JSON

1.字符串转换成json对象

var txt = '{"employees":[' +
'{"firstName":"Bill","lastName":"Gates" },' +
'{"firstName":"George","lastName":"Bush" },' +
'{"firstName":"Thomas","lastName":"Carter" }]}';
方法①.var obj = eval ("(" + txt + ")");
方法②.var obj = JSON.parse(txt);---更安全
访问：document.getElementById("fname").innerHTML=obj.employees[1].firstName