js获得项目的根路径等的插件js代码，有效杜绝路径问题

(function(){
    //获取contextPath
    var contextPath=getContextPath();
    //获取basePath
    var basePath=getBathPath();
    //将获取到的contextPath和basePatj分别赋值给window对象的g_context和g_basePath属性
    window.g_contextPath=contextPath;
    window.g_basePath=basePath;
})();

/**
 * 获得项目根路径，等价于jsp页面中
 * <%
     String basePath=request.getScheme()+"://"+request.getServerName()+":"+request.getServerPort()+path+"/"
   %>
 */
function getBathPath(){
     var curWwwPath=window.document.location.href;
     var pathName=window.document.location.pathname;
     var pos = curWwwPath.indexOf(pathName);
     var localhostPath = curWwwPath.substring(0, pos);
     var projectName = pathName.substring(0, pathName.substr(1).indexOf('/') + 1);
     return (localhostPath + projectName);
}

/**
 * 获取web应用的contextPath，等价于jsp页面中
 * <%
     String path=request.getContextPath
   %>
 */
function getContextPath(){
    return window.document.location.pathname.substring(0,window.document.location.pathname.indexOf("\/",1));
}