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Pass data between two react components in MERN stack

I am trying to build an E commerce web app where I handle the payments. First I need to take shipping information. I have successfully inserted data into mongo but I could not pass the data into another js right away from a single click.
Here is my create address page.
import React, { Component } from 'react'
import '../App.css'
import axios from 'axios'
export default class CreateAddress extends Component {
constructor(props) {
super(props);
this.state = {
address: "",
city: "",
phoneNo:"",
postalCode: "",
country: ""
}
}
handleInputChange = (e)=>{
const {name,value} = e.target;
this.setState({
...this.state,
[name]:value
})
}
onSubmit = (e)=>{
e.preventDefault();
const {address,city,phoneNo,postalCode,country} = this.state;
const data = {
address: address,
city: city,
phoneNo: phoneNo,
postalCode: postalCode,
country: country
}
console.log(data)
axios.post("http://localhost:5000/address/save",data).then((res)=>{
if(res.data.success){
this.setState(
{address: "",
city: "",
phoneNo:"",
postalCode: "",
country: ""}
)
alert("Shipping info added successfully");
}
})
}
render() {
return (
<div className="row wrapper">
<div className="col-10 col-lg-5">
<form className="shadow-lg" >
<h1 className="mb-4">Shipping Info</h1>
<div className="form-group">
<label htmlFor="address_field">Address</label>
<input
type="text"
id="address_field"
className="form-control"
name='address'
value={this.state.address}
onChange={this.handleInputChange}
required
/>
</div>
<div className="form-group">
<label htmlFor="city_field">City</label>
<input
type="text"
id="city_field"
className="form-control"
name='city'
value={this.state.city}
onChange={this.handleInputChange}
required
/>
</div>
<div className="form-group">
<label htmlFor="phone_field">Phone No</label>
<input
type="phone"
id="phone_field"
className="form-control"
name='phoneNo'
value={this.state.phoneNo}
onChange={this.handleInputChange}
required
/>
</div>
<div className="form-group">
<label htmlFor="postal_code_field">Postal Code</label>
<input
type="number"
id="postal_code_field"
className="form-control"
name='postalCode'
value={this.state.postalCode}
onChange={this.handleInputChange}
required
/>
</div>
<div className="form-group">
<label htmlFor="country_field">Country</label>
<input
type = "text"
id="country_field"
className="form-control"
name='country'
value={this.state.country}
onChange={this.handleInputChange}
required
/>
</div>
<button
id="shipping_btn"
type="submit"
className="btn btn-block py-3"
onClick={this.onSubmit}
>
SAVE
</button>
<button id="shipping_btn" type="submit" className = "btn btn-block py-3"><a href = "/confirm" style={{textDecoration:'none',color:'white'}}>PROCEED</a></button>
</form>
</div>
</div>
)
}
}
Once I clicked the PROCEED button the data should direct into /confirm page

You can use react-router to move between different routes in React. Also, in your code when you are sending a post request on onSubmit method, you are clearing the state information, which I think needs to be handled in the confirm page since you need the data in that page also.
Here's a codesandbox demonstrating how you can send the information to another page, using react-router. I've used the functional components, but the concepts works for the class based components also.
note: also you should use onSubmit handler of the form to submit values rather than using the onClick method of the button. Otherwise you force users to click the button to submit the form.

You can use history API to pass data as a URL and grab it into confirm page.
history.push(`/confirmPage?city=${city}&postalCode=${postalCode}`)
in confirmPage.js you will get that data as props
export default class ConfirmPage extends Component{
render(){
const {city, postalCode } = this.props.location.query;
return (
<div>{postalCode}</div>
)
}

how to set props values of controls in react js

I am new to react. I have almost 15 input controls on UI. Some are dropdowns, some are textboxes, couple of calender controls and radio buttons. I want to retrive all values before submitting a page. Do I need to define 15 props in state object of component for 15 inputs? is there any way to have it in one object.
Also how to set the values of each control. For example for textbox I know, its like
<input type="text" name="username" className="form-control" id="exampleInput" value={this.props.name} onChange={this.handleChange} placeholder="Enter name"></input>
How to handle same for dropdown,calender and radio buttton. Thanks in advance.

