How to set a default value in react-select

问题

i have an issue using react-select. I use redux form and i've made my react-select component compatible with redux form. Here is the code:

const MySelect = props => (
    <Select
        {...props}
        value={props.input.value}
        onChange={value => props.input.onChange(value)}
        onBlur={() => props.input.onBlur(props.input.value)}
        options={props.options}
        placeholder={props.placeholder}
        selectedValue={props.selectedValue}
      />
    );

and here how i render it:

<div className="select-box__container">
                  <Field
                    id="side"
                    name="side"
                    component={SelectInput}
                    options={sideOptions}
                    clearable={false}
                    placeholder="Select Side"
                    selectedValue={label: 'Any', value: 'Any'}
                  />
                </div>

But the problem is that that my dropdown has not a default value as i wish. What i'm doing wrong? Any ideas?

回答1:

I guess you need something like this:

const MySelect = props => (
<Select
    {...props}
    value={props.options.filter(option => option.label === 'Some label')}
    onChange={value => props.input.onChange(value)}
    onBlur={() => props.input.onBlur(props.input.value)}
    options={props.options}
    placeholder={props.placeholder}
  />
);

回答2:

I used the defaultValue parameter, below is the code how I achieved a default value as well as update the default value when an option is selected from the drop-down.

<Select
  name="form-dept-select"
  options={depts}
  defaultValue={{ label: "Select Dept", value: 0 }}
  onChange={e => {
              this.setState({
              department: e.label,
              deptId: e.value
              });
           }}
/>

回答3:

If you've come here for react-select v2, and still having trouble - version 2 now only accepts an object as value, defaultValue, etc.

That is, try using value={{value: 'one', label: 'One'}}, instead of just value={'one'}.

回答4:

I was having a similar error. Make sure your options have a value attribute.

<option key={index} value={item}> {item} </option>

Then match the selects element value initially to the options value.

<select 
    value={this.value} />

回答5:

I just went through this myself and chose to set the default value at the reducer INIT function.

If you bind your select with redux then best not 'de-bind' it with a select default value that doesn't represent the actual value, instead set the value when you initialize the object.

回答6:

Extending on @isaac-pak's answer, if you want to pass the default value to your component in a prop, you can save it in state in the componentDidMount() lifecycle method to ensure the default is selected the first time.

Note, I've updated the following code to make it more complete and to use an empty string as the initial value per the comment.

export default class MySelect extends Component {

    constructor(props) {
        super(props);
        this.state = {
            selectedValue: '',
        };
        this.handleChange = this.handleChange.bind(this);

        this.options = [
            {value: 'foo', label: 'Foo'},
            {value: 'bar', label: 'Bar'},
            {value: 'baz', label: 'Baz'}
        ];

    }

    componentDidMount() {
        this.setState({
            selectedValue: this.props.defaultValue,
        })
    }

    handleChange(selectedOption) {
        this.setState({selectedValue: selectedOption.value});
    }

    render() {
        return (
            <Select
                value={this.options.filter(({value}) => value === this.state.selectedValue)}
                onChange={this.handleChange}
                options={this.options}
            />
        )
    }
}

MySelect.propTypes = {
    defaultValue: PropTypes.string.isRequired
};

回答7:

If your options are like this

var options = [
  { value: 'one', label: 'One' },
  { value: 'two', label: 'Two' }
];

Your {props.input.value} should match one of the 'value' in your {props.options}

Meaning, props.input.value should be either 'one' or 'two'

回答8:

If you are not using redux-form and you are using local state for changes then your react-select component might look like this:

class MySelect extends Component {

constructor() {
    super()
}

state = {
     selectedValue: 'default' // your default value goes here
}

render() {
  <Select
       ...
       value={this.state.selectedValue}
       ...
  />
)}

回答9:

To auto-select the value of in select.

<div className="form-group">
    <label htmlFor="contactmethod">Contact Method</label>
    <select id="contactmethod" className="form-control"  value={this.state.contactmethod || ''} onChange={this.handleChange} name="contactmethod">
    <option value='Email'>URL</option>
    <option value='Phone'>Phone</option>
    <option value="SMS">SMS</option>
    </select>
</div>

Use the value attribute in the select tag

value={this.state.contactmethod || ''}

the solution is working for me.

来源：https://stackoverflow.com/questions/43495696/how-to-set-a-default-value-in-react-select

标签

reactjs

default-value

react-select