TODOLIST Update in REACT



所以我试图更新我通过Addlist得到的值,我尝试了这个,但这不是工作。此外,当我单击"+"按钮而不写入任何内容时,将创建一个空列表。我该如何阻止它。我在下面附上了一个代码。

import React from "react";
import "./App.css";
import { useState } from "react";
import TodoList from "./components/TodoList";
function App() {
const [input, setInput] = useState("");
const [list, setList] = useState([]);

const updateList = (e) => {

setInput(e.target.value);

};
const AddList = () => {
console.log("value added")
setList((addValue) => {


return [...addValue, input];


});
setInput("");
};
const updateItems=(id)=>{
const newValue=[...list].map((newVal)=>{
if(input.id===id){
input.text='';
}
return newVal;
})
setList(newValue);

}
const deleteItems = (id) => {
console.log("deleted");
setList((addValue) => {
return addValue.filter((element, index) => {
return index !== id;
});
});
};
return (

<div className="todo-app">
<h1> Enter Anything</h1>
<input
type="text"
placeholder="Add anything"
value={input}
onChange={updateList}
/>
<button onClick={AddList}>+</button>
<ul>
{list.map((itemsvalue, id) => {
return (
<TodoList
itemsValue={itemsvalue}
key={id}
onSelect={deleteItems}
id={id}
onUpdate={updateItems}
/>
);
})}
</ul>
</div>
);
}
export default App;

任何形式的帮助将不胜感激。另外,如果我想把它分成多个组件,有没有办法呢?

当用户单击add按钮时,会检查是否为空字符串AddList方法例如:-用户更新第二个索引值,第二个位置值将被更新。

const [input, setInput] = useState('');
const [list, setList] = useState([]);
const [index, setIndex] = useState(null);
const updateList = (e) => {
setInput(e.target.value);
};
useEffect(() => {
setList(list);
console.log(list, '<>?');
}, [index]);
const AddList = () => {
if (input.trim() !== '') {
setList([...list, input]);
}
setInput('');
};
const updateValue = (index) => {
console.log(list[index]);
setIndex(index);
if (list[index].trim() !== '') {
setInput(list[index]);
}
};
const UpdateList = () => {
list[index] = input;
console.log(list, 'before  <>?');
setIndex(null);
setInput('');
};
return (
<div>
<input type="text" placeholder="Add anything" value={input} onChange={updateList} />
<button disabled={!index && !list.length === 0} onClick={AddList}>
Add
</button>
<button disabled={input.trim() === ''} onClick={UpdateList}>
Update
</button>
{list.map((m, index) => (
<h1 style={{ border: '1px solid black' }} onClick={() => updateValue(index)}>
{m}
</h1>
))}
</div>
);

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