function mainChange(strId)
{
    var objGoods = document.getElementById('goods');
    var objLogistic = document.getElementById('logistic');
    var objTransline = document.getElementById('transline');
    var objTrade = document.getElementById('trade');
    var objCompany = document.getElementById('company');
    var objNews = document.getElementById('news');
    switch(strId)
    {
        case "goods":
        {
             objGoods.style.display = '';
             objLogistic.style.display = 'none';
             objTransline.style.display = 'none';
             objTrade.style.display = 'none'; 
             objCompany.style.display = 'none';
             objNews.style.display = 'none';
             break;
        }
        case "logistic":
        {
             objGoods.style.display = 'none';
             objLogistic.style.display = '';
             objTransline.style.display = 'none';
             objTrade.style.display = 'none'; 
             objCompany.style.display = 'none';
             objNews.style.display = 'none';
             break;
        }
        case "transline":
        {
             objGoods.style.display = 'none';
             objLogistic.style.display = 'none';
             objTransline.style.display = '';
             objTrade.style.display = 'none'; 
             objCompany.style.display = 'none';
             objNews.style.display = 'none';
             break;
        }
        case "trade":
        {
             objGoods.style.display = 'none';
             objLogistic.style.display = 'none';
             objTransline.style.display = 'none';
             objTrade.style.display = ''; 
             objCompany.style.display = 'none';
             objNews.style.display = 'none';
             break;
        }
        case "company":
        {
             objGoods.style.display = 'none';
             objLogistic.style.display = 'none';
             objTransline.style.display = 'none';
             objTrade.style.display = 'none'; 
             objCompany.style.display = '';
             objNews.style.display = 'none';
             break;
        }
        case "news":
        {
             objGoods.style.display = 'none';
             objLogistic.style.display = 'none';
             objTransline.style.display = 'none';
             objTrade.style.display = 'none'; 
             objCompany.style.display = 'none';
             objNews.style.display = '';
             break; 
        }
         default:
             break;
    }
}