我是ReactJs的新手，我在这里附加相同的代码。我有3个组成部分，分别是地址，电话和电子邮件。带地址的表单是父组件。电话和电子邮件是表单的子组件，我无法从父组件访问电话和电子邮件的状态对象，我知道如何将父状态对象发送给子组件，但是相反，我不知道它，我尝试了回调等等，但这没有帮助。请提供您的输入。
import React, { Component } from 'react';
import PropTypes from 'prop-types';
import {
Panel,
Button,
Col,
PageHeader,
ControlLabel,
FormControl,
HelpBlock,
FormGroup,
Checkbox,
Form,
Radio,
InputGroup,
Glyphicon } from 'react-bootstrap';
import FormControlFeedback from 'react-bootstrap/lib/FormControlFeedback';
import FormControlStatic from 'react-bootstrap/lib/FormControlStatic';
import InputGroupAddon from 'react-bootstrap/lib/InputGroupAddon';
import Email from './Email';
import Phone from './Phone';
const spacing = {
marginRight: "20px",
marginbottom: "20px"
}
const buttonalignment = {
marginLeft: "81px",
marginbottom: "20px"
}
class displayForms extends React.Component {
constructor(props) {
super(props);
// this.state.products = [];
this.state = {};
this.state.filterText = "";
this.state.products = [
{
id: 1,
Field1: "",
Field2: '',
Field3: '',
Field4: '',
Field5:'',
Field6: '',
Field7: ''
}
];
}
handleUserInput(filterText) {
this.setState({filterText: filterText});
};
handleRowDel(product) {
var index = this.state.products.indexOf(product);
this.state.products.splice(index, 1);
this.setState(this.state.products);
};
handleAddEvent(evt) {
var id = (+ new Date() + Math.floor(Math.random() * 999999)).toString(36);
var product = {
id: id,
Field1: "",
Field2: '',
Field13: '',
Field14: '',
Field5:'',
Field6: '',
Field7: ''
}
this.state.products.push(product);
this.setState(this.state.products);
}
handleProductTable(evt) {
var item = {
id: evt.target.id,
name: evt.target.name,
value: evt.target.value
};
console.log('item.value[0] in address',item.value);
console.log('item.value[1] in address',item.value);
console.log('item.value[2] in address',item.value);
var products = this.state.products.slice();
var newProducts = products.map(function(product) {
for (var key in product) {
if (key == item.name && product.id == item.id) {
product[key] = item.value;
}
}
return product;
});
this.setState({products:newProducts});
// console.log(this.state.products);
};
render() {
return (
<div>
<ProductTable onProductTableUpdate={this.handleProductTable.bind(this)} onRowAdd={this.handleAddEvent.bind(this)} onRowDel={this.handleRowDel.bind(this)} products={this.state.products} filterText={this.state.filterText}/>
<Email />
<Phone />
</div>
);
}
}
class ProductTable extends React.Component {
handleSubmit(event) {
event.preventDefault();
//myFunction();
console.log('In Handle submit function');
console.log('Addresses[0]:after get', this.props.products[0].Field1);
console.log('Addresses[0]:after get', this.props.products[0].Field2);
console.log('Addresses[0]:after get', this.props.products[0].Field3);
console.log('Addresses[0]:after get', this.props.products[0].Field4);
const form = event.target;
const data = new FormData(form);
const arrayValue = [];
var i = 0;
console.log('Data from Form:', data);
for (let name of data.keys()) {
const input = form.elements[name];
const parsedValue = data.get(name);
console.log('name', name);
console.log('parsedValue', parsedValue);
if (typeof (parsedValue) == 'undefined' || parsedValue == null) {
console.log('Not Defined or Not Null')
arrayValue[i] = "";
data.set(name, "");
}
else {
data.set(name, parsedValue);
arrayValue[i] = parsedValue;
}
i = i + 1;
}
console.log('arrayValue[4]:after get', arrayValue[4]);
console.log('arrayValue[1]:after get', arrayValue[1]);
console.log('arrayValue[3]:after get', arrayValue[3]);
//console.log('Addresses[0]:after get', this.props.products[0]);
}
render() {
var onProductTableUpdate = this.props.onProductTableUpdate;
var rowDel = this.props.onRowDel;
var filterText = this.props.filterText;
var product = this.props.products.map(function(product) {
if (product.Address_Line.indexOf(filterText) === -1) {
return;
}
return (<ProductRow onProductTableUpdate={onProductTableUpdate} product={product} onDelEvent={rowDel.bind(this)} key={product.id}/>)
});
return (
<div id="test">
<div className="row">
<div className="col-lg-12">
<PageHeader>Test App</PageHeader>
</div>
</div>
<form onSubmit={this.handleSubmit}>
<table>
<tr>
<td>
<FormGroup style={spacing}>
<ControlLabel>ID</ControlLabel>
<FormControl
id="field1" name="field1"
type="text"
placeholder="Enter Text"
/>
</FormGroup>
</td>
</tr>
<tr>
<td>
<FormGroup style={spacing}>
<ControlLabel> Month</ControlLabel>
