常用js代码

// JavaScript Document

//获取cookie
function getCookie( name ) {
var start = document.cookie.indexOf( name + "=" );
var len = start + name.length + 1;
if ( ( !start ) && ( name != document.cookie.substring( 0, name.length ) ) ) {
return null;
}
if ( start == -1 ) return null;
var end = document.cookie.indexOf( ';', len );
if ( end == -1 ) end = document.cookie.length;
return unescape( document.cookie.substring( len, end ) );
}
//设置cookie
function setCookie( name, value, expires, path, domain, secure ) {
var today = new Date();
today.setTime( today.getTime() );
if ( expires ) {
expires = expires * 1000 * 60 * 60 * 24;
}
var expires_date = new Date( today.getTime() + (expires) );
document.cookie = name+'='+escape( value ) +
( ( expires ) ? ';expires='+expires_date.toGMTString() : '' ) + //expires.toGMTString()
( ( path ) ? ';path=' + path : '' ) +
( ( domain ) ? ';domain=' + domain : '' ) +
( ( secure ) ? ';secure' : '' );
}
//删除cookie
function deleteCookie( name, path, domain ) {
if ( getCookie( name ) ) document.cookie = name + '=' +
( ( path ) ? ';path=' + path : '') +
( ( domain ) ? ';domain=' + domain : '' ) +
';expires=Thu, 01-Jan-1970 00:00:01 GMT';
}

//设置样式
function setStyle(el,prop,value){
if(prop == "opacity" && !+"\v1"){
//IE7 bug:filter 滤镜要求 hasLayout=true 方可执行（否则没有效果）
if (!el.currentStyle || !el.currentStyle.hasLayout) el.style.zoom = 1;
prop = "filter";
if(!!window.XDomainRequest){
value ="progid:DXImageTransform.Microsoft.Alpha(style=0,opacity="+value*100+")";
}else{
value ="alpha(opacity="+value*100+")"
}
}
el.style.cssText += ';' + (prop+":"+value);
}
//获取样式
function getStyle(el, style){
if(!+"\v1"){
style = style.replace(/\-(\w)/g, function(all, letter){
return letter.toUpperCase();
});
return el.currentStyle[style];
}else{
return document.defaultView.getComputedStyle(el, null).getPropertyValue(style)
}
}
//获取id
function $() {
var elements = [];
for (var i = 0; i < arguments.length; i++) {
var element = arguments[i];
if (typeof element == 'string')
element = document.getElementById(element);
if (arguments.length == 1)
return element;
elements.push(element);
}
return elements;
}
//添加事件
function addEvent(elm, evType, fn, useCapture) {
if (elm.addEventListener) {
elm.addEventListener(evType, fn, useCapture);//DOM2.0
return true;
}
else if (elm.attachEvent) {
var r = elm.attachEvent('on' + evType, fn);//IE5+
return r;
}
else {
elm['on' + evType] = fn;//DOM 0
}
}
//移除事件
function removeEvent(elm, evType, fn, useCapture) {
if (elm.removeEventListener) {
elm.removeEventListener(evType, fn, useCapture);//DOM2.0
return true;
}
else if (elm.detachEvent) {
var r = elm.detachEvent('on' + evType, fn);//IE5+
return r;
}
else {
elm['on' + evType] = fn;//DOM 0
}
}