尝试读取超出范围（63）的数组索引（63）。请先检查长度。 MobX将不会跟踪超出范围的索引

Question

我正在使用可跟踪的变量，我将搜索该值但是设置数据时出错我已搜索出出现此错误但找不到的原因。

class TurListesiStore {
  @observable list = [];
  @action async getTurList() {
    this.loading = true;


    try {
      const { data } = await axios..

      runInAction(() => {

        let listx = data.KusTurleriListesi;
        let list = [];
        for (let i = 0; i < listx.length; i++) {
          let y = { data: listx[i].TurListesi, title: listx[i].TurAile };
          list.push(y);
        }
        this.list =list;
        this.loading = false;
      });
    } 
  }

此处是屏幕代码

const { TurListesiStore } = this.props;
 <SectionList
                keyExtractor={(item, index) => item.id}
                renderItem={({ item, index }) => {
                  return (
                    <SectionListItem
                      item={item}
                      index={index}
                    ></SectionListItem>
                  );
                }}
                renderSectionHeader={({ section }) => {
                  return <SectionHeader section={section} />;
                }}
                sections={TurListesiStore.list}
              />

Answer 1

尝试：

let list = [];
for (let idx in listx) {
  list.push({ data: listx[idx].TurListesi, title: listx[idx].TurAile });
}

在javascript数组中，不一定在所有索引上都填充要理解的例子：

var myArray = [0,1,2,3]

console.log(' 1) myArray.length', myArray.length )                          // -->  4

myArray[6] = 6 

console.log(' 2) myArray.length', myArray.length )                           // -->  7
console.log(' 2) Object.keys(myArray).length', Object.keys(myArray).length ) // -->  5

myArray[-4] = 99 

console.log(' 3) myArray.length', myArray.length )                           // -->  7 again
console.log(' 3) Object.keys(myArray).length', Object.keys(myArray).length ) // -->  6


Object.keys(myArray).length

console.log(' myArray[-4]', myArray[-4] )                                    // -->  99

let r1 = ''
for(let i=0;i<myArray.length; i++) {
  r1 += ' '+i+'->'+myArray[i]
}
console.log(r1 )               //  0->0   1->1  2->2   3->3   4->undefined   5->undefined   6->6

let r2 = ''
for(let idx in myArray) {
  r2 += ' '+idx+'->'+myArray[idx]
}
console.log(r2 )               //  0->0   1->1  2->2   3->3  6->6  -4->99

.as-console {background-color:black !important; color:lime;}
.as-console-wrapper {min-height:100% !important; top:0;}