Js常用方法

String.prototype.trim = function()
{
return this.replace(eval(arguments[0]?  '/(^' + arguments[0] + '*)|(' + arguments[0] + '*$)/g': '/(^\s*)|(\s*$)/g'), "");
}

jQuery.fn.onlyNum = function(){
$(this).live('keydown', function(event){
var key = event.which;
if(key < 48 || key > 57)
{
if((key < 96 || key > 105) && key != 8)
{
return false;
}
}
});
};

jQuery.fn.getUrlParam = function(paras)
{
var url = location.href;
var paraString = url.substring(url.indexOf("?")+1,url.length).split("&");
var paraObj = {}
for (i=0; j=paraString[i]; i++){
paraObj[j.substring(0,j.indexOf("=")).toLowerCase()] = j.substring(j.indexOf("=")+1,j.length);
}
var returnValue = paraObj[paras.toLowerCase()];
if(typeof(returnValue)=="undefined"){
return "";
}else{
return returnValue;
}
}

function setCookie(name, value, time)
{
if(name != '')
{
if(!time)
time = 60*60*24;
if(time > 0)
{
var $date = new Date();
$date.setTime($date.getTime() + parseInt(time));
document.cookie = name + '=' + escape(value) + ';expires=' + $date.toGMTString();
}
}
}
function getCookie(name)//取cookies函数
{

var arr = document.cookie.match(new RegExp("(^| )"+name+"=([^;]*)(;|$)"));
if(arr != null) return unescape(arr[2]); return null;
}

function delCookie(name)//删除cookie
{
var exp = new Date();
exp.setTime(exp.getTime() - 1);
var cval=getCookie(name);
if(cval!=null) document.cookie= name + "="+cval+";expires="+exp.toGMTString();
}

jQuery.fn.defCont = function(obj){
var settings = {
oldcolor : '',
newcolor : '',
title_tag : 'show_default'
};
if(obj)
{
$.extend(settings,obj);
}
$(this).live('focus', function(){
$(this).attr(settings.title_tag, $(this).val()).val('');
if(settings.newcolor != '')
{
$(this).css({'color':settings.newcolor});
}
});
$(this).live('blur', function(){
var thisValue = $(this).val();
if(thisValue.trim() == '')
{
$(this).val($(this).attr(settings.title_tag));
if(settings.oldcolor != '')
{
$(this).css({'color':settings.oldcolor});
}
}
});
};