Code:
<HTML>
<HEAD>
<script language="VBScript">
Sub Total( aButton )
Dim sum, frm
Set frm = aButton.form
sum = CDBL( frm.nom0.value ) + CDBL( frm.nom1.value ) + CDBL( frm.nom2.value )
frm.sum.value = FormatNumber( sum )
End Sub
</script>
</HEAD>
<BODY>
<FORM>
<TABLE BORDER="0">
<TR>
<TD>Enter a Number</TD>
<TD><INPUT NAME="nom0" SIZE="10"></TD>
</TR>
<TR>
<TD>Enter a Number</TD>
<TD><INPUT NAME="nom1" SIZE="10"></TD>
</TR>
<TR>
<TD>Enter a Number</TD>
<TD><INPUT NAME="nom2" SIZE="10"></TD>
</TR>
<TR>
<TD align=right>Total:</TD>
<TD><INPUT NAME="sum" SIZE="10" readonly></TD>
</TR>
<TR>
<TD></TD>
<TD><INPUT Type=Button Value="Get total" onClick="Call Total(me)"></TD>
</TR>
</TABLE>
</FORM>
</BODY>
</HTML>