HTM 网页  

  <META   HTTP-EQUIV="pragma"   CONTENT="no-cache"> 

  <META   HTTP-EQUIV="Cache-Control"   CONTENT="no-cache,   must-revalidate"> 

  <META   HTTP-EQUIV="expires"   CONTENT="Wed,   26   Feb   1997   08:21:57   GMT"> 

  ASP 网页  

  <% 

      Response.Expires   =   -1 

      Response.ExpiresAbsolute   =   Now()   -   1 

      Response.cachecontrol   =   "no-cache" 

  %> 

  PHP 网页  

  header("Expires:   Mon,   26   Jul   1997   05:00:00   GMT"); 

  header("Cache-Control:   no-cache,   must-revalidate"); 

  header("Pragma:   no-cache"); 

  JSP 

          response.setHeader("Pragma","No-Cache"); 

          response.setHeader("Cache-Control","No-Cache"); 

          response.setDateHeader("Expires",   0); 

  C# 中禁止 cache 的方法！  

  Response.Buffer=true; 

  Response.ExpiresAbsolute=System.DateTime.Now.AddSeconds(-1); 

  Response.Expires=0; 

  Response.CacheControl="no-cache"; 

禁止图片缓存：

在图片后面加一个随机参数，如：

<img src=”images/bg.gif?temp_id=156404/>

经测试，有效。

// 提前写好的JavaScript Class定义和继承
// 当然，这种代码很丑陋，散发着代码的坏味道。
function BaseClass() {
    //BaseClass constructor code goes here 
}

BaseClass.prototype.getName = function() {
    return "BaseClass";
}

function SubClass() {
    //SubClass constructor code goes here 
}

//Inherit the methods of BaseClass
SubClass.prototype = new BaseClass();

//Override the parent's getName method
SubClass.prototype.getName = function() {
    return "SubClass";
}

//Alerts "SubClass"
alert(new SubClass().getName());

// 运行时的JavaScript Class 定义和继承
// 看上去很传统，但这些脚本会导致在Internet Explorer中的内存泄漏.
function BaseClass() {
    this.getName = function() {
        return "BaseClass";
    };    

    //BaseClass constructor code goes here 
}

function SubClass() {
    //在对象实例建立时重载父类的getName方法 
    this.getName = function() {
        return "SubClass";
    }

    //SubClass constructor code goes here 
}

//Inherit the methods of BaseClass
SubClass.prototype = new BaseClass();

//Alerts "SubClass"
alert(new SubClass().getName());

function BaseClass() { }
BaseClass.prototype.getName = function() {
    return "BaseClass(" + this.getId() + ")";
}

BaseClass.prototype.getId = function() {
    return 1;
}

function SubClass() {}
SubClass.prototype = new BaseClass();
SubClass.prototype.getName = function() {
    //调用父类的getName()方法
    //哈哈，这是对父类调用的直接引用吗？
    return "SubClass(" + this.getId() + ") extends " +
        BaseClass.prototype.getName();
}

SubClass.prototype.getId = function() {
    return 2;
}

//输出结果："SubClass(2) extends BaseClass(1)";
//这是正确的输出吗?
alert(new SubClass().getName());

function BaseClass() { }
BaseClass.prototype.getName = function() {
    return "BaseClass(" + this.getId() + ")";
}

BaseClass.prototype.getId = function() {
    return 1;
}

function SubClass() {}
SubClass.prototype = new BaseClass();
SubClass.prototype.getName = function() {
    //一点魔法加上多态性！
    //但很明显，这还是一个直接引用!    
    return "SubClass(" + this.getId() + ") extends " +
        BaseClass.prototype.getName.call(this);
}

SubClass.prototype.getId = function() {
    return 2;
}

//输出结果："SubClass(2) extends BaseClass(2)";
//Hey, 我们得到了正确的输出!
alert(new SubClass().getName());

