Web Development
Learn Web Development From Scratch 0️⃣ HTML / CSS 1️⃣ JavaScript 2️⃣ React / Vue / Angular 3️⃣ Node.js / Express 4️⃣ REST API 5️⃣ SQL / NoSQL Databases 6️⃣ UI / UX Design 7️⃣ Git / GitHub Admin: @love_data
显示更多📈 Telegram 频道 Web Development 的分析概览
频道 Web Development (@webdevcoursefree) 英语 语言赛道中的 是活跃参与者。目前社区聚集了 78 405 名订阅者,在 技术与应用 类别中位列第 1 635,并在 印度 地区排名第 4 127 位。
📊 受众指标与增长动态
自 невідомо 创建以来,项目保持高速增长,吸引了 78 405 名订阅者。
根据 12 六月, 2026 的最新数据,频道保持稳定运转。过去 30 天订阅人数变化为 562,过去 24 小时变化为 4,整体触达仍然可观。
- 认证状态: 未认证
- 互动率 (ER): 平均受众互动率为 3.80%。内容发布后 24 小时内通常能获得 1.31% 的反应,占订阅者总量。
- 帖子覆盖: 每篇帖子平均可获得 2 981 次浏览,首日通常累积 1 027 次浏览。
- 互动与反馈: 受众积极参与,单帖平均反应数为 10。
- 主题关注点: 内容集中在 html, css, javascript, github, git 等核心主题上。
📝 描述与内容策略
作者将该频道定位为表达主观观点的平台:
“Learn Web Development From Scratch
0️⃣ HTML / CSS
1️⃣ JavaScript
2️⃣ React / Vue / Angular
3️⃣ Node.js / Express
4️⃣ REST API
5️⃣ SQL / NoSQL Databases
6️⃣ UI / UX Design
7️⃣ Git / GitHub
Admin: @love_data”
凭借高频更新(最新数据采集于 13 六月, 2026),频道始终保持新鲜度与高覆盖。分析显示受众积极互动,使其成为 技术与应用 类别中的关键影响点。
const express = require("express");
const app = express();
app.get("/", (req, res) => {
res.send("Hello Backend");
});
app.listen(3000, () => {
console.log("Server running on port 3000");
});
• Creates server, handles GET request, sends response, listens on port 3000
🔄 What is an API
• API = Application Programming Interface
• Frontend talks to backend using APIs, usually in JSON format
🧠 Common HTTP Methods (Backend)
• GET: Fetch data
• POST: Send data
• PUT: Update data
• DELETE: Remove data
⚠️ Common Beginner Mistakes
• Forgetting to install express
• Not using correct port
• Not sending response
• Confusing frontend and backend
🧪 Mini Practice Task
• Create basic Express server
• Create route /about
• Create route /api/user returning JSON
• Start server and test in browser
✅ Mini Practice Task – Solution 🌐
🟢 Step 1️⃣ Install Express
Open terminal inside project folder:
npm init -y
npm install express
✔ Creates package.json
✔ Installs Express framework
📄 Step 2️⃣ Create server.js
Create a file named server.js and add:
const express = require("express");
const app = express();
// Home route
app.get("/", (req, res) => {
res.send("Welcome to my server");
});
// About route
app.get("/about", (req, res) => {
res.send("This is About Page");
});
// API route returning JSON
app.get("/api/user", (req, res) => {
res.json({ name: "Deepak", role: "Developer", age: 25 });
});
// Start server
app.listen(3000, () => {
console.log("Server running on http://localhost:3000");
});
▶️ Step 3️⃣ Start the Server
Run in terminal:
node server.js
You should see: Server running on http://localhost:3000
🌍 Step 4️⃣ Test in Browser
Open these URLs:
• http://localhost:3000/ → Welcome message
• http://localhost:3000/about → About page text
• http://localhost:3000/api/user → JSON response
Double Tap ♥️ For Moreimport { useEffect } from "react";
useEffect(() => {
// code to run
}, []);
🚀 Run only once (on page load)
useEffect(() => {
console.log("Component mounted");
}, []);
👉 Empty dependency array → runs once.
🔄 Run when state changes
useEffect(() => {
console.log("Count changed");
}, [count]);
👉 Runs whenever count updates.
