Question

在这个例子中，我要通过提示询问用户他们的名字，然后使用cookie写入div，“Welcome，savedCookie！”进入之后，然后每次他们在到期前访问页面。

我让浏览器提示询问我的名字，然后它将div写为“欢迎，未定义！”我无法弄清楚为什么会收到错误。

//Setting cookie for Users Name
function set_it() {
    var userName = prompt("Please Enter Your Name", ""),
      thetext = "name=" + userName,
      expdate = ";expires=Mon, 27 Mar 2017 13:00:00 UTC",
      newtext = encodeURIComponent(thetext);
    newtext += expdate;
    document.cookie = newtext;
  }
  //Reading & Writing cookie

function read_it() {
  var rawCookie = document.cookie;
  bakedCookie = decodeURIComponent(rawCookie);
  yumCookie = bakedCookie.split("=");
  document.getElementById("greeting").innerHTML = "<p>Welcome, " + yumCookie[1] + "!</p>";

}

if (document.cookie) {
  read_it();
} else {
  set_it();
  read_it();
}

<!DOCTYPE html>
<html>

<head>
  <title>Page Title</title>
</head>

<body>
  <div id="greeting">
    <script src="prjs13_2.js"></script>
  </div>

</body>

</html>

Answer 1

尝试在控制台中运行您的唯一代码，看看你得到了什么 -

var userLocation;

function getUserLocation() {
  $.ajax({
    url: 'https://www.example.com/location.json',
    success: function(response) {
      userLocation = response.coordinates;
    }
  }).done(function() {
       getCurrentWeather()
  });
}

function getCurrentWeather() {
  $.ajax({
    url: 'https://www.example.com/weather' + userLocation +  '.json',
    success: function(response) {
      console.log(response);
    }
  });
}

我是为了这个名字＆＃34; david＆＃34;我得到了这个 -

name％3Ddavid; expires = Mon，2017年3月27日13:00:00 UTC＆＃34;

当您设置Cookie时，您的name属性无效。请尝试使用此代码（不使用encodeURIComponent和;而不是逗号） -

 var userName = prompt("Please Enter Your Name", ""),
      thetext = "name=" + userName,
      expdate = ";expires=Mon, 27 Mar 2017 13:00:00 UTC",
      newtext = encodeURIComponent(thetext);
    newtext += expdate;
    document.cookie = newtext;

Answer 2

您可以使用以下功能来获取/设置Cookie：

function setCookie(cname, cvalue, exdays) {
    var d = new Date();
    d.setTime(d.getTime() + (exdays*24*60*60*1000));
    var expires = "expires="+d.toUTCString();
    document.cookie = cname + "=" + cvalue + "; " + expires;
}

function getCookie(cname) {
    var name = cname + "=";
    var ca = document.cookie.split(';');
    for(var i = 0; i < ca.length; i++) {
        var c = ca[i];
        while (c.charAt(0) == ' ') {
            c = c.substring(1);
        }
        if (c.indexOf(name) == 0) {
            return c.substring(name.length, c.length);
        }
    }
    return "";
}

function checkCookie() {
    var user = getCookie("username");
    if (user != "") {
        alert("Welcome again " + user);
    } else {
        user = prompt("Please enter your name:", "");
        if (user != "" && user != null) {
            setCookie("username", user, 365);
        }
    }
}

以下是一些小提琴示例：fiddle

使用JavaScript设置，读取和编写Cookie

2 个答案: