Reactjs - Validation de saisie de formulaire

Question

Mon formulaire de page de contact est comme suit,

<form name="contactform" onSubmit={this.contactSubmit.bind(this)}>
  <div className="col-md-6">
    <fieldset>
      <input ref="name" type="text" size="30" placeholder="Name"/>
      <br/>
      <input refs="email" type="text" size="30" placeholder="Email"/>
      <br/>
      <input refs="phone" type="text" size="30" placeholder="Phone"/>
      <br/>
      <input refs="address" type="text" size="30" placeholder="Address"/>
      <br/>
    </fieldset>
  </div>
  <div className="col-md-6">
    <fieldset>
      <textarea refs="message" cols="40" rows="20"
                className="comments" placeholder="Message"/>
    </fieldset>
  </div>
  <div className="col-md-12">
    <fieldset>
      <button className="btn btn-lg pro" id="submit"
              value="Submit">Send Message</button>
    </fieldset>
  </div>
</form>

Besoin d'ajouter une validation pour tous les champs. Quelqu'un peut-il m'aider à ajouter une validation sous cette forme de réaction?

Answer 1

Vous devriez éviter d'utiliser des références, vous pouvez le faire avec la fonction onChange. 

À chaque modification, mettez à jour l'état du champ modifié.

Ensuite, vous pouvez facilement vérifier si ce champ est vide ou ce que vous voulez.

Vous pouvez faire quelque chose comme suit:

class Test extends React.Component {
    constructor(props){
       super(props);

       this.state = {
           fields: {},
           errors: {}
       }
    }

    handleValidation(){
        let fields = this.state.fields;
        let errors = {};
        let formIsValid = true;

        //Name
        if(!fields["name"]){
           formIsValid = false;
           errors["name"] = "Cannot be empty";
        }

        if(typeof fields["name"] !== "undefined"){
           if(!fields["name"].match(/^[a-zA-Z]+$/)){
              formIsValid = false;
              errors["name"] = "Only letters";
           }        
        }

        //Email
        if(!fields["email"]){
           formIsValid = false;
           errors["email"] = "Cannot be empty";
        }

        if(typeof fields["email"] !== "undefined"){
           let lastAtPos = fields["email"].lastIndexOf('@');
           let lastDotPos = fields["email"].lastIndexOf('.');

           if (!(lastAtPos < lastDotPos && lastAtPos > 0 && fields["email"].indexOf('@@') == -1 && lastDotPos > 2 && (fields["email"].length - lastDotPos) > 2)) {
              formIsValid = false;
              errors["email"] = "Email is not valid";
            }
       }  

       this.setState({errors: errors});
       return formIsValid;
   }

   contactSubmit(e){
        e.preventDefault();

        if(this.handleValidation()){
           alert("Form submitted");
        }else{
           alert("Form has errors.")
        }

    }

    handleChange(field, e){         
        let fields = this.state.fields;
        fields[field] = e.target.value;        
        this.setState({fields});
    }

    render(){
        return (
            <div>           
               <form name="contactform" className="contactform" onSubmit= {this.contactSubmit.bind(this)}>
                    <div className="col-md-6">
                      <fieldset>
                           <input ref="name" type="text" size="30" placeholder="Name" onChange={this.handleChange.bind(this, "name")} value={this.state.fields["name"]}/>
                           <span style={{color: "red"}}>{this.state.errors["name"]}</span>
                          <br/>
                         <input refs="email" type="text" size="30" placeholder="Email" onChange={this.handleChange.bind(this, "email")} value={this.state.fields["email"]}/>
                         <span style={{color: "red"}}>{this.state.errors["email"]}</span>
                         <br/>
                         <input refs="phone" type="text" size="30" placeholder="Phone" onChange={this.handleChange.bind(this, "phone")} value={this.state.fields["phone"]}/>
                         <br/>
                         <input refs="address" type="text" size="30" placeholder="Address" onChange={this.handleChange.bind(this, "address")} value={this.state.fields["address"]}/>
                         <br/>
                     </fieldset>
                  </div>

              </form>
            </div>
      )
    }
}

React.render(<Test />, document.getElementById('container'));

Dans cet exemple, je n'ai validé que le courrier électronique et le nom, mais vous avez une idée de la procédure à suivre. Pour le reste, vous pouvez le faire vous-même.

Il y a peut-être un meilleur moyen, mais vous aurez l'idée.

Voici le violon.

J'espère que cela t'aides.

Answer 2

J'ai pris votre code et l'ai adapté à la bibliothèque react-form-with-contrainte : https://codepen.io/tkrotoff/pen/LLraZp

const {
  FormWithConstraints,
  FieldFeedbacks,
  FieldFeedback
} = ReactFormWithConstraints;

class Form extends React.Component {
  handleChange = e => {
    this.form.validateFields(e.target);
  }

  contactSubmit = e => {
    e.preventDefault();

    this.form.validateFields();

    if (!this.form.isValid()) {
      console.log('form is invalid: do not submit');
    } else {
      console.log('form is valid: submit');
    }
  }

  render() {
    return (
      <FormWithConstraints
        ref={form => this.form = form}
        onSubmit={this.contactSubmit}
        noValidate>

        <div className="col-md-6">
          <input name="name" size="30" placeholder="Name"
                 required onChange={this.handleChange}
                 className="form-control" />
          <FieldFeedbacks for="name">
            <FieldFeedback when="*" />
          </FieldFeedbacks>

          <input type="email" name="email" size="30" placeholder="Email"
                 required onChange={this.handleChange}
                 className="form-control" />
          <FieldFeedbacks for="email">
            <FieldFeedback when="*" />
          </FieldFeedbacks>

