jquery/src/attributes.js

// exclude the following css properties to add px
var exclude = /z-?index|font-?weight|opacity|zoom|line-?height/i,
	// cache defaultView
	defaultView = document.defaultView || {};

jQuery.fn.extend({
	attr: function( name, value, type ) {
		var options = name, isFunction = jQuery.isFunction( value );

		// Look for the case where we're accessing a style value
		if ( typeof name === "string" ) {
			if ( value === undefined ) {
				return this.length ?
					jQuery[ type || "attr" ]( this[0], name ) :
					null;

			} else {
				options = {};
				options[ name ] = value;
			}
		}

		// Check to see if we're setting style values
		for ( var i = 0, l = this.length; i < l; i++ ) {
			var elem = this[i];

			// Set all the styles
			for ( var prop in options ) {
				value = options[prop];

				if ( isFunction ) {
					value = value.call( elem, i );
				}

				if ( typeof value === "number" && type === "curCSS" && !exclude.test(prop) ) {
					value = value + "px";
				}

				jQuery.attr( type ? elem.style : elem, prop, value );
			}
		}

		return this;
	},

	css: function( key, value ) {
		// ignore negative width and height values
		if ( (key == 'width' || key == 'height') && parseFloat(value) < 0 )
			value = undefined;
		return this.attr( key, value, "curCSS" );
	},

	hasClass: function( selector ) {
		return !!selector && this.is( "." + selector );
	},

	val: function( value ) {
		if ( value === undefined ) {
			var elem = this[0];

			if ( elem ) {
				if( jQuery.nodeName( elem, 'option' ) )
					return (elem.attributes.value || {}).specified ? elem.value : elem.text;
				
				// We need to handle select boxes special
				if ( jQuery.nodeName( elem, "select" ) ) {
					var index = elem.selectedIndex,
						values = [],
						options = elem.options,
						one = elem.type == "select-one";

					// Nothing was selected
					if ( index < 0 )
						return null;

					// Loop through all the selected options
					for ( var i = one ? index : 0, max = one ? index + 1 : options.length; i < max; i++ ) {
						var option = options[ i ];

						if ( option.selected ) {
							// Get the specifc value for the option
							value = jQuery(option).val();

							// We don't need an array for one selects
							if ( one )
								return value;

							// Multi-Selects return an array
							values.push( value );
						}
					}

					return values;				
				}

				// Everything else, we just grab the value
				return (elem.value || "").replace(/\r/g, "");

			}

			return undefined;
		}

		if ( typeof value === "number" )
			value += '';

		return this.each(function(){
			if ( this.nodeType != 1 )
				return;

			if ( jQuery.isArray(value) && /radio|checkbox/.test( this.type ) )
				this.checked = (jQuery.inArray(this.value, value) >= 0 ||
					jQuery.inArray(this.name, value) >= 0);

			else if ( jQuery.nodeName( this, "select" ) ) {
				var values = jQuery.makeArray(value);

				jQuery( "option", this ).each(function(){
					this.selected = (jQuery.inArray( this.value, values ) >= 0 ||
						jQuery.inArray( this.text, values ) >= 0);
				});

				if ( !values.length )
					this.selectedIndex = -1;

			} else
				this.value = value;
		});
	}
});

jQuery.each({
	removeAttr: function( name ) {
		jQuery.attr( this, name, "" );
		if (this.nodeType == 1)
			this.removeAttribute( name );
	},

	addClass: function( classNames ) {
		jQuery.className.add( this, classNames );
	},

	removeClass: function( classNames ) {
		jQuery.className.remove( this, classNames );
	},

	toggleClass: function( classNames, state ) {
		if( typeof state !== "boolean" )
			state = !jQuery.className.has( this, classNames );
		jQuery.className[ state ? "add" : "remove" ]( this, classNames );
	}
}, function(name, fn){
	jQuery.fn[ name ] = function(){
		return this.each( fn, arguments );
	};
});

jQuery.extend({
	className: {
		// internal only, use addClass("class")
		add: function( elem, classNames ) {
			jQuery.each((classNames || "").split(/\s+/), function(i, className){
				if ( elem.nodeType == 1 && !jQuery.className.has( elem.className, className ) )
					elem.className += (elem.className ? " " : "") + className;
			});
		},