Normally, these wouldn't be props, they'd be state (which is different). You can use objects in state. If you're doing a class-based component (class YourComponent extends React.Component), state is always an object you create in the constructor and update with setState. If you're doing this in a function component, typically you use separate state variables for each thing (const [name, setName] = useState("");), but you can use an object if you prefer. There's more about state in the documentation.
That said, if you only want the values when you take an action, you could make the inputs "uncontrolled."
Here's a three-input example using a class component:
class Example extends React.Component {
constructor(props) {
super(props);
this.state = {
firstName: "",
lastName: "",
about: ""
};
this.handleChange = this.handleChange.bind(this);
}
handleChange({target: {name, value}}) {
this.setState({[name]: value});
}
render() {
const {firstName, lastName, about} = this.state;
const {handleChange} = this;
return <div>
<div>
<label>
First name:
<br/>
<input type="text" value={firstName} name="firstName" onChange={handleChange} />
</label>
</div>
<div>
<label>
Last name:
<br/>
<input type="text" value={lastName} name="lastName" onChange={handleChange} />
</label>
</div>
<div>
<label>
About you:
<br />
<textarea value={about} name="about" onChange={handleChange} />
</label>
</div>
<div>{firstName} {lastName} {(firstName || lastName) && about ? "-" : ""} {about}</div>
</div>;
}
}
ReactDOM.render(<Example/>, document.getElementById("root"));
<div id="root"></div>
<script src="https://cdnjs.cloudflare.com/ajax/libs/react/16.12.0/umd/react.production.min.js"></script>
<script src="https://cdnjs.cloudflare.com/ajax/libs/react-dom/16.12.0/umd/react-dom.production.min.js"></script>
Here's one using a functional component with discrete state items (usually best):
const { useState } = React;
const Example = () => {
const [firstName, setFirstName] = useState("");
const [lastName, setLastName] = useState("");
const [about, setAbout] = useState("");
// There's are lots of ways to do this part, this is just one of them
const handleChange = ({target: {name, value}}) => {
switch (name) {
case "firstName":
setFirstName(value);
break;
case "lastName":
setLastName(value);
break;
case "about":
setAbout(value);
break;
}
};
return <div>
<div>
<label>
First name:
<br/>
<input type="text" value={firstName} name="firstName" onChange={handleChange} />
</label>
</div>
<div>
<label>
Last name:
<br/>
<input type="text" value={lastName} name="lastName" onChange={handleChange} />
</label>
</div>
<div>
<label>
About you:
<br />
<textarea value={about} name="about" onChange={handleChange} />
</label>
</div>
<div>{firstName} {lastName} {(firstName || lastName) && about ? "-" : ""} {about}</div>
</div>;
}
ReactDOM.render(<Example/>, document.getElementById("root"));
<div id="root"></div>
<script src="https://cdnjs.cloudflare.com/ajax/libs/react/16.12.0/umd/react.production.min.js"></script>
<script src="https://cdnjs.cloudflare.com/ajax/libs/react-dom/16.12.0/umd/react-dom.production.min.js"></script>
Here's one using a functional component with an object in state:
const { useState } = React;
const Example = () => {
const [data, setData] = useState({firstName: "", lastName: "", about: ""});
const handleChange = ({target: {name, value}}) => {
setData(current => ({...current, [name]: value}));
};
const {firstName, lastName, about} = data;
return <div>
<div>
<label>
First name:
<br/>
<input type="text" value={firstName} name="firstName" onChange={handleChange} />
</label>
</div>
<div>
<label>
Last name:
<br/>
<input type="text" value={lastName} name="lastName" onChange={handleChange} />
</label>
</div>
<div>
<label>
About you:
<br />
<textarea value={about} name="about" onChange={handleChange} />
</label>
</div>
<div>{firstName} {lastName} {(firstName || lastName) && about ? "-" : ""} {about}</div>
</div>;
}
ReactDOM.render(<Example/>, document.getElementById("root"));
<div id="root"></div>
<script src="https://cdnjs.cloudflare.com/ajax/libs/react/16.12.0/umd/react.production.min.js"></script>
<script src="https://cdnjs.cloudflare.com/ajax/libs/react-dom/16.12.0/umd/react-dom.production.min.js"></script>