//Crockford的方法：给所有的function都增加'inherits' 方法、
//每个类都增加了'uber'方法来调用父类方法
Function.prototype.inherits = function(parent) {
    var d = 0, p = (this.prototype = new parent());
    
    this.prototype.uber = function(name) {
        var f, r, t = d, v = parent.prototype;
        if (t) {
            while (t) {
                v = v.constructor.prototype;
                t -= 1;
            }
            f = v[name];
        } else {
            f = p[name];
            if (f == this[name]) {
                f = v[name];
            }
        }
        d += 1;
        r = f.apply(this, Array.prototype.slice.apply(arguments, [1]));
        d -= 1;
        return r;
    };
};

function BaseClass() { }
BaseClass.prototype.getName = function() {
    return "BaseClass(" + this.getId() + ")";
}

BaseClass.prototype.getId = function() {
    return 1;
}

function SubClass() {}
SubClass.inherits(BaseClass);
SubClass.prototype.getName = function() {
    //这里看上去非常的清晰，它调用了BaseClass的getName()方法
return "SubClass(" + this.getId() + ") extends " +
        this.uber("getName");
}

SubClass.prototype.getId = function() {
    return 2;
}

function TopClass() {}
TopClass.inherits(SubClass);
TopClass.prototype.getName = function() {
    //这里看上去非常的清晰，它调用了SubClass的getName()方法
    return "TopClass(" + this.getId() + ") extends " +
        this.uber("getName");
}

TopClass.prototype.getId = function() {
    //Ok, 因此this.getId()应该总是
//返回调用SubClass的getId()方法的返回值（2）。
    return this.uber("getId");
}

//输出结果："TopClass(2) extends SubClass(1) extends BaseClass(1)"
//嗯？后面的两次this.getId()调用都没有返回2.
//发生了什么？ 
alert(new TopClass().getName());

//定义最顶级类
function Class() { }
Class.prototype.construct = function() {};
Class.__asMethod__ = function(func, superClass) {    
    return function() {
        var currentSuperClass = this.$;
        this.$ = superClass;
        var ret = func.apply(this, arguments);        
        this.$ = currentSuperClass;
        return ret;
    };
};

Class.extend = function(def) {
    var classDef = function() {
        if (arguments[0] !== Class) { this.construct.apply(this, arguments); }
    };
    
    var proto = new this(Class);
    var superClass = this.prototype;
    
    for (var n in def) {
        var item = def[n];                        
        
        if (item instanceof Function) {
            item = Class.__asMethod__(item, superClass);
        }
        
        proto[n] = item;
    }

    proto.$ = superClass;
    classDef.prototype = proto;
    
    //赋给这个新的子类同样的静态extend方法
    classDef.extend = this.extend;        
    return classDef;
};

//Hey, 注意一下这个类的定义方式
//看上去比其它方式要清楚些
var BaseClass = Class.extend({
    construct: function() { /* optional constructor method */ },
    
    getName: function() {
        return "BaseClass(" + this.getId() + ")";
    },
    
    getId: function() {
        return 1;
    }
});

var SubClass = BaseClass.extend({
    getName: function() {
        //调用BaseClass的getName()方法
        return "SubClass(" + this.getId() + ") extends " +
            this.$.getName.call(this);
    },
    
    getId: function() {
        return 2;
    }
});

var TopClass = SubClass.extend({
    getName: function() {
        //调用SubClass的getName()方法
        return "TopClass(" + this.getId() + ") extends " +
            this.$.getName.call(this);
    },
    
    getId: function() {
        //this.getId()总是返回调用父类的getId()方法的返回值（2）
        return this.$.getId.call(this);
    }
});

//输出结果："TopClass(2) extends SubClass(2) extends BaseClass(2)"
//一切都正确!
alert(new TopClass().getName());

//定义最顶级类
function Class() { }
Class.prototype.construct = function() {};
Class.extend = function(def) {
    var classDef = function() {
        if (arguments[0] !== Class) { this.construct.apply(this, arguments); }
    };
    
    var proto = new this(Class);
    var superClass = this.prototype;
    
    for (var n in def) {
        var item = def[n];                        
        if (item instanceof Function) item.$ = superClass;
        proto[n] = item;
    }

    classDef.prototype = proto;
    
    //赋给这个新的子类同样的静态extend方法 
    classDef.extend = this.extend;        
    return classDef;
};

