jquery禁用右键、文本选择功能、复制按键的实现

 //禁用右键、文本选择功能、复制按键  
    $(document).bind("contextmenu",function(){return false;});  
    $(document).bind("selectstart",function(){return false;});  
    $(document).keydown(function(){return key(arguments[0])});  
      
    //按键时提示警告  
    function key(e){  
    var keynum;  
    if(window.event){  
    keynum = e.keyCode; // IE  
    }else if(e.which){  
    keynum = e.which; // Netscape/Firefox/Opera  
    }  
    if(keynum == 17){  
    alert("禁止复制内容！");  
    return false;  
    }  
    }  
      
    //禁用右键、文本选择功能、复制按键  
        $(document).bind("contextmenu",function(){return false;});  
        $(document).bind("selectstart",function(){return false;});  
        $(document).keydown(function(){return key(arguments[0])});   
       
     //按键时提示警告  
           function key(e){  
                var keynum;  
                if(window.event) // IE  
                  {  
                    keynum = e.keyCode;  
                  }  
                else if(e.which) // Netscape/Firefox/Opera  
                  {  
                    keynum = e.which;  
                  }  
                if(keynum == 17){ alert("禁止复制内容！");return false;}  
            }  
      
        
    //屏蔽鼠标右键、Ctrl+N、Shift+F10、F11、F5刷新、退格键       
    function   document.oncontextmenu(){event.returnValue=false;}//屏蔽鼠标右键     
    function   window.onhelp(){return false}       //屏蔽F1帮助     
    function   document.onkeydown(){     
        if((window.event.altKey)&&     
          ((window.event.keyCode==37)||            //屏蔽Alt+方向键←     
          (window.event.keyCode==39))){            //屏蔽Alt+方向键→  
               alert("不准你使用ALT+方向键前进或后退网页！");     
               event.returnValue=false;      
          }         if((event.keyCode==8)||                    //屏蔽退格删除键      
          (event.keyCode==116)||                   //屏蔽F5刷新键     
          (event.ctrlKey && event.keyCode==82)){   //Ctrl+R     
               event.keyCode=0;     
               event.returnValue=false;     
          }     
          if(event.keyCode==122){event.keyCode=0;event.returnValue=false;}    //屏蔽F11     
          if(event.ctrlKey && event.keyCode==78)event.returnValue=false;      //屏蔽Ctrl+n     
          if(event.shiftKey && event.keyCode==121)event.returnValue=false;    //屏蔽shift+F10     
          if(window.event.srcElement.tagName=="A" && window.event.shiftKey)       
             window.event.returnValue=false;       //屏蔽shift加鼠标左键新开一网页     
          if((window.event.altKey)&&(window.event.keyCode==115)){             //屏蔽Alt+F4      
             window.showModelessDialog("about:blank","","dialogWidth:1px;dialogheight:1px");     
             return false;     
          }     
      }