Here is the sample code, I used in my application.
class CreditCardForm extends React.Component {
constructor() {
super()
this.state = {
name: '',
address: '',
ccNumber: ''
}
}
handleChange(e) {
// If you are using babel, you can use ES 6 dictionary syntax
// let change = { [e.target.name] = e.target.value }
let change = {}
change[e.target.name] = e.target.value
this.setState(change)
}
render() {
return (
<form>
<h2>Enter your credit card details</h2>
<label>
Full Name
<input type="name" onChange={(e)=>this.handleChange(e)} value={this.state.name} />
</label>
<label>
Home address
<input type="address" onChange={(e)=>this.handleChange(e)} value={this.state.address} />
</label>
<label>
Credit card number
<input type="ccNumber" onChange={(e)=>this.handleChange(e)} maxlength="16" value={this.state.ccNumber} />
</label>
<button type="submit">Pay now</button>
</form>
)
}
}

You can set name for input and update state base on event.target.name and event.target.value
constructor() {
super();
this.state = {
text: "",
select: "",
radio: ""
};
}
handeInput = e => {
this.setState({
[e.target.name]: e.target.value
});
};
render() {
console.log(this.state);
return (
<div className="App">
<input
onChange={this.handeInput}
type="input"
name="text"
value={this.state.text}
/>
<select
name="select"
onChange={this.handeInput}
value={this.state.select}
>
<option value="option1">option1</option>
<option value="option2">option2</option>
</select>
<input
type="radio"
name="radio"
value="Option1"
checked={this.state.radio === "Option1"}
onChange={this.handeInput}
/>
Option1
<input
type="radio"
name="radio"
value="Option2"
checked={this.state.radio === "Option2"}
onChange={this.handeInput}
/>
Option2
</div>
);
}
You can check here CodeSandBox Hope it helps

Storing each input's data in its respective state

I have three inputs, and I want each input's data to be stored in a state. For example, the name input should be stored in the name state, because I'll need it later to push the three states' values in a firebase database.
I used the onChange function to store the data, but I didn't know how to make each input's function relative to the state I want to put it in.
import React from "react";
import ReactDOM from "react-dom";
export default class Inputs extends React.Component {
constructor(props) {
super(props);
this.state = {
name: "",
email: "",
age: ""
};
}
handleChange = e => {
this.setState({ name: e.target.value });
};
render() {
return (
<div>
<form>
<label>
name:
<input type="text" name="name" onChange={this.handleChange} />
</label>
<label>
email:
<input type="text" name="email" onChange={this.handleChange} />
</label>
<label>
age:
<input type="text" name="age" onChange={this.handleChange} />
</label>
<input type="submit" value="Submit" />
</form>
<textarea value={this.state.value} onChange={this.handleChange} />
<button onClick={() => this.props.onClick(this.state.value)}>
Add task
</button>
</div>
);
}
}

getChanges = (e) => {
console.log(e);
this.setState({[e.target.name]: e.target.value}, function () {
console.log(this.state)
})
};
call this function,
<Input onChange={(e) => this.getChanges(e)} name={'name'}
value={this.state.name} placeholder={'Name'}/>

You can pass key and value
<input type="text" name="name" onChange={(event)=>this.handleChange(event,'name')} />
and in your function you can do something like this
handleChange = (e,key) => {
this.setState({ [key] : e.target.value });
};

