我该如何解决“未捕获的SyntaxError：JSON位置0上的意外令牌l…？”

Question

I am testing pulling in API weather data (open weather map.org) with JavaScript and XMLHttpRequest. 我正在测试使用JavaScript和XMLHttpRequest提取API天气数据（open weather map.org）。 I am using Github pages as my test site. 我正在使用Github页面作为测试站点。 I need JSON.parse to turn the info. 我需要JSON.parse来打开信息。 into a JS object, but JSON.parse is always an issue. 放入JS对象，但JSON.parse始终是一个问题。 I have been struggling with this error message: 我一直在努力与此错误消息：

Uncaught SyntaxError: Unexpected token l in JSON at position 0
at JSON.parse (<anonymous>)
at data.weather.forEach.weather (scripts.js:29)
at Array.forEach (<anonymous>)
at XMLHttpRequest.request.onload (scripts.js:22)

I read on several support threads that it was a server side error and to look in the network tab -- I did and everything has a 200 status!? 我在几个支持线程上看到这是服务器端错误，然后在“网络”选项卡中查找-我确实做了，并且所有状态都为200！ I also read on multiple threads that it meant that JSON was not being returned. 我还在多个线程上读到，这意味着未返回JSON。 But either there is no mention of how to remedy this or I have no clue what they are talking about. 但是，要么没有提及如何解决这个问题，要么我不知道他们在说什么。 I am new to this and have been stuck with error messages for weeks. 我对此并不陌生，并在数周内一直被错误消息所困扰。 I am the only developer at my startup and need to solve this soon. 我是启动时唯一的开发人员，需要尽快解决。 Any guidance would be greatly appreciated. 任何指导将不胜感激。

scripts.js: scripts.js中：

// Whole-script strict mode syntax
'use strict';
const app = document.getElementById("root");

const logo = document.createElement("img");
logo.src = "logo.png";

const container = document.createElement("div");
container.setAttribute("class", "container");

app.appendChild(logo);
app.appendChild(container);

var request = new XMLHttpRequest();
request.open("GET", "https://api.openweathermap.org/data/2.5/weather? 
    q = London & APPID = 3190 b3e074868b6189a94a8795afa8a2 ", true);
    request.onload = function() {

      // Begin accessing JSON data here
      'use strict';
      var data = JSON.parse(this.response);
      if (request.status >= 200 && request.status < 400) {
        data.weather.forEach(weather => {
          const card = document.createElement("div");
          card.setAttribute("class", "card");
          const h1 = document.createElement("h1");
          h1.textContent = weather.title;

          const p = document.createElement("p");
          weather.description = JSON.parse(weather.description).substring(0, 300);
          p.textContent = `${weather.description}...`;

          container.appendChild(card);
          card.appendChild(h1);
          card.appendChild(p);
        });
      } else {
        const errorMessage = document.createElement("marquee");
        errorMessage.textContent = `Hug it, it's not working!`;
        app.appendChild(errorMessage);
      }
    }

    request.send();

index.html: index.html的：

<!DOCTYPE html>
<html lang="en">

<head>
  <meta charset="utf-8">
  <meta name="viewport" content="width=device-width, initial-scale=1.0">

  <title>You are Techy Job Listings</title>

  <link href="https://fonts.googleapis.com/css?family=Dosis:400,700" 
   rel="stylesheet">
  <link href="style.css" rel="stylesheet">



</head>

<body>

style.css: style.css中：

* {
  box-sizing: border-box
}

html {
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
  font-family: 'Dosis', sans-serif;
  line-height: 1.6;
  color: #666;
  background: #F6F6F6;
}

#root {
  max-width: 1200px;
  margin: 0 auto;
}

h1 {
  text-align: center;
  padding: 1.5rem 2.5rem;
  background-image: linear-gradient(120deg, #fbc2eb 0%, #a6c1ee 100%);
  margin: 0 0 2rem 0;
  font-size: 1.5rem;
  color: white;
}

p {
  padding: 0 2.5rem 2.5rem;
  margin: 0;
}

.container {
  display: flex;
  flex-wrap: wrap;
}

.card {
  margin: 1rem;
  background: white;
  box-shadow: 2px 4px 25px rgba(0, 0, 0, .1);
  border-radius: 12px;
  overflow: hidden;
  transition: all .2s linear;
}

.card:hover {
  box-shadow: 2px 8px 45px rgba(0, 0, 0, .15);
  transform: translate3D(0, -2px, 0);
}

@media screen and (min-width: 600px) {
  .card {
    flex: 1 1 calc(50% - 2rem);
  }
}

@media screen and (min-width: 900px) {
  .card {
    flex: 1 1 calc(33% - 2rem);
  }
}

.card:nth-child(2n) h1 {
  background-image: linear-gradient(120deg, #84fab0 0%, #8fd3f4 100%);
}

.card:nth-child(4n) h1 {
  background-image: linear-gradient(120deg, #ff9a9e 0%, #fecfef 100%);
}

.card:nth-child(5n) h1 {
  background-image: linear-gradient(120deg, #ffc3a0 0%, #ffafbd 100%);
}

Answer 1

weather.description is just an ordinary string, it's not JSON. weather.description只是一个普通的字符串，不是JSON。 So just take the substring of that. 因此，只需取其子字符串即可。

weather.description = weather.description.substring(0, 300);

我该如何解决“未捕获的SyntaxError：JSON位置0上的意外令牌l…？”

问题描述

1 个解决方案

解决方案1
0 2018-12-06 17:34:21

我该如何解决“未捕获的SyntaxError：JSON位置0上的意外令牌l…？”

问题描述

1 个解决方案

解决方案1 0 2018-12-06 17:34:21

解决方案1
0 2018-12-06 17:34:21