// HTTP通信用、共通関数
function AjaxRequest(event) {
    var value = null;
    try{
        value = new XMLHttpRequest();
    }catch(e){
        try{
            value = new ActiveXObject("Msxml2.XMLHTTP");
        }catch(e){
            try{
                value = new ActiveXObject("Microsoft.XMLHTTP");
            }catch(e){
                return null;
            }
        }
    }
    if (value) value.onreadystatechange = event;
    return value;
}