undefined不是对象吗？

Question

我收到以下错误：

undefined 不是对象（评估 'item.id'）

我有这个。获取项目和删除项目：

    getItems = async () => {
    this.setState({ refreshing: true });
    this.unsubscribe = await this.ref.onSnapshot((querySnapshot) => {
          const todos = [];
          querySnapshot.forEach((doc) => {
            todos.push({
              id: doc.id,
              tips: doc.data().tips,
              date: doc.data().date,
              user: doc.data().user,
              like: doc.data().like,
            })
            this.ref.get().then(function(documentSnapshot) {
              // check and do something with the data here.
            });
          })
          this.setState({
            refreshing: false,
            getData: todos
          })
        })
  }
  deletePost({ item, index }){
    var deleteItemId = item.id;
     firestore.collection("tips").doc(deleteItemId).delete().then(function() {
          alert("deleted", deleteItemId)
      }).catch(function(error) {
          alert("Error removing document: ", error);
      });
  }

渲染的项目如：

renderItem = ({ item, index }) => {

    return (
        <Text onPress={() => this.deletePost(item.id)}>Delete</Text>
    )
 }

这是 item.id 就像NnX57tSpqvPvIUN7tRY4

Answer 1

看来你已经调用了undefined 的方法。确保item.id 不是undefined：

deleteItemId && firestore.collection("tips").doc(deleteItemId).delete()