1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
|
---
abbrlink: 1126783921
categories:
- 往昔
date: "2025-07-04 10:46:53"
tags:
- 翻译
- JavaScript
title: 使用Javascript TSS和Highlights构建一个文本阅读器
---
> 原文：https://jsdev.space/tts-sentence-reader/
>
> 翻译：Verdant<i@glowisle.me>
在这篇文章中，我们将构建一个简单的Web工具来探究**Text-toSpeech(TTS)**在JavaScript中是如何工作的。我们也将深入研究**句子级高亮**的工作逻辑。这两项功能经常结合在一起使用，以走到浏览器中打造无障碍的动态阅读体验。
步骤:
1. 学习在浏览器中,TTS是如何工作的
2. 探究动态高亮句子的实现方法
3. 用HTML, CSS, JavaScript构建一个小工具([Demo & Code](https://codepen.io/jsdevspace/pen/YPXRRjO))
## 📢 浏览器中的TTS概述
JavaScript提供一个内置的API：[`SpeechSynthesis`](https://developer.mozilla.org/en-US/docs/Web/API/SpeechSynthesis)，它允许我们使用系统中的可用嗓音去大声朗读问文字。
### 核心对象:
- `speechSynthesis` — 控制播放、暂停、恢复、停止
- `SpeechSynthesisUtterance` — 作为TTS引擎的待播报文本
### ✨示例:
```js
const msg = new SpeechSynthesisUtterance("Hello, world!");
window.speechSynthesis.speak(msg);
```
### ⚙️ 添加嗓音和配置
```js
const utter = new SpeechSynthesisUtterance("This is a test");
const voices = window.speechSynthesis.getVoices();
utter.voice = voices.find(v => v.lang === 'en-US');
utter.rate = 1.2;
utter.pitch = 1;
window.speechSynthesis.speak(utter);
```
你也可以追踪朗读的开始和结束：
```js
utter.onstart = () => console.log('Started speaking');
utter.onend = () => console.log('Finished speaking');
```
## ✍️ 句子高亮
展示给用户哪一个句子正在阅读，我们需要用CSS和JavaScript来高亮文本。
### 示例 HTML:
```html
<p>
<span class="sentence">First sentence.</span>
<span class="sentence">Second sentence.</span>
</p>
```
### 处理高亮的CSS:
```css
.sentence.active {
background-color: yellow;
font-weight: bold;
}
```
### JavaScript高亮逻辑：
```js
function highlight(index) {
document.querySelectorAll('.sentence').forEach((el, i) => {
el.classList.toggle('active', i === index);
});
}
```
# 🚀项目: 使用TSS和高亮的阅读器
我们的程序将要：
- 逐句朗读文本
- 高亮朗读中的文本
- 提供播放、暂停、恢复、停止
- 让用户能选择嗓音
## 📄 HTML结构
```html
<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8" />
<meta name="viewport" content="width=device-width, initial-scale=1.0" />
<meta name="description" content="Build an interactive sentence-level text-to-speech reader with highlight, playback controls, and local progress tracking using HTML and JavaScript." />
<title>Interactive TTS Article Reader</title>
</head>
<body>
<h1>Read Along TTS Demo</h1>
<div class="toolbar">
<button id="start">Play</button>
<button id="pause" disabled>Pause</button>
<button id="resume" disabled>Resume</button>
<button id="stop" disabled>Stop</button>
<button id="reset">Reset</button>
<select id="voices"></select>
</div>
<div class="text-block" id="reader">
<span class="line">Learning to code is a never-ending journey.</span>
<span class="line">Technologies evolve rapidly, requiring constant adaptation.</span>
<span class="line">JavaScript, HTML, and CSS are essential tools for web development.</span>
<span class="line">Frameworks like React and Vue enhance front-end capabilities.</span>
<span class="line">Back-end skills with Node.js extend JavaScript to the server.</span>
</div>
<div class="progress">
<span id="progressText">0/0</span>
<div class="bar"><div class="bar-fill" id="bar"></div></div>
</div>
</body>
</html>
```
## 🎨 CSS 样式
```css
body {
font-family: sans-serif;
margin: 0;
padding: 2rem;
background: #f0f4f8;
color: #333;
}
h1 {
text-align: center;
margin-bottom: 2rem;
}
.toolbar {
display: flex;
justify-content: center;
flex-wrap: wrap;
gap: 1rem;
margin-bottom: 2rem;
}
.toolbar button,
.toolbar select {
padding: 0.6rem 1.2rem;
border-radius: 4px;
border: none;
font-size: 1rem;
}
.toolbar button {
background: #0077cc;
color: white;
cursor: pointer;
}
.toolbar button:disabled {
