create a todo application in typescript

To create a todo application in TypeScript, we will be using React, Redux, and Node.js. Follow these steps:

1. Set up your project

   • Initialize your project with npm init
   • Install the necessary dependencies with npm install react react-dom redux react-redux redux-thunk node-sass
   • Set up your TypeScript configuration file (tsconfig.json) to include React and Node.

2. Create the Redux store

   • Create a store folder with an index.ts file inside.
   • In the index.ts file, import createStore from Redux and create a simple reducer function.

   index.ts
   import { createStore } from "redux";
   
   const initialState = { todos: [] };
   
   const reducer = (state = initialState, action: any) => {
     switch (action.type) {
       case "ADD_TODO":
         return { todos: [...state.todos, action.payload] };
       default:
         return state;
     }
   };
   
   const store = createStore(reducer);
   
   export default store;
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3. Create the Todo component

   • Create a components folder with a Todo.tsx file inside.
   • In the Todo.tsx file, create a functional component that takes a text prop and displays it.

   index.ts
   import React from "react";
   
   interface TodoProps {
     text: string;
   }
   
   const Todo: React.FC<TodoProps> = ({ text }: TodoProps) => {
     return <div>{text}</div>;
   };
   
   export default Todo;
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4. Create the TodoList component

   • Create a components folder with a TodoList.tsx file inside.
   • In the TodoList.tsx file, create a functional component that maps through a todos prop and displays each todo using the Todo component.

   index.ts
   import React from "react";
   import Todo from "./Todo";
   
   interface TodoListProps {
     todos: string[];
   }
   
   const TodoList: React.FC<TodoListProps> = ({ todos }: TodoListProps) => {
     return (
       <div>
         {todos.map((todo) => (
           <Todo text={todo} key={todo} />
         ))}
       </div>
     );
   };
   
   export default TodoList;
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5. Create the AddTodo component

   • Create a components folder with an AddTodo.tsx file inside.
   • In the AddTodo.tsx file, create a class component that takes user input and dispatches an action to add the new todo to the Redux store.

   index.ts
   import React, { Component } from "react";
   import { connect } from "react-redux";
   
   interface AddTodoProps {
     addTodo: (text: string) => void;
   }
   
   interface AddTodoState {
     text: string;
   }
   
   class AddTodo extends Component<AddTodoProps, AddTodoState> {
     state = {
       text: "",
     };
   
     handleChange = (e: React.ChangeEvent<HTMLInputElement>) => {
       this.setState({
         text: e.target.value,
       });
     };
   
     handleSubmit = (e: React.FormEvent<HTMLFormElement>) => {
       e.preventDefault();
       this.props.addTodo(this.state.text);
       this.setState({ text: "" });
     };
   
     render() {
       return (
         <form onSubmit={this.handleSubmit}>
           <input
             type="text"
             placeholder="Add a todo. . ."
             value={this.state.text}
             onChange={this.handleChange}
           />
           <button type="submit">Add Todo</button>
         </form>
       );
     }
   }
   
   const mapDispatchToProps = (dispatch: any) => ({
     addTodo: (text: string) => dispatch({ type: "ADD_TODO", payload: text }),
   });
   
   export default connect(null, mapDispatchToProps)(AddTodo);
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6. Create the App component

   • Create an App.tsx file that imports the TodoList and AddTodo components and renders them.

   index.ts
   import React from "react";
   import TodoList from "./components/TodoList";
   import AddTodo from "./components/AddTodo";
   
   const App: React.FC = () => {
     return (
       <div>
         <AddTodo />
         <TodoList todos={["todo1", "todo2", "todo3"]} />
       </div>
     );
   };
   
   export default App;
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7. Render the App

   • In the index.tsx file, import the React and ReactDOM libraries, the App component, and the Redux store.
   • Wrap the App component in a Provider component that takes the Redux store as a prop.
   • Use the ReactDOM.render() method to render the Provider component to the DOM.

   index.ts
   import React from "react";
   import ReactDOM from "react-dom";
   import { Provider } from "react-redux";
   import store from "./store";
   import App from "./App";
   
   ReactDOM.render(
     <Provider store={store}>
       <App />
     </Provider>,
     document.getElementById("root")
   );
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You now have a simple todo application with Redux state management in TypeScript!