我有一份清单,如下 const[users,setUsers]=useState([]); 要动态添加新用户并更新UI,我有一个函数,如下所示 const addNewUser = newUser => {
setUsers(previousUsers=>{
//only add user if he has not been added
let existingUser = previousUsers.find((x)=>x.id===newUser.id);
if(!existingUs
I m发送props值到输入句柄I m尝试编辑字段it is not editing..How to write onchange field.When function.Can任何人简要解释一下受控和非受控输入
handleUserInput = (e) => {
//what to do here in order to edit the input field
}
render() {
return(
<div>
<div className="info">
&l
目前,我只能通过微调按钮更改输入字段的值。
但是,当我在输入中单击以手动键入一个数字时,文本光标就消失了,我无法在里面输入。我可以在输入的同时点击输入框,这是可行的。下面是我的React代码的简化:
constructor(props) {
super(props)
this.state = {
quantity: 1
}
}
//This is just making some API call, but am I supposed to do anything else here to update the value?
handleQu
我一直在尝试使用ReactJS在window中更新基于按键的输入。我正在构建一个基本的计算器,它只有一个输入。我希望一旦按下某个键,输入就始终成为目标,并更新这些值。我还有另一个用于验证的函数,因此按键函数仍将通过验证函数传递。谢谢!
我有这样的东西:
window.onkeypress = function(e){
this.inputFocus(); //my custom function to position the cursor in the input
this.setState({display: this.state.display + e.key});
}