//数字验证
//<input type="text" onkeypress="javascript:return isNumber(event);"/>   
isNumber = function (e) {   
    if ($.browser.msie) {   
        if ( ((event.keyCode > 47) && (event.keyCode < 58)) ||   
              (event.keyCode == 8) ) {   
            return true;   
        } else {   
            return false;   
        }   
    } else {   
        if ( ((e.which > 47) && (e.which < 58)) ||   
              (e.which == 8) ) {   
            return true;   
        } else {   
            return false;   
        }   
    }   
}

// 统计字数
function textCounter(field, countfield, maxlimit) {
if (field.value.length > maxlimit)
	field.value = field.value.substring(0, maxlimit); 
else 
	document.getElementById(countfield).value = maxlimit - field.value.length;
}