javascript operation Cookie (set read delete) method

Cookie is a way for clients to store data, which can be used to maintain state.

1. Set Cookie:

a. No expiration time :(if you do not set the expiration time, the default is session-level Cookie, and the browser will be disabled if closed)

function setCookie(name,value) {

    document.cookie = name + '=' + escape(value);

}

b. Fixed expiration time:

function setCookie(name,value)

{

    var Days = 30;

    var exp = new Date();

    exp.setTime(exp.getTime() + Days*24*60*60*1000);

    document.cookie = name + "="+ escape (value) + ";expires=" + exp.toGMTString();

} 

c. Custom expiration time:

// Set a custom expiration time cookie

function setCookie(name,value,time)

{

    var msec = getMsec(time); // For ms 

    var exp = new Date();

    exp.setTime(exp.getTime() + msec*1);

    document.cookie = name + "="+ escape (value) + ";expires=" + exp.toGMTString();

}

// Converts the string time to milliseconds ,1 seconds =1000 ms 

function getMsec(DateStr)

{

   var timeNum=str.substring(0,str.length-1)*1; // Number of time 

   var timeStr=str.substring(str.length-1,str.length); // Time unit prefix, such as h Said hours 

   

   if (timeStr=="s") //20s said 20 seconds 

   {

        return timeNum*1000;

   }

   else if (timeStr=="h") //12h said 12 hours 

   {

       return timeNum*60*60*1000;

   }

   else if (timeStr=="d")

   {

       return timeNum*24*60*60*1000; //30d said 30 day 

   }

}

2. Read Cookie:

function getCookie(name)

{

    var arr,reg=new RegExp("(^| )"+name+"=([^;]*)(;|$)"); // Regular match 

    if(arr=document.cookie.match(reg)){

      return unescape(arr[2]);

    }

    else{

     return null;

    }

} 

3. Delete Cookie:

function delCookie(name)

{

    var exp = new Date();

    exp.setTime(exp.getTime() - 1);

    var cval=getCookie(name);

    if(cval!=null){

      document.cookie= name + "="+cval+";expires="+exp.toGMTString();

    }

} 

4. Call example:

setCookie("name","hayden");

alert(getCookie("name")); 

The above is the article about javascript operation cookie all content, hope to be able to help you learn javascript.