In my usual process of developing web pages, it may involve local storage of the browser. The current mainstream browser storage methods include: cookies, direct reading of xml, userData, H5 LocalStorage, etc. Cookies store data is limited, but It is more convenient to operate when the amount of data is not large.
The following example is mainly to pop up a prompt box when the web page is opened, but the prompt box will not be displayed when the web page is refreshed after the second time. Of course, the cookie time can be flexibly set to control whether to display the prompt box.
<!DOCTYPE html>
<html>
<head lang="en">
<meta charset="UTF-8">
<title></title>
</head>
<body>
<script>
var cookie = {
setCookie:function(name,value,iDay){
var cookieStr = '';
if(iDay == undefined){
cookieStr += name+'='+value+';';
}else{
var oDate = new Date();
oDate.setDate(oDate.getDate()+iDay);
cookieStr += name+'='+value+';express='+oDate;
}
document.cookie = cookieStr;
},
getCookie:function(name){
var arr = document.cookie.split(';');
for(var i=0;i<arr.length;i++){
var arr2 = arr[i].split('=');
if(arr2[0] == name){
return arr2[1];
}
}
return '';
},
removeCookie:function(name){
this.setCookie(name,'1',-1);
}
}
function ControlAlert(){
var flag = cookie.getCookie('flag');
if(!flag){
alert("我是第一次加载的哟！");
cookie.setCookie('flag',true);
//cookie.setCookie('flag',true,1);//如果有第三个参数则保存cookie的天数，如果不设置，浏览器关闭时cookie过期
}
}
(function(){
ControlAlert();
}());
</script>
</body>
</html>
The above are the related operations of cookied. I hope it will be helpful to everyone's learning.
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