JQuery.isExtend is a project mainly written in JavaScript, it's free.
== SUMMARY
jQuery.isExtend is a jQuery plugin to determine the type.
== Example
Test page see http://benz303.github.com/jQuery.isExtend/
jQuery.isElement jQuery.isArray jQuery.isObject jQuery.isArguments jQuery.isFunction jQuery.isString jQuery.isNumber jQuery.isNaN jQuery.isBoolean jQuery.isDate jQuery.isRegExp jQuery.isNull jQuery.isUndefined jQuery.isjQuery
jQuery.isType(obj) jQuery.isType(obj, types)
jQuery.isEmpty jQuery.isBlank = jQuery.isEmpty;