1 //    webSQL
 2 function createDbSuccess() {
 3     console.log(‘创建数据库成功‘);
 4 }
 5 //创建数据库
 6 //数据库名称 版本号 描述文本 数据库大小 回调函数
 7 var db = openDatabase(‘db27‘, ‘1.0‘, ‘Test DB‘, 2 * 1024 * 1024,createDbSuccess());
 8 var msg;
 9 var dbId=4;
10 var dbName=‘jack‘;
11 db.transaction(function (tx) {
12 //创建表
13     tx.executeSql(‘CREATE TABLE IF NOT EXISTS LOGS (id unique, log)‘);
14     //增
15     tx.executeSql(‘INSERT INTO LOGS (id, log) VALUES (1, "菜鸟教程")‘);
16     tx.executeSql(‘INSERT INTO LOGS (id, log) VALUES (2, "www.runoob.com")‘);
17     tx.executeSql(‘INSERT INTO LOGS (id, log) VALUES (3, "jayson")‘);
18     tx.executeSql(‘INSERT INTO LOGS (id,log) VALUES (?, ?)‘, [dbId, dbName]);
19 
20 
21     msg = ‘<p>数据表已创建，且插入了两条数据。</p>‘;
22     // document.querySelector(‘#status‘).innerHTML =  msg;
23     document.getElementById(‘status‘).innerHTML=msg;
24 });
25 //删
26 //sql语句 参数变量 成功的回调 失败的回调
27 db.transaction(function(tx) {
28     tx.executeSql(‘DELETE FROM LOGS WHERE id=?‘, [4],function (tx,results) {
29         console.log(‘success‘);
30     },function (tx,error) {
31         console.log(‘failed:‘+error.message);
32     });
33 });
34 //改：更新
35 db.transaction(function(tx) {
36     tx.executeSql(‘UPDATE LOGS SET log=\‘www.w3cschool.cc\‘ WHERE id=?‘, [2]);
37 });
38 
39 db.transaction(function (tx) {
40     //查
41     tx.executeSql(‘SELECT * FROM LOGS‘, [], function (tx, results) {
42         var len = results.rows.length, i;
43         msg = "<p>查询记录条数: " + len + "</p>";
44         // document.querySelector(‘#status‘).innerHTML +=  msg;
45         document.getElementById(‘status‘).innerHTML +=  msg;
46         for (i = 0; i < len; i++){
47             msg = "<p><b>" + results.rows.item(i).log + "</b></p>";
48             // document.querySelector(‘#status‘).innerHTML +=  msg;
49             document.getElementById(‘status‘).innerHTML +=  msg;
50         }
51     }, null);
52 });