React how to bind to component when calling onSubmit

In my component, I'm trying to call in an handleChange and handleSubmit functions of a component
If I render like the forms example,
<form onSubmit={this.handleSubmit}>
<input type="text" value={this.state.value} onChange={this.handleChange} placeholder="Enter new title"/>
<input type="submit" value="Submit" />
</form>
in onChange(), this won't be bound to the component, and I can't call this.setState, so I bind it with onChange={() => this.handleChange}.
for onSubmit(), I have the same binding problem, but when I bind it, the handler is not called, and the page is reloaded. What is the right way to bind to the component when submitting?
TIA
Full example:
class CbList extends React.Component {
constructor() {
super();
this.state = {
newTitle: '',
list: []
};
}
handleChange(event) {
this.setState(Object.assign({},
this.state,
{ newTitle: event.target.value }));
}
handleSubmit(event) {
this.addBlock(this.state.newTitle);
event.preventDefault();
return false;
}
render() {
return (
<div className="cb-list">
<div>
<form onSubmit={() => this.handleSubmit}>
<input type="text" value={this.state.value} onChange={() => this.handleChange}
placeholder="Enter new title"/>
<input type="submit" value="Submit" />
</form>
</div>
</div>
);
}
addBlock(title) {
let updatedList = this.state.list.concat({ title: title });
this.setState({ list: updatedList })
}
};
$(function() {
ReactDOM.render(<CbList/>, $('#home').get(0));
});

You forgot to invoke the functions:
onSubmit={()=>this.handleSubmit}
should be
onSubmit={()=>this.handleSubmit()}
Or, just pass a reference to the function:
onSubmit={this.handleSubmit}
but you'll need to bind your functions in the constructor (as show in the forms example link):
this.handleSubmit = this.handleSubmit.bind(this);

You need to bind you event handlers on constructor so you can use them among other events.
constructor(props) {
super(props)
this.handleSubmit = this.handleSubmit.bind(this)
this.handleChange = this.handleChange.bind(this)
}
Also, you don't need arrow function when using then as props.
<form onSubmit={this.handleSubmit}>
<input
type="text"
value={this.state.value}
onChange={this.handleChange}
placeholder="Enter new title"
/>
<input type="submit" value="Submit" />
</form>

Need to get the multiple form elements in uncontrolled components in reactjs

i am trying to get the multiple form fields input values and sending that to server. But i am only able to get the last field's value on submit.
I am using uncontrolled component because i am trying to editing the form and then updating it.Please help me out to get all the form details entered in the form.
import React from 'react';
import axios from 'axios';
class Update extends React.Component {
constructor(props) {
super(props);
this.state = {
info:''
};
this.handleSubmit = this.handleSubmit.bind(this);
}
handleSubmit(event) {
event.preventDefault();
console.log(event);
alert(event);
}
componentDidMount(){
let self = this;
axios.get('http://localhost:8080/studentById')
.then(function(data) {
//console.log(data);
self.setState({info:data.data});
});
}
render() {
return (
<div>
<form onSubmit={this.handleSubmit} >
<label className="w3-label w3-text-blue w3-large w3-margin-0 ">
First Name:
<input autoFocus type="text" className="w3-input w3-border" defaultValue={this.state.info.Firstname} ref={(input) => this.input = input} required />
</label>
<label className="w3-label w3-text-blue w3-large">
Last Name:
<input type="text" className="w3-input w3-border" defaultValue={this.state.info.Lastname} ref={(input) => this.input = input} required />
</label>
<input className="w3-btn-block w3-blue w3-margin-bottom w3-large" type="submit" value="Submit" />
</div>
)};
}

In your code, you assign all refs to the same variable. (your code simplified for showing what I mean)
First Name:
<input ref={(input) => this.input = input} />
Last Name:
<input ref={(input) => this.input = input} />
Instead use different variable for different input fields:
First Name:
<input ref={(input) => this.firstNameInput = input} />
Last Name:
<input ref={(input) => this.lastNameInput = input} />

You should use different property names for each input inside refs callbacks (currently you override this.input so it points to the last input):
<input autoFocus type="text" className="w3-input w3-border" defaultValue={this.state.info.Firstname} ref={(input) => this.input1 = input} required />
<input autoFocus type="text" className="w3-input w3-border" defaultValue={this.state.info.Firstname} ref={(input) => this.input2 = input} required />
Then inside your component methods you can access value of an input this way:
let inputValue = this.input1.value;