Small library to simplify the use of forms in React

With a simple higher-order component (HOC), you can get:

1. The values of the inputs.
2. The status of the form.
3. Control of validations.

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Examples.

• Simple Form
• Advanced Form
• Field Generator Form
• Custom Fields Use of the getInput interface ({ name, value, onChange}). IMPORTANT: onChange parameter is an object with target and the value: onChange({ target: { value } });

Getting Started

Installation

You can install with NPM: @jkr26/react-forms-builder-logic

npm i --save @jkr26/react-forms-builder-logic 

Step 1: Create your component and do the HOC

import { formWrapper, Form } from "@jkr26/react-forms-builder-logic";

class ExampleFormComponent extends React.Component {
  ...
}

export const ExampleForm = formWrapper(ExampleFormComponent);

Step 2: Add the fields and initialize the form.

  ...
  constructor(props) {
    super(props);
    this.setFields();
  }

  setFields() {
    this.props.form.initForm({
      name: {
        defaultValue: "asdasd",
        validators: [minStringValidator, maxStringValidator, isRequired]
      },
      age: {
        defaultValue: "2017-06-01",
        validators: [isRequired]
      },
      email: {
        defaultValue: "[email protected]",
        validators: [emailValidator, isRequired]
      },
      repeatEmail: {
        validators: [equalValidatorEmail, isRequired]
      },
      policyPrivacy: {
        defaultValue: true,
        validators: [isRequired]
      }
    },
    true
    );
  }
  ...

initForm second param optional: true for validation fields in real time || [default] false only in submit state

Step 3: Do not forget, add to each of the fields of your html form your handler (props.form.getInput, props.form.getSelect, ...)

  ...
  render() {
    const { form } = this.props;
    return (
      <div>
        <Form form={form}>
          Name:
          <input type="text" {...form.getInput("name")} />
        
          Age:
          <input type="date" {...form.getInput("age")} />
          
          Email:
          <input type="text" {...form.getInput("email")} />
          
          Repeat email:
          <input type="text" {...form.getInput("repeatEmail")} />
          
          Condiciones de privacidad:
          <input type="checkbox" {...form.getCheckbox("policyPrivacy")} />
          
          <button>Submit</button>
        </Form>
      </div>
    );
  }
  ...

Step 4: Wrapper form html

    ...
    <Form form={form}>
    ...

Step 5: Finally, you will receive the result of the form by props, "componentDidUpdate"

    ...
    componentDidUpdate() {
        if (this.props.form.isValidAfterSubmit) {
        console.log("Send data:", this.props.form.values);
        }
    }
    ...

Optional: you can get the errors of each of the fields

    ...
    render() {
        ...
        <Form form={form}>
          Name:
          <input type="text" {...form.getInput("name")} />
          {form.getErrors("name").map(e => (
            <span key={e} style={{ color: "red" }}>
              {e}
            </span>
          ))}

          Age:
          <input type="date" {...form.getInput("age")} />
          {form.getErrors("age").map(e => (
            <span key={e} style={{ color: "red" }}>
              {e}
            </span>
          ))}
    ...

• You can also get all the errors, with props props.form.errors.

Optional: control submit

    ...
    handleSubmit = e => {
      e.preventDefault();
      (...)
      this.props.form.submit();
    };

    render() {
        ...
        <Form form={form}>
          Name:
          <input type="text" {...form.getInput("name")} />
          {form.getErrors("name").map(e => (
            <span key={e} style={{ color: "red" }}>
              {e}
            </span>
          ))}

          <button onClick={this.handleSubmit}>
            Submit
          </button>
    ...

Doc

Functions

function	params	description
initForm()	{ exampleFieldName: { defaultValue: "foo", validators: [Validator1, Validator2, ValidatorN ] } }, boolean	Add the init form fields, along with their default value and validations. The second parameter indicates validations in real time, by default false. Method used in the contructor()
setFields()	{ exampleFieldName: { defaultValue: "foo", validators: [Validator1, Validator2, ValidatorN ] } }	Add the form fields, along with their default value and validations.
setValues()	{ nameField1: "foo", nameField2: "var", nameFieldN: "test" }	Set values. The form must have the loading to false.
clear()	no params	Set default values ​​for errors, values ​​and isValidAfterSubmit.
getErrors()	nameField	Get the errors of a field. Returns an error array or an empty one.
getInput()	nameField	Get input attributes. Only text, number and date.
getSelect()	nameField	Get input attributes. Only for select.
getCheckbox()	nameField	Get input attributes. Only for simple checkbox: true/false.
getRadio()	"nameField" , "value"	Get input attributes. Only for radio type.
getCheckboxMulti()	"nameField" , "value"	Get input attributes. Only for check with multiple options.

Render props

prop	types	default value	description
errors	{ elementKey: String[], ... }	{}	Errors by fields.
values	{ element: String, ... }	{}	Values by fields.
isValidAfterSubmit	boolean	false	All fields comply with their validations. After submit().
isValid	boolean	false	All fields comply with their validations in real time. Example: <button style={{ backgroundColor: form.isValid ? "green" : "red" }}>Submit</button>
init	boolean	true	false, when the form is ready. After initForm().

Component Form

Although the philosophy is not to create components, for the best control of the form we had to create a Form component to guarantee the load cycles and the alerts of uncontrolled components when they change to controlled:

    ...
    <Form form={this.props.form}>
    ...

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Validations

Example

The validation "isRequired" is included in the library.

Other examples of validation:

import { Validator } from "@jkr26/react-forms-builder-logic";
export const startWithJJ = new Validator(value => {
  const error = "The element must start with jj.";
  if (value && /^jj/.test(value)) {
    return false;
  }
  return error;
});

export const maxStringValidator = new Validator(value => {
  const error = "The item must have less than 10 characters.";
  if (value && value.length < 10) {
    return false;
  }
  return error;
});

export const emailValidator = new Validator(value => {
  const error = "Invalid email";
  const emailPattern = /^(([^<>()\[\]\\.,;:\s@"]+(\.[^<>()\[\]\\.,;:\s@"]+)*)|(".+"))@((\[[0-9]{1,3}\.[0-9]{1,3}\.[0-9]{1,3}\.[0-9]{1,3}\])|(([a-zA-Z\-0-9]+\.)+[a-zA-Z]{2,}))$/;
  if (value && emailPattern.test(String(value).toLowerCase())) {
    return false;
  }
  return error;
});

export const equalValidatorEmail = new Validator((value, formFields) => {
  const error = "THE EMAIL DOES NOT MATCH.";
  if (value && value === formFields.email.value) {
    return false;
  }
  return error;
});

The validators work in a very simple way, as the first parameter they receive the value of the element and as a second parameter they receive all the values ​​of the form, as an object: formFields = { name: "John", age: "33", email: "[email protected]", repeatEmail: "john" }

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MIT License.

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