// JScript 文件
 var domType = ''; 
 var objects=new Array(); 
if (document.all)
    { 
        domType = "ie4"; 
    }
    else if (document.getElementById) 
    { 
        domType = "std"; 
    } 
    else if (document.layers) 
    { 
        domType = "ns4"; 
    } 
    
function fetch_object(idname, forcefetch) 
    { 
        if (forcefetch || typeof(objects[idname]) == "undefined") 
        { 
            switch (domType) 
            { 
                case "std": 
                { 
                    objects[idname] = document.getElementById(idname); 
                } 
                    break; 

                case "ie4": 
                { 
                    objects[idname] = document.all[idname]; 
                } 
                    break; 

                case "ns4": 
                { 
                    objects[idname] = document.layers[idname]; 
                } 
                    break; 
            } 
        } 
        return objects[idname]; 
    }