<FormControl componentClass="select" id="MM" name="MM" placeholder="select">
<option value="01">01</option>
<option value="02">02</option>
<option value="03">03</option>
<option value="04">04</option>
<option value="05">05</option>
<option value="06">06</option>
<option value="07">07</option>
<option value="08">08</option>
<option value="09">09</option>
<option value="10">10</option>
<option value="11">11</option>
<option value="12">12</option>
</FormControl>
</FormGroup>
</td>
<td>
<FormGroup style={spacing}>
<ControlLabel> Day</ControlLabel>
<FormControl componentClass="select" id="DD" name="DD" placeholder="select">
<option value="01">01</option>
<option value="02">02</option>
<option value="03">03</option>
<option value="04">04</option>
<option value="05">05</option>
<option value="06">06</option>
<option value="07">07</option>
<option value="08">08</option>
<option value="09">09</option>
<option value="10">10</option>
<option value="11">11</option>
<option value="12">12</option>
<option value="13">13</option>
<option value="14">14</option>
<option value="15">15</option>
<option value="16">16</option>
<option value="17">17</option>
<option value="18">18</option>
<option value="19">19</option>
<option value="20">20</option>
<option value="21">21</option>
<option value="22">22</option>
<option value="23">23</option>
<option value="24">24</option>
<option value="25">25</option>
<option value="26">26</option>
<option value="27">27</option>
<option value="28">28</option>
<option value="29">29</option>
<option value="30">30</option>
<option value="31">31</option>
</FormControl>
</FormGroup>
</td>
</table>
</form>
<div className="col-lg-15">
<th>Address</th>
<button type="button" onClick={this.props.onRowAdd} className="btn btn-success pull-right">+</button>
<table className="table table-bordered">
<thead>
<tr>
<th>Field1</th>
<th>Field2</th>
<th>Field3</th>
<th>field4</th>
<th>field5</th>
<th>field6</th>
<th>field7</th>
</tr>
</thead>
<tbody>
{product}
</tbody>
</table>
</div>
</div>
);
}
}
class ProductRow extends React.Component {
onDelEvent() {
this.props.onDelEvent(this.props.product);
}
render() {
return (
<tr className="eachRow">
<EditableCell onProductTableUpdate={this.props.onProductTableUpdate} cellData={{
"type": "Field1",
value: this.props.product.Field1,
id: this.props.product.id
}}/>
<EditableCell onProductTableUpdate={this.props.onProductTableUpdate} cellData={{
type: "Field2",
value: this.props.product.Field2,
id: this.props.product.id
}}/>
<EditableCell onProductTableUpdate={this.props.onProductTableUpdate} cellData={{
type: "Field3",
value: this.props.product.Field3,
id: this.props.product.id
}}/>
<EditableCell onProductTableUpdate={this.props.onProductTableUpdate} cellData={{
type: "Field4",
value: this.props.product.Field4,
id: this.props.product.id
}}/>
<EditableCell onProductTableUpdate={this.props.onProductTableUpdate} cellData={{
type: "Field5",
value: this.props.product.Field5,
id: this.props.product.id
}}/>
<EditableCell onProductTableUpdate={this.props.onProductTableUpdate} cellData={{
type: "Field6",
value: this.props.product.Field6,
id: this.props.product.id
}}/>
<EditableCell onProductTableUpdate={this.props.onProductTableUpdate} cellData={{
type: "Field7",
value: this.props.product.Field7,
id: this.props.product.id
}}/>
<td className="del-cell">
<input type="button" onClick={this.onDelEvent.bind(this)} value="REMOVE" className="del-btn"/>
</td>
</tr>
);
}
}
class EditableCell extends React.Component {
render() {
return (
<td>
<input type='text' name={this.props.cellData.type} id={this.props.cellData.id} value={this.props.cellData.value} onChange={this.props.onProductTableUpdate}/>
</td>
);
}
}
displayForms.contextTypes = { setTitle: PropTypes.func.isRequired };
export default displayForms;
//import React, { PropTypes , Component } from 'react';
import React, { Component } from 'react';
import PropTypes from 'prop-types';
import {
Panel,
Button,
Col,
PageHeader,
ControlLabel,
FormControl,
HelpBlock,
FormGroup,
Checkbox,
Form,
Radio,
InputGroup,
Glyphicon } from 'react-bootstrap';
import FormControlFeedback from 'react-bootstrap/lib/FormControlFeedback';
import FormControlStatic from 'react-bootstrap/lib/FormControlStatic';
import InputGroupAddon from 'react-bootstrap/lib/InputGroupAddon';
class Phone extends React.Component {
constructor(props) {
super(props);
// this.state.phones = [];
this.state = {};
this.state.filterText = "";
