Javascript: javascript cookie settings

This codes set and gets cookies and also, if cookies are not set in the browser, it shows a page to warn member.

function 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()); if (document.cookie.length<=0)     location="jscookietest.php?cookie=0"; } function getCookie(c_name) { if (document.cookie.length>0)   {   c_start=document.cookie.indexOf(c_name + "=");   if (c_start!=-1)     {     c_start=c_start + c_name.length+1;     c_end=document.cookie.indexOf(";",c_start);     if (c_end==-1) c_end=document.cookie.length;     return unescape(document.cookie.substring(c_start,c_end));     }   } return ""; } function issetCookie(c_name) { value=getCookie(c_name); if (value!=null && value!="") {     return 1; } else {     return 0; } } function deleteCookie ( cookie_name ) {   var cookie_date = new Date ( );  // current date & time   cookie_date.setTime ( cookie_date.getTime() - 1 );   document.cookie = cookie_name += "=; expires=" + cookie_date.toGMTString(); }