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Creating Cascading Combo boxes in ASP

I'd like to create "cascading" combo boxes on a webpage with ASP using VBScript. By cascading I mean the second combo box depends on the value selected in the first, and the third combo box depends on the value selected in the second. I connect to a Access 2002 database with ADO to populate the combo boxes. The thing is, I'd like to do it without reloading the page each time a value is selected. What's the easy way to do this?
Any help would be appreciated.
Thanks,

mv

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Silversoft

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Michael Vasilevsky

ASKER

That looks nice. I don't know any javascript, so how would you populate the array with database values? Also why:

lists['USA'][0] = new Array(
'New York',
'Los Angeles'
);
lists['USA'][1] = new Array(
'New York',
'Los Angeles'
);
?
Seems redundant to have to state the values twice.
Finally, is there no vbscript solution?
Thanks,

mv

mrwebdev

Nice... Good Advice SilverSoft!

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markomni

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Silversoft

Sorry forgot to comment, one array is the actula display text and the other is the value of the combo box.
Regarding VBscript, I wouldnt recommend VBscript as a client language as it only compatible with MS IE and none of the others, Javascript is more standard and more compatible.

*****************************************************************

// First set of text and values
lists['Australia'] = new Array();
//TEXT ARRAY
lists['Australia'][0] = new Array(
'Sydney',
'Brisbane'
);
//VALUE ARRAY
lists['Australia'][1] = new Array(
'Sydney',
'Brisbane'
);

// Second set of text and values
lists['USA'] = new Array();
//TEXT ARRAY
lists['USA'][0] = new Array(
'New York',
'Los Angeles'
);
//VALUE ARRAY
lists['USA'][1] = new Array(
'New York',
'Los Angeles'
);

*****************************************************************

If you would like to insert values from DB, you can do something like this:

lists['Australia'][0] = new Array(
<%
for counter = 1 to rs.recordcount
response.write rs("field1")
loop
%>

just some ideas....
);

Michael Vasilevsky

ASKER

Looks good. Just one more question then I'll close this out: Is it true that I can only query the db with server-side scripting and therefore need to re-load the page each time the combo box is changed? I'd like to avoid that if possible, but it doesn't seem do-able.
Thanks for all the help!

mv

markomni

I just found some JavaScript code that may be useful to you:

http://members.aol.com/grassblad/html/selCascade2.html

Silversoft

Hi mvasilevsky

You don't necessarily need to reload the page each time a new option is selected in the primary combobox. All you have to do is to preload all the options for the combobox all at once and store them in a javascript array like demostrated above. It may take a bit longer to preload all the options if you have thousands of options to load, but i think it will nevertheless avoid the page reload that is required when a new option is selected.

regards- :)