或者用更简单命令: npm i -g create-react-app 2、开始动手创建吧!...接下来,我们来按照以下几个步骤来创建我们的第一个 React 项目: 1、在控制台输入以下命令进行项目创建: create-react-app my-first-react-app 2、将工作台环境切换至当前目录...,我们这里通过从 react 类库包引入 React、Component 模块...
1.创建自定义CKTextInput.js 组件类 1import React,{Component} from 'react';2import {3View,4TextInput,5StyleSheet,6Text7} from 'react-native';89exportdefaultclass CKTextInput extends Component{10constructor(){11super();12this.state={13inputValue:''14}15}1617render(){18return(19<View>20<TextI...
describe('Input', () => { it('render correctly Input component', () => { const InputComponent = renderer.create(<Input />).toJSON(); expect(InputComponent).toMatchSnapshot(); }); } 步骤2.当你首次运行这个 test 的时候,在测试过程中, 会生成一个__snapshots__的文件夹,里面的文件就是...
当input的值被初始化为undefined,但后来又变更为一个不同的值时,会产生"A component is changing an uncontrolled input to be controlled"警告。为了解决该问题,将input的值初始化为空字符串。比如说,value={message || ''}。 这里有个例子来展示错误是如何发生的。 import{useState}from'react';constApp= ()...
下面介绍下 input 组件的封装,其他组件也是类似封装 看下效果图: image.png 组件代码: 'use strict';import React,{Component}from'react';import{View,Text,Image,StyleSheet,TextInput,TouchableOpacity,}from'react-native';importBaseStylefrom'../constants/Style';importPropTypesfrom'prop-types';/** ...
optionText Optional string | Function | Component undefined | record Representation Field name of record to display in the suggestion item or function using the choice object as argument optionValue Optional string id Field name of record containing the value to use as input value resettable Optional...
保存input数据 class Login extends React.Component{ //初始化状态 state = { username:'', //用户名 password:'' //密码 } //保存表单数据到状态中 saveFormData = (dataType,event)=>{ this.setState({[dataType]:event.target.value}) }
// 修改后的ant表单组件import{Form,Select,Input,Button}from'antd';importSelectFormfrom'./selectForm';constFormItem=Form.Item;classAppextendsReact.Component{handleSubmit=(e)=>{e.preventDefault();this.props.form.validateFields((err,values)=>{if(!err){console.log('Received values of form: ',valu...
By default, it's a generic DOM<input/>component. Any custom input component implementation must useReact.forwardRef()to "forward"refto the underlying "core"<input/>component. Receives properties: value: string onChange(event: Event) Any other properties that were passed to<PhoneInput/>and aren...
<input type="submit" value="Submit" /> </form> ); } } 2.1 非受控组件 刚说到受控组件所有的状态都由外界接管,非受控组件则恰恰相反,它将状态存储在自身内部,我们可以借用 React 中的 ref 来访问它。同样还是官方的例子: class NameForm extends React.Component { ...