JS set cookies, delete cookies

The first type: (This is the Code of the website)

 <script>//settings cookiefunction setcookie (CNAME, cvalue, exdays) {var d = new Date ();    D.settime (D.gettime () + (exdays*24*60*60*1000));    var expires = "expires=" +d.toutcstring (); Document.cookie = cname + "=" + Cvalue + ";" + Expires;}    Get cookiefunction GetCookie (CNAME) {var name = cname + "=";    var ca = Document.cookie.split (';');        for (var i=0; i<ca.length; i++) {var c = ca[i];        while (C.charat (0) = = ") c = c.substring (1);    if (C.indexof (name)! =-1) return c.substring (Name.length, c.length); } return "";}  Clear Cookie function ClearCookie (name) {Setcookie (name, "",-1);    } function Checkcookie () {var user = GetCookie ("username");    if (User! = "") {alert ("Welcome again" + user);        } else {user = prompt ("Please enter your name:", "" ");        if (User! = "" "&& user! = null) {Setcookie (" username ", user, 365); }}}checkcookie (); </script> 

The second type:

<script>//js operation Cookie Method!//write Cookiesfunction Setcookie (c_name, value, expiredays) {var exdate=new Date ();　　　　Exdate.setdate (exdate.getdate () + expiredays); Document.cookie=c_name+ "=" + Escape (value) + ((expiredays==null)? 　　"": "; expires=" +exdate.togmtstring ()); }//Read cookiesfunction GetCookie (name) {    var arr,reg=new RegExp ("(^|)" +name+ "= ([^;] *)(;|$)");     if (Arr=document.cookie.match (reg))         return (arr[2]);    else        return null;} Delete cookiesfunction 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 ();} Use example Setcookie (' username ', ' Darren ', ') alert (GetCookie ("username"));</script>

A third example

Attention:
The Chrome browser does not get cookies locally. Must be available on the server. If it is local, you can put it under the WWW directory.
Google Chrome only supports the reading and writing of cookies on online websites, which is forbidden for local HTML cookie operations. So the following code if you write in a local HTML file, will pop up the dialog box content is empty.
Document.cookie = "Test=cooo";
alert (Document.cookie);
If this page is the content of the online website, the cookie content test=cooo and so on will be displayed normally.
JS set cookies, delete cookies