一款利用asp文件上传组件把文件上传到服务器之前进行判断文件大小否超过指定大小了，本实例讲的是upload_5xsoft文件上传组件哦,file.filesize>1000000就可以限制文件为多少k。
dim upload,file,formname,formpath,icount,filename,fileext
set upload=new upload_5xsoft '建立上传对象
formpath="download/" '在目录后加(/)
if right(formpath,1)<>"/" then formpath=formpath&"/"
for each formname in upload.file '列出所有上传了的文件
set file=upload.file(formname) '生成一个文件对象
if file.filesize>1000000 then
message=1
else '如果 filesize <20000 说明有文件数据
fileext=lcase(right(file.filename,4))
if fileext<>".exe" and fileext<>".zip" and fileext<>".rar" and fileext<>".mxp" then
message=2
else
randomize
rannum=int(90000*rnd)+10000
filename=formpath& "lemongtree_" & year(now)&month(now)&day(now)&hour(now)&minute(now)&second(now)&rannum&fileext
file.saveas server.mappath(filename) '保存文件
if fileext=".zip" then
uploadtype = "zip"
elseif fileext=".rar" then
uploadtype = "rar"
elseif fileext=".mxp" then
uploadtype = "mxp"
elseif fileext=".exe" then
uploadtype = "exe"
end if
uploadchar = filename
size = clng(file.filesize)/1000
message=3
end if
end if
next
%>
<% if message=1 then%>
<html>
<head>
<title>大小超标</title>
<meta http-equiv="content-type" content="text/html; charset=gb2312">
<script language=网页特效>
function error_size()
{
alert("文件大小超过1000kb，请重新选择。");
window.location="upload.asp";
}
</script>
</head>
<body bgcolor="#f2f2f2" leftmargin="0" topmargin="0" onload="error_size()">
</body>
</html>
<% elseif message=2 then%>
<html>
<head>
<title>类型不匹配</title>
<meta http-equiv="content-type" content="text/html; charset=gb2312">
<script language=javascript>
function error_type()
{
alert("只能上传 zip / rar / exe /mxp 文件n请选择正确的文件类型！");
window.location="upload.asp";
}
</script>
</head>
<body bgcolor="#f2f2f2" leftmargin="0" topmargin="0" onload="error_type()">
</body>
</html>
<% elseif message=3 then%>
<html>
<head>
<title>上传成功</title>
<meta http-equiv="content-type" content="text/html; charset=gb2312">
<script language=javascript>
function image_success()
{
alert("文件上传成功！");
parent.form1.url1.value="<%=uploadchar %>"
parent.form1.size.value="<%=size%>k"
window.location="upload.asp";
}
</script>
</head>
<body bgcolor="#f2f2f2" leftmargin="0" topmargin="0" onload="image_success()">
</body>
</html>
<% end if %>
<%
set file=nothing
set upload=nothing ''删除此对象
%>