		// internal only, use removeClass("class")
		remove: function( elem, classNames ) {
			if (elem.nodeType == 1)
				elem.className = classNames !== undefined ?
					jQuery.grep(elem.className.split(/\s+/), function(className){
						return !jQuery.className.has( classNames, className );
					}).join(" ") :
					"";
		},

		// internal only, use hasClass("class")
		has: function( elem, className ) {
			return elem && jQuery.inArray( className, (elem.className || elem).toString().split(/\s+/) ) > -1;
		}
	},

	// A method for quickly swapping in/out CSS properties to get correct calculations
	swap: function( elem, options, callback ) {
		var old = {};
		// Remember the old values, and insert the new ones
		for ( var name in options ) {
			old[ name ] = elem.style[ name ];
			elem.style[ name ] = options[ name ];
		}

		callback.call( elem );

		// Revert the old values
		for ( var name in options )
			elem.style[ name ] = old[ name ];
	},

	css: function( elem, name, force, extra ) {
		if ( name == "width" || name == "height" ) {
			var val, props = { position: "absolute", visibility: "hidden", display:"block" }, which = name == "width" ? [ "Left", "Right" ] : [ "Top", "Bottom" ];

			function getWH() {
				val = name == "width" ? elem.offsetWidth : elem.offsetHeight;

				if ( extra === "border" )
					return;

				jQuery.each( which, function() {
					if ( !extra )
						val -= parseFloat(jQuery.curCSS( elem, "padding" + this, true)) || 0;
					if ( extra === "margin" )
						val += parseFloat(jQuery.curCSS( elem, "margin" + this, true)) || 0;
					else
						val -= parseFloat(jQuery.curCSS( elem, "border" + this + "Width", true)) || 0;
				});
			}

			if ( elem.offsetWidth !== 0 )
				getWH();
			else
				jQuery.swap( elem, props, getWH );

			return Math.max(0, Math.round(val));
		}

		return jQuery.curCSS( elem, name, force );
	},

	curCSS: function( elem, name, force ) {
		var ret, style = elem.style;

		// We need to handle opacity special in IE
		if ( name == "opacity" && !jQuery.support.opacity ) {
			ret = jQuery.attr( style, "opacity" );

			return ret == "" ?
				"1" :
				ret;
		}

		// Make sure we're using the right name for getting the float value
		if ( name.match( /float/i ) )
			name = styleFloat;

		if ( !force && style && style[ name ] )
			ret = style[ name ];

		else if ( defaultView.getComputedStyle ) {

			// Only "float" is needed here
			if ( name.match( /float/i ) )
				name = "float";

			name = name.replace( /([A-Z])/g, "-$1" ).toLowerCase();

			var computedStyle = defaultView.getComputedStyle( elem, null );

			if ( computedStyle )
				ret = computedStyle.getPropertyValue( name );

			// We should always get a number back from opacity
			if ( name == "opacity" && ret == "" )
				ret = "1";

		} else if ( elem.currentStyle ) {
			var camelCase = name.replace(/\-(\w)/g, function(all, letter){
				return letter.toUpperCase();
			});

			ret = elem.currentStyle[ name ] || elem.currentStyle[ camelCase ];

			// From the awesome hack by Dean Edwards
			// http://erik.eae.net/archives/2007/07/27/18.54.15/#comment-102291

			// If we're not dealing with a regular pixel number
			// but a number that has a weird ending, we need to convert it to pixels
			if ( !/^\d+(px)?$/i.test( ret ) && /^\d/.test( ret ) ) {
				// Remember the original values
				var left = style.left, rsLeft = elem.runtimeStyle.left;

