


React makes mobile phone data synchronization and display in the interface function
This time I will bring you the function of react to synchronize the display of mobile phone data on the interface. What are the precautions for react to synchronize the display of mobile phone data on the interface? The following is a practical case, let's take a look. . Requirements are as follows
- The length of the input content in the input box is greater than 0, and the preview information is displayed
- Leave the cursor and close the preview information
- Insert a
- special character
_ every 4 digits in the preview information, and the input content remains unchanged
The limit length is 13 Bit - Only allows the input of numbers (0-9)
-
// Zinput.js import React, { Component } from 'react'; import './Zinput.css' // NOTE: 获取焦点事件 原生onFocus 即可 // NOTE: 离开焦点事件 原生onBlur即可 // NOTE: 输入框数据过滤 直接在change方法里进行过滤 // NOTE: 条件处理 通过不同条件返回不同节点做条件处理 class Zinput extends Component { constructor(props) { super(props); this.state = { value: '', showBig: false, }; this.handleChange = this.handleChange.bind(this); this.inputOnFocus = this.inputOnFocus.bind(this); this.inputOnBlur = this.inputOnBlur.bind(this); } inputOnFocus() { if (this.state.value.length > 0) { this.setState({ showBig: true }) } } inputOnBlur() { this.setState({ showBig: false }) if(this.props.chanegNumber){ this.props.chanegNumber(this.state.value) } } handleChange(event) { let val = event.target.value.substr(0, 13) .replace(/[^\d]/g, '') event.target.value = val this.setState({ value: val, showBig: true, }); } /** * 根据字符串没隔len位插入一个下滑杠,返回处理后的字符串 * @method getStr * @author 朱阳星 * @datetime 2018-04-02T09:57:58+080 * @email zhuyangxing@foxmail.com * @param {String} str 待处理字符串 * @param {Number} len 每隔位数插入下滑杠 * @return {String} 处理后的字符串 */ getStr(str, len) { let lenth = str.length let len1 = len - 1 let newStr = '' for (var i = 0; i 0) { newStr += str.charAt(i) + '_' } else { newStr += str.charAt(i) } } if (newStr.length % (len + 1) === 0) { // 解决最后一位为补充项问题 newStr = newStr.substr(0, newStr.length - 1) } return newStr } render() { // NOTE return 需要用圆括号包住并处理 // NOTE 条件语句里没有节点也要用空字符串进行处理 否则sonalint会报错,页面也会报错 const showBig = this.state.showBig ? ( <p>{ this.getStr(this.state.value,4) }</p> ) : '' return ( <p> <input> {showBig} </p> ) } } export default Zinput; // Don't forget to use export default!
<!-- Zinput.css --> .zInput{ position: absolute; top:80px; left:40px; } .input { position: absolute; top: 0; left: 0; } .big-show { position: relative; top: -40px; font-size: 36px; line-height: 40px; background-color: red; }
Although the function is implemented, it must be a sub-component of a certain node There are two ways to call the parent component
1. Use refs to directly obtain the value of the child component state
constructor(props) { super(props); this.handerClick2 = this.handerClick2.bind(this); } handerClick2(){ // NOTE 父组件通过refs获取子组件的state console.log("使用ref获取子组件的值",this.refs.zinput.state.value) } render() { return ( <p> <zinput></zinput> <input> </p> ); }
2. Call the method passed by the parent component every time the focus of the child component leaves. , modify the state value of the parent component
constructor(props) { super(props); this.state = { phoneNumber: '', }; this.handerClick = this.handerClick.bind(this); this.changePhoneNumber = this.changePhoneNumber.bind(this); } changePhoneNumber(number){ this.setState({ phoneNumber: number, }) } handerClick(){ // NOTE 根据react的思想是在子组件处理完某件事的时候调用父组件的方法修改父组件的state值 console.log("使用state获取值",this.state.phoneNumber) } render() { return ( <p> <zinput></zinput> <input> </p> ); }
I believe you have mastered the method after reading the case in this article. For more exciting information, please pay attention to other related articles on the PHP Chinese website!
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Add loading during lazy loading processbabel conversion es6 method implementationThe above is the detailed content of React makes mobile phone data synchronization and display in the interface function. For more information, please follow other related articles on the PHP Chinese website!

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