读jQuery之九 一些瑕疵说明

1，bind 方法，最后一个参数fn是多余的

// Handle object literals 
if ( typeof type === "object" ) { 
for ( var key in type ) { 
this[ name ](key, data, type[key], fn); 
} 
return this; 
}

2，注释

// Add which for click: 1 === left; 2 === middle; 3 === right

应修改为

// Add which for mousedown/mouseup : 1 === left; 2 === middle; 3 === right

3，data方法，定义了局部变量internalKey，但后续代码仍然沿用jQuery.expando。

var internalKey = jQuery.expando, getByName = typeof name === "string", thisCache,

4，jQuery.event.add方法，arguments改为e，apply改为call 更好一些。因为只会传一个参数：事件对象。

elemData.handle = eventHandle = function( e ) { 
// Discard the second event of a jQuery.event.trigger() and 
// when an event is called after a page has unloaded 
return typeof jQuery !== "undefined" && (!e || jQuery.event.triggered !== e.type) ? 
jQuery.event.handle.apply( eventHandle.elem, arguments ) : 
undefined; };

5，基于 “勿重复检测浏览器” 原则，jQuery.event.add 以下代码

if ( elem.addEventListener ) { 
elem.addEventListener( type, eventHandle, false ); } else if ( elem.attachEvent ) { 
elem.attachEvent( "on" + type, eventHandle ); 
}

应该使用以下来替换

jQuery.addEvent = document.addEventListener ? 
function( elem, type, handle ) { 
if ( elem.addEventListener ) { 
elem.addEventListener( type, handle, false ); 
} 
} : 
function( elem, type, handle ) { 
if ( elem.attactEvent ) { 
elem.attactEvent( "on" + type, handle ); 
} 
};

事实上，jQuery中已经有了jQuery.removeEvent，却不知为何没有jQuery.addEvent。