我如何检查一个项目是否设置在localStorage?目前我正在使用
if (!(localStorage.getItem("infiniteScrollEnabled") == true || localStorage.getItem("infiniteScrollEnabled") == false)) {
// init variable/set default variable for item
localStorage.setItem("infiniteScrollEnabled", true);
}
当前回答
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?
}
其他回答
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?
}
为真正的
localStorage.infiniteScrollEnabled = 1;
因为假
localStorage.removeItem("infiniteScrollEnabled")
检查存在
if (localStorage[""infiniteScrollEnabled""]) {
//CODE IF ENABLED
}
可以尝试这样做:
let x = localStorage.getItem('infiniteScrollEnabled') === null ? "not found" : localStorage.getItem('infiniteScrollEnabled')
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
最短的方法是使用默认值，如果key不在存储中:
var sValue = localStorage['my.token'] || ''; /* for strings */
var iValue = localStorage['my.token'] || 0; /* for integers */