⏱️ Real Example — Timer
import { useState, useEffect } from "react";
function Timer() {
const [time, setTime] = useState(0);
useEffect(() => {
const interval = setInterval(() => {
setTime(t => t + 1);
}, 1000);
return () => clearInterval(interval);
}, []);
return <h2>{time}</h2>;
}
✔ Runs timer automatically
✔ Cleans memory using return
🎯 Hook 2: useRef (Access DOM / Store Values)
❓ What is useRef
useRef gives direct access to DOM elements. Also stores values without re-rendering.
Simple meaning 👉 Reference to element or value.
📌 Why useRef is used
• Focus input automatically
• Access DOM elements
• Store previous value
• Avoid re-render
✍️ Basic Syntax
import { useRef } from "react";
const inputRef = useRef();
🎯 Example — Focus input automatically
import { useRef } from "react";
function InputFocus() {
const inputRef = useRef();
const handleFocus = () => {
inputRef.current.focus();
};
return (
<div>
<input ref={inputRef} />
<button onClick={handleFocus}>Focus</button>
</div>
);
}
✔ Button click focuses input.
⚖️ useState, useEffect, and useRef — What's the difference?
• useState: Stores changing data that triggers re-renders.
• useEffect: Runs side effects (e.g., API calls, timers).
• useRef: Accesses DOM elements or stores values without re-rendering.
⚠️ Common Beginner Mistakes
• Forgetting dependency array in useEffect
• Infinite loops in useEffect
• Using useRef instead of state
• Not cleaning side effects
🧪 Mini Practice Task
• Print message when component loads using useEffect
• Create timer using useEffect
• Focus input automatically using useRef
• Store previous value using useRef
✅ Double Tap ♥️ For Moreimport { useState } from "react";
function App() {
const [items, setItems] = useState([]);
return <div></div>;
}
export default App;
✔ items → list data
✔ setItems() → update list
➕ Step 2: Create (Add Item)
Add new item to list.
const [input, setInput] = useState("");
const addItem = () => {
setItems([...items, input]);
setInput("");
};
UI
<input value={input} onChange={(e) => setInput(e.target.value)} />
<button onClick={addItem}>Add</button>
👀 Step 3: Read (Show Items)
Display list using map.
<ul>
{items.map((item, index) => (
<li key={index}>{item}</li>
))}
</ul>
❌ Step 4: Delete Item
Remove item from list.
const deleteItem = (index) => {
const newItems = items.filter((_, i) => i !== index);
setItems(newItems);
};
UI
<button onClick={() => deleteItem(index)}>Delete</button>
✏️ Step 5: Update Item (Edit)
Update existing data.
const updateItem = (index) => {
const newValue = prompt("Update item");
const updated = [...items];
updated[index] = newValue;
setItems(updated);
};
UI
<button onClick={() => updateItem(index)}>Edit</button>
✅ Complete CRUD UI Example
import { useState } from "react";
function App() {
const [items, setItems] = useState([]);
const [input, setInput] = useState("");
const addItem = () => {
if (!input) return;
setItems([...items, input]);
setInput("");
};
const deleteItem = (index) => {
setItems(items.filter((_, i) => i !== index));
};
const updateItem = (index) => {
const newValue = prompt("Update item");
if (!newValue) return;
const updated = [...items];
updated[index] = newValue;
setItems(updated);
};
return (
<div>
<h2>Todo CRUD</h2>
<input value={input} onChange={(e) => setInput(e.target.value)} />
<button onClick={addItem}>Add</button>
<ul>
{items.map((item, index) => (
<li key={index}>
{item}
<button onClick={() => updateItem(index)}>Edit</button>
<button onClick={() => deleteItem(index)}>Delete</button>
</li>
))}
</ul>
</div>
);
}
export default App;
🧠 How CRUD Works Internally
• User action → event triggers
• State updates
• React re-renders UI
This is React’s core workflow.
⚠️ Common Beginner Mistakes
• Mutating state directly
• Forgetting key in list
• Not copying arrays before update
• Confusing state updates
🧪 Mini Practice Task
• Build a simple student list CRUD
• Add student name
• Edit student name
• Delete student
• Show total count
✅ Double Tap ♥️ For More
现已上线!2025 年 Telegram 研究 — 年度关键洞察 