this.state.phones = [
{
id: 1,
Field1: '',
Field2: '',
Field3: '',
Field4: '',
Field5: ''
}
];
}
handleUserInput(filterText) {
this.setState({filterText: filterText});
};
handleRowDel(phone) {
var index = this.state.phones.indexOf(phone);
this.state.phones.splice(index, 1);
this.setState(this.state.phones);
};
handleAddEvent(evt) {
var id = (+ new Date() + Math.floor(Math.random() * 999999)).toString(36);
var phone = {
id: id,
Phone_Number: '',
Type: '',
Receive_Calls: '',
Receive_Texts: '',
Preferred_Phone_Number: ''
}
this.state.phones.push(phone);
this.setState(this.state.phones);
}
handlephoneTable(evt) {
var item = {
id: evt.target.id,
name: evt.target.name,
value: evt.target.value
};
console.log('item.value in phone',item.value);
var phones = this.state.phones.slice();
var newphones = phones.map(function(phone) {
for (var key in phone) {
if (key == item.name && phone.id == item.id) {
phone[key] = item.value;
}
}
return phone;
});
this.setState({phones:newphones});
// console.log(this.state.phones);
};
render() {
return (
<div>
<PhoneTable onphoneTableUpdate={this.handlephoneTable.bind(this)} onRowAdd={this.handleAddEvent.bind(this)} onRowDel={this.handleRowDel.bind(this)} phones={this.state.phones} filterText={this.state.filterText}/>
</div>
);
}
}
class PhoneTable extends React.Component {
render() {
var onphoneTableUpdate = this.props.onphoneTableUpdate;
var rowDel = this.props.onRowDel;
var filterText = this.props.filterText;
var phone = this.props.phones.map(function(phone) {
if (phone.Type.indexOf(filterText) === -1) {
return;
}
return (<PhoneRow onphoneTableUpdate={onphoneTableUpdate} phone={phone} onDelEvent={rowDel.bind(this)} key={phone.id}/>)
});
return (
<div>
<th>Phone</th>
<button type="button" onClick={this.props.onRowAdd} className="btn btn-success pull-right">Add</button>
<table className="table table-bordered">
<thead>
<tr>
<th>Phone_Number</th>
<th>Type</th>
<th>Receive_Calls</th>
<th>Receive_Texts</th>
<th>Preferred_Phone_Number</th>
</tr>
</thead>
<tbody>
{phone}
</tbody>
</table>
</div>
);
}
}
class PhoneRow extends React.Component {
onDelEvent() {
this.props.onDelEvent(this.props.phone);
}
render() {
return (
<tr className="eachRow">
<EditableCell onphoneTableUpdate={this.props.onphoneTableUpdate} cellData={{
"type": "Field1",
value: this.props.phone.Field1,
id: this.props.phone.id
}}/>
<EditableCell onphoneTableUpdate={this.props.onphoneTableUpdate} cellData={{
type: "Field2",
value: this.props.phone.Field2,
id: this.props.phone.id
}}/>
<EditableCell onphoneTableUpdate={this.props.onphoneTableUpdate} cellData={{
type: "Field3",
value: this.props.phone.Field3,
id: this.props.phone.id
}}/>
<EditableCell onphoneTableUpdate={this.props.onphoneTableUpdate} cellData={{
type: "Field4",
value: this.props.phone.Field4,
id: this.props.phone.id
}}/>
<EditableCell onphoneTableUpdate={this.props.onphoneTableUpdate} cellData={{
type: "Field5",
value: this.props.phone.Field5,
id: this.props.phone.id
}}/>
<td className="del-cell">
<input type="button" onClick={this.onDelEvent.bind(this)} value="REMOVE" className="del-btn"/>
</td>
</tr>
);
}
}
class EditableCell extends React.Component {
render() {
return (
<td>
<input type='text' name={this.props.cellData.type} id={this.props.cellData.id} value={this.props.cellData.value} onChange={this.props.onphoneTableUpdate}/>
</td>
);
}
}
export default Phone;
答案 0 :(得分：1)
您可以将回调从父组件传递到子组件，以便子组件可以更新父组件中的状态。这是演示此示例代码：
class Parent extends React.Component {
constructor(props) {
super(props);
this.state = {
phone: ''
}
this.phoneChange = this.phoneChange.bind(this);
}
componentDidUpdate() {
console.log('Parent state:', this.state.phone);
}
phoneChange(phone) {
console.log('child value', phone)
this.setState({phone});
}
render() {
return (
<div>
Phone:
<Child
phoneChange = {
this.phoneChange
}
/>
</div>)
}
}
class Child extends React.Component {
constructor(props) {
super(props);
this.state = {
phone: ''
}
this.handleChange = this.handleChange.bind(this);
}
handleChange(e) {
const phone = e.target.value;
this.setState({
phone
})
this.props.phoneChange(phone);
}
render() {
return ( < input value = {
this.state.phone
}
onChange = {
this.handleChange
}
/>);
}
}
ReactDOM.render( < Parent / > ,
document.getElementById('root')
);<script src="https://unpkg.com/react@16/umd/react.development.js" crossorigin></script>
<script src="https://unpkg.com/react-dom@16/umd/react-dom.development.js" crossorigin></script>
<div id="root" />