function gbcount(message,total,used,remain) { var max; max = total.value; if (message.value.length > max) { message.value = message.value.substring(0,max); used.value = max; remain.value = 0; alert("留言不能超过 3000 个字!"); } else { used.value = message.value.length; remain.value = max - used.value; } } document.write("