sub chk()
if request("a")="" or request("b")="" then
response.write("<script>alert('两项中必填一项。');</script>")
exit sub
end if
end sub
if request("a")="" or request("b")="" then
response.write("<script>alert('两项中必填一项。');</script>")
exit sub
end if
end sub
<input name=a type=text>
<input name=b type=text>
<input type="button" onclick="sub()">
</form>function sub(){
if(form1.a.value == "" && form1.b.value == ""){
alert("两项中必填一项");
}
else{
form1.submit();
}
}
alert("两项中必填一项");