javascript 'Uncaught SyntaxError: Unexpected token u' 使用 JSON.parse 时
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'Uncaught SyntaxError: Unexpected token u' when using JSON.parse
提问by Juvi
I'm using JSON.parse as a simple database on my computer with LocalStorage. It works smoothly until I'm doing the check of this "database"; heres the code for entering information to LocalStorage:
我使用 JSON.parse 作为我计算机上带有 LocalStorage 的简单数据库。它运行顺利，直到我检查这个“数据库”；下面是将信息输入到 LocalStorage 的代码：
var users = JSON.parse(localStorage.registeredUsers);
users.push({username:name, password:userpass, connected:false});
localStorage.registeredUsers = JSON.stringify(users);
and when I', having the check of that registeredusers I get the error "Uncaught SyntaxError: Unexpected token u":
当我检查注册用户时，我收到错误“Uncaught SyntaxError: Unexpected token u”：
var users = JSON.parse(localStorage.registeredUsers);
if(users[userindex].connected)
{.........}
The error points to the line with JSON.parse. I tried to figure it out with some similiar topics but couldnt find the way.
错误指向带有 JSON.parse 的那一行。我试图用一些类似的主题来解决它，但找不到方法。
The code that I push into the array of localstorage:
我推入 localstorage 数组的代码：
function regBtn(event)
{
event.preventDefault();
name=document.forms["regform"]["username"].value;
userpass=document.forms["regform"]["password"].value;
localStorage.username=name;
localStorage.password=userpass;
if(!(localStorage.registeredUsers))
{
localStorage.registeredUsers = '[]';
}
var users = JSON.parse(localStorage.registeredUsers);
users.push({username:name, password:userpass, connected:false});
localStorage.registeredUsers = JSON.stringify(users);
$('#mainContent').load('HomePage.html');
}
采纳答案by Charlie Affumigato
Try
尝试
var users = localStorage.registeredUsers? JSON.parse(localStorage.registeredUsers) : [];
or if you don't like the ternary operator,
或者如果你不喜欢三元运算符，
var users=[];
if(localStorage.registeredUsers){
users=JSON.parse(localStorage.registeredUsers);
}
might help
可能有帮助
回答by bikshu
function setCookies(){
var cookiesObjects = {};
cookiesObjects.name = document.getElementById('usr').value;
cookiesObjects.email = document.getElementById('email').value;
cookiesObjects.age = document.getElementById('age').value;
var actualString = JSON.stringify(cookiesObjects);
document.cookie = "user="+ actualString;
}
function getCookies(){
var nameValueArray = document.cookie.split("=");
var cookieObject = JSON.parse(nameValueArray[1]);
document.getElementById('usr').value=cookieObject.name;
document.getElementById('email').value=cookieObject.email;
document.getElementById('age').value=cookieObject.age;
}
function clearCookies(){
document.getElementById('usr').value= "";
document.getElementById('email').value= "";
document.getElementById('age').value= "";
}
and saying Error : Uncaught SyntaxError: Unexpected token u
I can't identify the error's cause.
我无法确定错误的原因。