background: #ccc;
cursor: not-allowed;
}
.text-block {
background: white;
padding: 1.5rem;
border-radius: 6px;
box-shadow: 0 2px 6px rgba(0, 0, 0, 0.1);
}
.line {
display: block;
margin-bottom: 1rem;
cursor: pointer;
transition: background 0.3s;
}
.line:hover {
background: #f9f9f9;
}
.line.active {
background: #fff3cd;
font-weight: bold;
}
.progress {
text-align: center;
margin-top: 1rem;
}
.bar {
height: 8px;
width: 100%;
background: #eee;
border-radius: 4px;
overflow: hidden;
}
.bar-fill {
height: 100%;
width: 0;
background: linear-gradient(to right, #0077cc, #005fa3);
transition: width 0.3s;
}
```
## 💡 JavaScript逻辑
```js
const lines = document.querySelectorAll('.line');
const playBtn = document.getElementById('start');
const pauseBtn = document.getElementById('pause');
const resumeBtn = document.getElementById('resume');
const stopBtn = document.getElementById('stop');
const resetBtn = document.getElementById('reset');
const voiceSelect = document.getElementById('voices');
const progressText = document.getElementById('progressText');
const progressBar = document.getElementById('bar');
const synth = window.speechSynthesis;
let voices = [];
let currentIndex = 0;
let currentUtterance = null;
let isPaused = false;
function populateVoices() {
voices = synth.getVoices();
voiceSelect.innerHTML = '';
voices.forEach((voice, index) => {
const opt = document.createElement('option');
opt.value = index;
opt.textContent = `${voice.name} (${voice.lang})`;
voiceSelect.appendChild(opt);
});
}
synth.onvoiceschanged = populateVoices;
populateVoices();
function updateUI() {
progressText.textContent = `${currentIndex + 1}/${lines.length}`;
progressBar.style.width = `${((currentIndex + 1) / lines.length) * 100}%`;
}
function highlightLine(index) {
lines.forEach((line, i) => {
line.classList.toggle('active', i === index);
});
lines[index]?.scrollIntoView({ behavior: 'smooth', block: 'center' });
}
function speakLine(index) {
if (index >= lines.length) return;
const text = lines[index].textContent;
const utter = new SpeechSynthesisUtterance(text);
const selected = voiceSelect.value;
if (voices[selected]) utter.voice = voices[selected];
utter.rate = 1;
utter.onstart = () => {
highlightLine(index);
playBtn.disabled = true;
pauseBtn.disabled = false;
resumeBtn.disabled = true;
stopBtn.disabled = false;
};
utter.onend = () => {
if (!isPaused) {
currentIndex++;
if (currentIndex < lines.length) {
speakLine(currentIndex);
} else {
resetControls();
}
}
};
currentUtterance = utter;
synth.speak(utter);
updateUI();
}
function resetControls() {
playBtn.disabled = false;
pauseBtn.disabled = true;
resumeBtn.disabled = true;
stopBtn.disabled = true;
}
playBtn.onclick = () => {
currentIndex = 0;
speakLine(currentIndex);
};
pauseBtn.onclick = () => {
synth.pause();
isPaused = true;
pauseBtn.disabled = true;
resumeBtn.disabled = false;
};
resumeBtn.onclick = () => {
synth.resume();
isPaused = false;
pauseBtn.disabled = false;
resumeBtn.disabled = true;
};
stopBtn.onclick = () => {
synth.cancel();
resetControls();
};
resetBtn.onclick = () => {
synth.cancel();
currentIndex = 0;
highlightLine(currentIndex);
updateUI();
};
lines.forEach((line, index) => {
line.addEventListener('click', () => {
synth.cancel();
currentIndex = index;
speakLine(currentIndex);
});
});
updateUI();
```
## ✅ 它们如何工作
- 每一个句子都是`<span class="sentence">`
- 我们迭代句子并使用`SpeechSynthesisUtterance`大声朗读
- 在朗读过程中，高亮正确的文本并滚动
- 一个句子结束后，自动朗读下一个句子
## 🔚 尾声
阅读了本文，你理解了：
- 浏览器TTS的运行原理
- 如何实现动态高亮文本
- 如何从零构建一个功能齐全的阅读界面
你可以扩展项目功能：
- 在`localStorage`保存阅读进度
- 添加进度条
- 加载外部文章或用户输入
|
