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reactjs - Clear and reset form input fields

I have a form containing various input fields and two buttons; one for submitting and one for cancelling.

<form id="create-course-form">
  <input type="text" name="course_Name" ref="fieldName">
  <input type="text" name="course_org" ref="fieldOrg">
  <input type="text" name="course_Number" ref="fieldNum">

  <input type="submit" name="saveCourse" value="Create">
  <input type="button" name="cancelCourse" value="cancel" onClick={this.cancelCourse}>
</form>

What I want is to empty all inputs when the cancel button is clicked. So far I've managed to do this by using each input's ref prop.

cancelCourse(){
  this.refs.fieldName.value="";
  this.refs.fieldorg.value="";
  this.refs.fieldNum.value="";
}

However, I want to empty the input fields without having to empty each one seperately. I want something similar to this (jQuery): $('#create-course-form input[type=text]').val('');

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The answer here depends on whether or not your inputs are controlled or uncontrolled. If you are unsure or need more info on this, check out what the official docs say about controlled components and uncontrolled components. Thanks @Dan-Esparza for providing the links.

Also, please note that using string literals in ref is deprecated. Use the standard callback method instead.


Clearing a form with uncontrolled fields

You can clear the entire form rather than each form field individually.

cancelCourse = () => { 
  document.getElementById("create-course-form").reset();
}

render() {
  return (
    <form id="create-course-form">
      <input />
      <input />
      ...
      <input />
    </form>
  );
}

If your form didn't have an id attribute you could use a ref as well:

cancelCourse = () => { 
  this.myFormRef.reset();
}

render() {
  return (
    <form ref={(el) => this.myFormRef = el;}>
      <input />
      <input />
      ...
      <input />
    </form>
  );
}

Clearing a form with controlled fields

If you are using controlled form fields, you may have to explicitly reset each component inside your form, depending on how your values are stored in the state.

If they are declared individually, you need to reset each one explicitly:

cancelCourse = () => { 
  this.setState({
    inputVal_1: "",
    inputVal_2: "",
    ...
    inputVal_n: "",
  });
}

render() {
  return (
    <input value={this.state.inputVal_1} onChange={this.handleInput1Change}>
    <input value={this.state.inputVal_2} onChange={this.handleInput2Change}>
    ...
    <input value={this.state.inputVal_n} onChange={this.handleInputnChange}>
  );
}

Demo below:

class MyApp extends React.Component {
  constructor() {
    super();
    this.state = {
      inputVal_1: "",
      inputVal_2: "",
      inputVal_3: "",
      inputVal_4: "",
      inputVal_5: "",
      inputVal_6: "",
      inputVal_7: "",
      inputVal_8: "",
      inputVal_9: "",
      inputVal_10: ""
    };
  }
  
  handleInput1Change = (e) => {
    this.setState({inputVal_1: e.target.value});
  }
  
  handleInput2Change = (e) => {
    this.setState({inputVal_2: e.target.value});
  }
  
  handleInput3Change = (e) => {
    this.setState({inputVal_3: e.target.value});
  }
  
  handleInput4Change = (e) => {
    this.setState({inputVal_4: e.target.value});
  }
  
  handleInput5Change = (e) => {
    this.setState({inputVal_5: e.target.value});
  }
  
  handleInput6Change = (e) => {
    this.setState({inputVal_6: e.target.value});
  }
  
  handleInput7Change = (e) => {
    this.setState({inputVal_7: e.target.value});
  }
  
  handleInput8Change = (e) => {
    this.setState({inputVal_8: e.target.value});
  }
  
  handleInput9Change = (e) => {
    this.setState({inputVal_9: e.target.value});
  }
  
  handleInput10Change = (e) => {
    this.setState({inputVal_10: e.target.value});
  }
  
  cancelCourse = () => { 
    this.setState({
      inputVal_1: "",
      inputVal_2: "",
      inputVal_3: "",
      inputVal_4: "",
      inputVal_5: "",
      inputVal_6: "",
      inputVal_7: "",
      inputVal_8: "",
      inputVal_9: "",
      inputVal_10: ""
    });
  }
  
  render() {
    return (
      <form>
        <input value={this.state.inputVal_1} onChange={this.handleInput1Change} />
        <input value={this.state.inputVal_2} onChange={this.handleInput2Change} />
        <input value={this.state.inputVal_3} onChange={this.handleInput3Change} />
        <input value={this.state.inputVal_4} onChange={this.handleInput4Change} />
        <input value={this.state.inputVal_5} onChange={this.handleInput5Change} />
        <input value={this.state.inputVal_6} onChange={this.handleInput6Change} />
        <input value={this.state.inputVal_7} onChange={this.handleInput7Change} />
        <input value={this.state.inputVal_8} onChange={this.handleInput8Change} />
        <input value={this.state.inputVal_9} onChange={this.handleInput9Change} />
        <input value={this.state.inputVal_10} onChange={this.handleInput10Change} />
        <input type="submit" name="saveCourse" value="Create" />
        <input type="button" name="cancelCourse" value="cancel" onClick={this.cancelCourse} />
      </form>
    );
  }
}

ReactDOM.render(<MyApp />, document.getElementById("app"));
<script src="https://cdnjs.cloudflare.com/ajax/libs/react/15.1.0/react.min.js"></script>
<script src="https://cdnjs.cloudflare.com/ajax/libs/react/15.1.0/react-dom.min.js"></script>
<div id="app"></div>

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