Arrow functions with async and await in react native

问题

I am trying to save data in AsyncStorage in react-native. I want to save it asynchronous so using async and await keyword.

  async onPositiveClickListener = () => {
    // user has completed product tour_end
    try {
      await AsyncStorage.setItem("@ProductTour:key", "true");
      const { navigate } = this.props.navigation;
      navigate("DashboardScreen");
    } catch (error) {
      console.log(error);
    }
  };

I am getting an error while saving program

SyntaxError: Unexpected token, expected ( (40:32)
  38 |   };
  39 | 
> 40 |   async onPositiveClickListener = () => {
     |                                 ^
  41 |     // save user has completed product tour_end
  42 |     try {
  43 |       await AsyncStorage.setItem("@ProductTour:key", "true");
Hide Stack Trace
SyntaxError: Unexpected token, expected ( (40:32)
  38 |   };
  39 | 
> 40 |   async onPositiveClickListener = () => {
     |                                 ^
  41 |     // save user has completed product tour_end
  42 |     try {

回答1:

Async named arrow function should be declared like

const onPositiveClickListener = async () => {
    // user has completed product tour_end
    try {
      await AsyncStorage.setItem("@ProductTour:key", "true");
      const { navigate } = this.props.navigation;
      navigate("DashboardScreen");
    } catch (error) {
      console.log(error);
    }
  };

来源：https://stackoverflow.com/questions/43718103/arrow-functions-with-async-and-await-in-react-native