从所选项目中删除和删除项目时，如何在反应选择中捕获添加和删除事件？

Question

handleChange(value) {
    let difference = this.state.selected.filter(x => !value.includes(x));
    console.log("Removed: ", difference);
    this.setState({
        selected: value
    });
}

Answer 1

To get notified about addition of values in react-select, i used onKeyDown prop. This method( handleKeyDown ) will be called when user enters any manual value and hits enter or tab to add values like below:

      <Select
        inputValue={inputValue}
        isClearable={false}
        isMulti
        onChange={this.handleChange}
        onInputChange={this.handleInputChange}
        onKeyDown={this.handleKeyDown}
        placeholder="Type something and press enter..."
        value={value}
      />

    handleKeyDown = event => {
    const { inputValue, value } = this.state;
    if (!inputValue) return;
    console.log("event.key:", event.key);
    switch (event.key) {
      case "Enter":
        const newValues = inputValue.split(",").map(x => createOption(x));
        this.setState({
          inputValue: "",
          value: [...value, ...newValues]
        });
        event.preventDefault();
        break;
      case "Tab":
        this.setState({
          inputValue: "",
          value: [...value, createOption(inputValue)]
        });
        event.preventDefault();
        break;
      default:
        console.log("Other events caught");
    }
  };

You can capture remove event using onChange prop. Below code shows that:

handleChange = (value, actionMeta) => {
    console.group("Inside handleChange");
    console.log(value);
    console.log(`action: ${actionMeta.action}`); // will capture remove event
    this.setState({ value });
  };

You can experiment in below sandbox. Above mentioned example is present in Sandbox: https://codesandbox.io/s/react-codesandboxer-example-7r2y6