          <input name="phone" size="30" placeholder="Phone"
                 required onChange={this.handleChange}
                 className="form-control" />
          <FieldFeedbacks for="phone">
            <FieldFeedback when="*" />
          </FieldFeedbacks>

          <input name="address" size="30" placeholder="Address"
                 required onChange={this.handleChange}
                 className="form-control" />
          <FieldFeedbacks for="address">
            <FieldFeedback when="*" />
          </FieldFeedbacks>
        </div>

        <div className="col-md-6">
          <textarea name="comments" cols="40" rows="20" placeholder="Message"
                    required minLength={5} maxLength={50}
                    onChange={this.handleChange}
                    className="form-control" />
          <FieldFeedbacks for="comments">
            <FieldFeedback when="*" />
          </FieldFeedbacks>
        </div>

        <div className="col-md-12">
          <button className="btn btn-lg btn-primary">Send Message</button>
        </div>
      </FormWithConstraints>
    );
  }
}

Capture d'écran:

 

C'est un hack rapide. Pour une démonstration appropriée, consultez https://github.com/tkrotoff/react-form-with-constraints#examples

Answer 3

import React from 'react';
import {sendFormData} from '../services/';

class Signup extends React.Component{
  constructor(props){
    super(props);
     this.state = {
       isDisabled:true
     }                                                                                                 
     this.submitForm = this.submitForm.bind(this);
  }
  validateEmail(email){
   const pattern = /[a-zA-Z0-9]+[\.]?([a-zA-Z0-9]+)?[\@][a-z]{3,9}[\.][a-z]{2,5}/g;
   const result = pattern.test(email);
   if(result===true){
     this.setState({
       emailError:false,
       email:email
     })
   } else{
     this.setState({
       emailError:true
     })
   }
 }
 handleChange(e){
  const target = e.target;
  const value = target.type === 'checkbox' ? target.checked : target.value;
  const name = target.name;
  this.setState({
    [name]: value
  });
  if(e.target.name==='firstname'){
    if(e.target.value==='' || e.target.value===null ){
      this.setState({
        firstnameError:true
      })
    } else {
      this.setState({
        firstnameError:false,     
        firstName:e.target.value
      })
    }
  }
  if(e.target.name==='lastname'){
    if(e.target.value==='' || e.target.value===null){
      this.setState({
        lastnameError:true
      })
    } else {
      this.setState({
        lastnameError:false,
        lastName:e.target.value
      })
    }
  }
  if(e.target.name==='email'){
   this.validateEmail(e.target.value);
  }
  if(e.target.name==='password'){
    if(e.target.value==='' || e.target.value===null){
      this.setState({
        passwordError:true
      })
    } else {
      this.setState({
        passwordError:false,
        password:e.target.value
      })
    }
 }
 if(this.state.firstnameError===false && this.state.lastnameError===false && 
  this.state.emailError===false && this.state.passwordError===false){
    this.setState({
      isDisabled:false
    })
 }
}
submitForm(e){
  e.preventDefault();
  const data = {
   firstName: this.state.firstName,
   lastName: this.state.lastName,
   email: this.state.email,
   password: this.state.password
  }
  sendFormData(data).then(res=>{
    if(res.status===200){
      alert(res.data);
      this.props.history.Push('/');
    }else{

    } 
  });
 }
render(){
return(
  <div className="container">
    <div className="card card-login mx-auto mt-5">
      <div className="card-header">Register here</div>
        <div className="card-body">
            <form id="signup-form">
              <div className="form-group">
                <div className="form-label-group">
                  <input type="text" id="firstname" name="firstname" className="form-control" placeholder="Enter firstname" onChange={(e)=>{this.handleChange(e)}} />
                  <label htmlFor="firstname">firstname</label>
                  {this.state.firstnameError ? <span style={{color: "red"}}>Please Enter some value</span> : ''} 
                </div>
              </div>
              <div className="form-group">
                <div className="form-label-group">
                  <input type="text" id="lastname" name="lastname" className="form-control" placeholder="Enter lastname" onChange={(e)=>{this.handleChange(e)}} />
                  <label htmlFor="lastname">lastname</label>
                  {this.state.lastnameError ? <span style={{color: "red"}}>Please Enter some value</span> : ''}
                </div>
              </div>
              <div className="form-group">
                <div className="form-label-group">
                  <input type="email" id="email" name="email" className="form-control" placeholder="Enter your email" onChange={(e)=>{this.handleChange(e)}} />
                  <label htmlFor="email">email</label>
                  {this.state.emailError ? <span style={{color: "red"}}>Please Enter valid email address</span> : ''}
                </div>
              </div>                
              <div className="form-group">
                <div className="form-label-group">
                  <input type="password" id="password" name="password" className="form-control" placeholder="Password" onChange={(e)=>{this.handleChange(e)}} />
                  <label htmlFor="password">Password</label>
                  {this.state.passwordError ? <span style={{color: "red"}}>Please enter some   value</span> : ''}
                </div>
              </div>                
              <button className="btn btn-primary btn-block" disabled={this.state.isDisabled} onClick={this.submitForm}>Signup</button>
            </form>
        </div>
      </div>
    </div>
  );
 }
}
export default Signup;

Answer 4

Peut-être tard pour répondre - si vous ne voulez pas beaucoup modifier votre code actuel et que vous pouvez toujours avoir un code de validation similaire dans tout votre projet, vous pouvez aussi essayer celui-ci - https://github.com/vishalvisd/react-validator .