//Hey, 注意一下这个类的定义方式
//看上去比其它方式要清楚些
var BaseClass = Class.extend({
    construct: function() { /* optional constructor method */ },
        
    getName: function() {
        return "BaseClass(" + this.getId() + ")";
    },
    
    getId: function() {
        return 1;
    }
});

var SubClass = BaseClass.extend({
    getName: function() {
        //调用BaseClass的getName()方法
        return "SubClass(" + this.getId() + ") extends " +
            arguments.callee.$.getName.call(this);
    },
    
    getId: function() {
        return 2;
    }
});

var TopClass = SubClass.extend({
    getName: function() {
        //调用SubClass的getName()方法
        return "TopClass(" + this.getId() + ") extends " +
            arguments.callee.$.getName.call(this);
    },
    
    getId: function() {
        // this.getId()总是返回调用父类的getId()方法的返回值（2） 
        return arguments.callee.$.getId.call(this);
    }
});

//输出结果："TopClass(2) extends SubClass(2) extends BaseClass(2)"
//工作正常！而且没有任何中间function
alert(new TopClass().getName());

function XmlReader()
{
 this.xmlDoc=null;
 this.createXmlDoc=getXmlDoc;
 this.close=closeXmlDoc;
}
function getXmlDoc()
{
 if (window.ActiveXObject)
  {
    //document.write("Microsoft.XMLDOM");
   this.xmlDoc = new ActiveXObject("Microsoft.XMLDOM");
  }
  else if (document.implementation && document.implementation.createDocument)
  {
   //document.write("document.implementation.createDocument");
   this.xmlDoc= document.implementation.createDocument("","doc",null);
  }
  if (typeof this.xmlDoc!="undefined")
  {
   return this.xmlDoc;
  }else{
   return null;
  }
}
function closeXmlDoc()
{
 this.xmlDoc=null
}
   

<script language='javascript'>
function showitem(itemname,itemsrc,itemtype)
{
 this.itemname=itemname;
 this.itemsrc=itemsrc;
 this.itemtype=itemtype;
 
 this.play=showplay;
}
function showplay()
{
 if(this.itemtype=='img'){
  
 }else{
 
 }
}
function itemlist(){
this.item1=new showitem("item1","1.gif","img");
this.item2=new showitem("item2","pixviewer.swf","fla");
this.item3=new showitem("item3","2.gif","img");
this.item4=new showitem("item4","1.gif","img");
this.item5=new showitem("item5","2.gif","img");
this.size=5;
}

var mylist=new itemlist();
mysize=mylist.size;
count=1;

function change_item()
{
var myitem = mylist['item'+count];
var preitem ;
if(count>1){
 preitem = mylist['item'+(count-1)];
}else{
 preitem = mylist['item'+count];
}

if(myitem.itemtype=='img'){
 document.all('picdiv').style.backgroundImage='url('+preitem.itemsrc+')';
 
 document.pic.src=myitem.itemsrc;
 document.all('picdiv').style.display='';
 document.all('fladiv').style.display='none';

 pic.filters.revealTrans.Transition=6;
 pic.filters.item(0).apply()
 pic.style.visibility='visible'
 pic.filters.item(0).play()
 setTimeout("pic.style.visibility='hidden'",2000);
}else{ 
 document.all('fladiv').style.backgroundImage='url('+preitem.itemsrc+')';
 
 document.all('picdiv').style.display='none';
 document.all('fladiv').style.display='';
 
}
count++;
if(count>mysize) count=1
tt=setTimeout('change_item()',2000)
}

</script>

</head>
<body onload="change_item();">
<table width="120" height="90"><tr><td>
<div id="picdiv" name="picdiv" width="120" height="90">
 <img src='1.gif' id="pic" name="pic" width="120" height="90"  style='visibility:hidden;filter:revealtrans(duration=2.0,transition=0)'>
 
</div>
<div id="fladiv" name="fladiv" style="display:''" width="120" height="90">
<object classid='clsid:D27CDB6E-AE6D-11cf-96B8-444553540000' codebase='/swflash.cab#version=6,0,0,0' width='120' height='90'>

        <param name=movie value='pixviewer.swf'>

        <param name=quality value=high>

        <embed src='pixviewer.swf' quality=high pluginspage=http://www.macromedia.com/shockwave/download/index.cgi?P1_Prod_Version=ShockwaveFlash type=application/x-shockwave-flash width='120' height='90'>

        </embed>

</object>
</div>
</td>
</tr>
</table>

</body>
</html>