我在我的项目中使用过，对我来说非常适合

var returnObjName= JSON.parse(localStorage.getItem('ObjName'));
if(returnObjName && Object.keys(returnObjName).length > 0){
   //Exist data in local storage
}else{
  //Non Exist data block
}

localStorage['root2']=null;

localStorage.getItem("root2") === null //false

也许最好先看一遍计划?

localStorage['root1']=187;
187
'root1' in localStorage
true

为真正的

localStorage.infiniteScrollEnabled = 1;

因为假

localStorage.removeItem("infiniteScrollEnabled")

检查存在

if (localStorage[""infiniteScrollEnabled""]) {
  //CODE IF ENABLED
}

您应该在localStorage中检查项目的类型

if(localStorage.token !== null) {
   // this will only work if the token is set in the localStorage
}

if(typeof localStorage.token !== 'undefined') {
  // do something with token
}

if(typeof localStorage.token === 'undefined') {
  // token doesn't exist in the localStorage, maybe set it?
}

试试这段代码

if (localStorage.getItem("infiniteScrollEnabled") === null) {

} else {

}

我在这里添加了一些方法来检查

方法1

if("infiniteScrollEnabled" in localStorage){
     console.log("Item exists in localstorage");
}else{
    console.log("Item does not exist in localstoarge";
}

方法2

if(localStorage.getItem("infiniteScrollEnabled") === null){
    console.log("Item does not exist in localstoarge";
}else{
   console.log("Item exists in localstorage");
}

方法3

if(typeof localStorage["cart"] === "undefined"){
    console.log("Item does not exist in localstoarge";
}else{
   console.log("Item exists in localstorage");
}

方法4

if(localStorage.hasOwnProperty("infiniteScrollEnabled")){
     console.log("Item exists in localstorage");
 }else{
    console.log("Item does not exist in localstoarge";
 }