js取得指定のクッキーの具体的な実現

 
  
var cookieName = "cookie  "; 
  
var cookieValue = null;//  cookie value  
  
if (document.cookie && document.cookie != '') { 
  
var cookies = document.cookie.split(';');//      cookie      
  
for (var i = 0; i < cookies.length; i++) { 
  
var cookie = cookies[i];//      cookies   
  
if (cookie.substring(0, cookieName.length + 2).trim() == cookieName.trim() + "=") {//     cookie    cookie      
  
cookieValue = cookie.substring(cookieName.length + 2, cookie.length); 
  
break 
  
} 
  
} 
  
} 
  
if (cookieValue != "" && cookieValue != null) {//       cookie  
  
alert(cookieValue); 
  
} else {//  cookie     
  
alert("not cookie!!!"); 
  
} 
  
 
 

 
  
//     
  
String.prototype.trim = function () { 
  
return this.replace(new RegExp("(^[\\s]*)|([\\s]*$)", "g"), ""); 
  
}