Todo list in react js

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This simple Todo List app is a great starting point for beginners to get familiar with React's fundamentals, including state management, event handling, and rendering lists.

Step-by-Step Guide to Creating a Todo List App in React

Step 1: Set Up Your React Environment

Before you start, make sure you have Node.js and npm (or yarn) installed on your machine. You can create a new React project using Create React App.

Open your terminal or command prompt and run the following command to create a new React project:

npx create-react-app todo-list

Navigate to the project directory:

cd todo-list

Step 2: Modify src/App.js

Replace the contents of src/App.js with the following code:

import React, { useState } from 'react';
import './App.css';

function App() {
  const [todos, setTodos] = useState([]);
  const [input, setInput] = useState('');

  const handleInputChange = (e) => {
    setInput(e.target.value);
  };

  const handleAddTodo = () => {
    if (input.trim()) {
      setTodos([...todos, { text: input, completed: false }]);
      setInput('');
    }
  };

  const handleToggleComplete = (index) => {
    const newTodos = todos.map((todo, i) => {
      if (i === index) {
        return { ...todo, completed: !todo.completed };
      }
      return todo;
    });
    setTodos(newTodos);
  };

  const handleDeleteTodo = (index) => {
    const newTodos = todos.filter((_, i) => i !== index);
    setTodos(newTodos);
  };

  return (
    <div className="App">
      <header className="App-header">
        <h1>Todo List</h1>
        <div>
          <input
            type="text"
            value={input}
            onChange={handleInputChange}
            placeholder="Add a new todo"
          />
          <button onClick={handleAddTodo}>Add</button>
        </div>
        <ul>
          {todos.map((todo, index) => (
            <li key={index}>
              <span
                style={{
                  textDecoration: todo.completed ? 'line-through' : 'none',
                }}
                onClick={() => handleToggleComplete(index)}
              >
                {todo.text}
              </span>
              <button onClick={() => handleDeleteTodo(index)}>Delete</button>
            </li>
          ))}
        </ul>
      </header>
    </div>
  );
}

export default App;

Step 3: Add Some Basic Styling

Modify the src/App.css file to add some basic styling:

.App {
  text-align: center;
}

.App-header {
  background-color: #282c34;
  min-height: 100vh;
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  font-size: calc(10px + 2vmin);
  color: white;
}

input {
  padding: 10px;
  margin-right: 10px;
  font-size: 16px;
}

button {
  padding: 10px;
  font-size: 16px;
  cursor: pointer;
}

ul {
  list-style-type: none;
  padding: 0;
}

li {
  display: flex;
  justify-content: space-between;
  align-items: center;
  padding: 10px;
  margin: 10px 0;
  background-color: #444;
  border-radius: 5px;
}

li span {
  cursor: pointer;
}

Step 4: Run the App

Now, you can run your Todo List app with the following command:

npm start

This command starts the development server and opens your new React application in your default web browser.

Happy Coding !

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