//限制areatext的输入字数
function clueLength(target, maxLength, element)
{
    target = $(target);
    if($.trim(target.val()).length > maxLength)
    {
        target.val($.trim(target.val()).substring(0, maxLength));
    }
    element.html(maxLength - $.trim(target.val()).length);
}


function SubmitKeyClick(button)
{   
    if (event.keyCode == 13)
    {
        event.keyCode=9;
        event.returnValue = false;
        document.all[button].click();
    }
}


(function($){
    //url编码
    $.urlEncode = function(value){
        return encodeURIComponent(value);
    };
    
    //url解码
    $.urlDecode = function(value){
        return decodeURIComponent(value);
    };
    
    //html编码
    $.htmlEncode = function(value){
        var encodeHTML = value.replace(/&/g, '&');
        encodeHTML = encodeHTML.replace(/>/g, '>');
        encodeHTML = encodeHTML.replace(/</g, '&lt;');
        encodeHTML = encodeHTML.replace(/\s/g, '&nbsp;');
        return encodeHTML;
    };
    
    //html解码
    $.htmlDecode = function(value){
        var encodeHTML = value.replace(/&amp;/g, '&');
        encodeHTML = encodeHTML.replace(/&gt;/g, '>');
        encodeHTML = encodeHTML.replace(/&lt;/g, '<');
        encodeHTML = encodeHTML.replace(/&nbsp;/g, ' ');
        return encodeHTML;
    };
    
    $.fn.center = function(){
        var top = ($(window).height() - this.height())/2;
        var left = ($(window).width() - this.width())/2;
        var scrollTop = $(document).scrollTop();
        var scrollLeft = $(document).scrollLeft();
        return this.css( { position : 'absolute', 'top' : top + scrollTop, left : left + scrollLeft } ).show();
    };
    
    $.fn.closeTo = function(target, options){
        var target = $(target);
        var targetOffset = target.offset();
        var css = {
            position : 'absolute',
            top : targetOffset.top + this.height,
            left : targetOffset.left
        };
        return this.css(css).show();
    };
})(jQuery)