				// Put in the new values to get a computed value out
				elem.runtimeStyle.left = elem.currentStyle.left;
				style.left = ret || 0;
				ret = style.pixelLeft + "px";

				// Revert the changed values
				style.left = left;
				elem.runtimeStyle.left = rsLeft;
			}
		}

		return ret;
	},

	attr: function( elem, name, value ) {
		// don't set attributes on text and comment nodes
		if (!elem || elem.nodeType == 3 || elem.nodeType == 8)
			return undefined;

		var notxml = !elem.tagName || !jQuery.isXMLDoc( elem ),
			// Whether we are setting (or getting)
			set = value !== undefined;

		// Try to normalize/fix the name
		name = notxml && jQuery.props[ name ] || name;

		// Only do all the following if this is a node (faster for style)
		// IE elem.getAttribute passes even for style
		if ( elem.tagName ) {

			// These attributes require special treatment
			var special = /href|src|style/.test( name );

			// Safari mis-reports the default selected property of a hidden option
			// Accessing the parent's selectedIndex property fixes it
			if ( name == "selected" && elem.parentNode )
				elem.parentNode.selectedIndex;

			// If applicable, access the attribute via the DOM 0 way
			if ( name in elem && notxml && !special ) {
				if ( set ){
					// We can't allow the type property to be changed (since it causes problems in IE)
					if ( name == "type" && elem.nodeName.match(/(button|input)/i) && elem.parentNode )
						throw "type property can't be changed";

					elem[ name ] = value;
				}

				// browsers index elements by id/name on forms, give priority to attributes.
				if( jQuery.nodeName( elem, "form" ) && elem.getAttributeNode(name) )
					return elem.getAttributeNode( name ).nodeValue;

				// elem.tabIndex doesn't always return the correct value when it hasn't been explicitly set
				// http://fluidproject.org/blog/2008/01/09/getting-setting-and-removing-tabindex-values-with-javascript/
				if ( name == "tabIndex" ) {
					var attributeNode = elem.getAttributeNode( "tabIndex" );
					return attributeNode && attributeNode.specified
						? attributeNode.value
						: elem.nodeName.match(/(button|input|object|select|textarea)/i)
							? 0
							: elem.nodeName.match(/^(a|area)$/i) && elem.href
								? 0
								: undefined;
				}

				return elem[ name ];
			}

			if ( !jQuery.support.style && notxml &&  name == "style" )
				return jQuery.attr( elem.style, "cssText", value );

			if ( set )
				// convert the value to a string (all browsers do this but IE) see #1070
				elem.setAttribute( name, "" + value );

			var attr = !jQuery.support.hrefNormalized && notxml && special
					// Some attributes require a special call on IE
					? elem.getAttribute( name, 2 )
					: elem.getAttribute( name );

			// Non-existent attributes return null, we normalize to undefined
			return attr === null ? undefined : attr;
		}

		// elem is actually elem.style ... set the style

		// IE uses filters for opacity
		if ( !jQuery.support.opacity && name == "opacity" ) {
			if ( set ) {
				// IE has trouble with opacity if it does not have layout
				// Force it by setting the zoom level
				elem.zoom = 1;

				// Set the alpha filter to set the opacity
				elem.filter = (elem.filter || "").replace( /alpha\([^)]*\)/, "" ) +
					(parseInt( value ) + '' == "NaN" ? "" : "alpha(opacity=" + value * 100 + ")");
			}

			return elem.filter && elem.filter.indexOf("opacity=") >= 0 ?
				(parseFloat( elem.filter.match(/opacity=([^)]*)/)[1] ) / 100) + '':
				"";
		}

		name = name.replace(/-([a-z])/ig, function(all, letter){
			return letter.toUpperCase();
		});

		if ( set )
			elem[ name ] = value;

		return elem[ name ];
	}
});