Im just starting to experiment with network callbacks. Bellow is the relevent code in my aspx page:
<asp:ScriptManager ID="Scriptmanager1" runat="server">
<Services>
<asp:ServiceReference Path="~/SimpleService.asmx" />
</Services>
</asp:ScriptManager>
<script type="text/javascript">
function selProducts_onchange() {
ret = SimpleService.SayHello(document.getElementById("selProducts").value, WSComplete, WSTimeout, WSError);
return true;
}
function WSComplete(arg) {
document.getElementById("divDisplay").innerHTML = arg;
}
function WSTimeout(arg) {
document.getElementById("divDisplay").innerHTML = "***Web Service TIMEOUT*** " + arg;
}
function WSError(arg) {
...
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