• indexedDB 使用


    数据库的打开/新增/删除

    initDB() {
      let _this = this;
      let obj = {
        id: 1,
        name: _this.addForm.content
      }
      let indexedDB = window.indexedDB || window.webkitindexedDB || window.msIndexedDB || mozIndexedDB;
      request = indexedDB.open('edp'); //edp数据库名称
      request.onsuccess = function(event) {
        console.log('打开成功');
        db = event.target.result;
        //清空表
        //let tx = db.transaction('messageCode', 'readwrite');
        //let store = tx.objectStore('messageCode');
        //store.clear();
        // 删除表
          let tx = db.transaction('messageCode', 'readwrite');
          let store = tx.objectStore('messageCode');
          store.delete(1);     
    //添加表     let objStore;     let transaction = db.transaction(['messageCode'], 'readwrite');     objStore = transaction.objectStore('messageCode');     objStore.add(obj);   }   request.onupgradeneeded = function(event) {     db = event.target.result;     let store;     //创建表     if(!db.objectStoreNames.contains('messageCode')) {       store = db.createObjectStore('messageCode', {         keyPath: 'id',         autoIncrement: true       });     }     console.log('创建对象仓库成功');   } }

    更改表

    //内容更改
    changeCode() {
        let obj = {
            id: 1,
            name: this.addForm.content
        }
        //更新表
        let tx = db.transaction('messageCode', 'readwrite');
        let store = tx.objectStore('messageCode');
        let req = store.get(1);
        req.onsuccess = function(e) {
            store.put(obj);
            console.log('更新成功');
        };
    },            

    新页面获取表

    created() {
        let _this = this;
        var request = window.indexedDB.open('edp');
        var db;
        request.onerror = function() {
            console.log('数据库打开报错');
        }
        request.onsuccess = function(event) {
            console.log('数据库打开成功');
        db = event.target.result;
        var transaction = db.transaction(['messageCode'], 'readwrite');
        var objStore = transaction.objectStore('messageCode');
        // 读取数据
        var req = objStore.get(1);
        req.onsuccess = function(e) {
            if(req.result) {
                    console.log('已经查询到数据为:');
            console.log(req.result);
            _this.online = req.result.name;
            } else {
            console.log('未查询到数据');
            }
        }
        }
        request.onupgradeneeded = function(event) {
            console.log('数据库升级事件');
            db = event.target.result;
            console.log(db);
        }
    }        
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  • 原文地址:https://www.cnblogs.com/zhaozhenzhen/p/12106539.html
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