hills",
                    "applicationType": "Decided Application",
                    "status": "Approved",
                    "action": "<a href='details.html' class='btn btn-primary'>View Details</a>",
                    "id": 2
                    }
                    ]);

        for(i in data)
        {
        var request = objectStore.add(data[i]);  
        }
        alert("Writing data is finished.."+request);

        //get all the data using cursor 
        objectStore.openCursor().onsuccess = function(event) {
        alert("Now you can See the Data..");
         var cursor = event.target.result;

         if (cursor) {
            alert(cursor.value.id);

            cursor.continue();
            } 
             else {
            //alert("No more entries!");
                }     
           };   

        }catch(e){alert("error while writting the data");}



    }catch (e){         
            alert("An error occured when creating object store");
            writeError(e);
            }
     };

 dbOpenRequest.onupgradeneeded = function(event){
 try{
     var db = dbOpenRequest.result;
     var transaction = dbOpenRequest.transaction;
     var objectStore = db.createObjectStore("My_ObjectStore",{
        "keyPath": "id",
        "autoIncrement": true
      });
       }catch(e){alert("Error while crating object store");}
    };
  }
catch(e){alert("error");}
}

Answer 1

我观察到将数据写入DB
就可以了

我只是复制/粘贴并测试了您的代码，第一次写入运行正常，但其他人没有（您可以使用浏览器调试工具查看indexeddb内容）。

原因：您每次都设置相同的主键：

"id": 1
"id": 2

所以我无法解释为什么你的打开游标失败后（可能是因为你的对象存储请求进入错误状态？），但似乎是问题...

objectStore.openCursor（）。onsuccess没有被调用

1 个答案: