Multiple DropDownLists

[Igor]

Hello

I have the following problem. I have three drop down lists on my page. They
are filled with data from a database. Initially only the first one is
enabled. The next one is enebled when user selects an item from the first
one -- it is then filled with data specific to the selection in the drop
down list above. The same with the third one. For each drop down list the
first item is always "--select an item--" (as described here:
http://weblogs.asp.net/scottgu/archi...9/436804.aspx). To enable
that I had to set the AppendDataBound Items property for all three drop down
lists to "true". Unfortunatelly, when a user selects an item from the first
drop down list, the second one gets filled with item "--select an item--"
and data from the database. But if the user changes their mind and selects
different item from the first list (or list above in the structure) the next
drop down list gets filled with new data, but, because of the
AppendDataBound Items property set to "true", previous data remains in the
list. Thus, I must clear list(s) when user makes change to the selection
above in the structure. How can I do this?

Kind regards

IgorM

[David Wier]

ddl.items.clear

David Wier
http://aspnet101.com
http://iWritePro.com - One click PDF, convert .doc/.rtf/.txt to HTML with no
bloated markup
"Igor" <ig***@live.com wrote in message
news:22******** *************** ***********@mic rosoft.com...

Hello

I have the following problem. I have three drop down lists on my page.
They are filled with data from a database. Initially only the first one is
enabled. The next one is enebled when user selects an item from the first
one -- it is then filled with data specific to the selection in the drop
down list above. The same with the third one. For each drop down list the
first item is always "--select an item--" (as described here:
http://weblogs.asp.net/scottgu/archi...9/436804.aspx). To enable
that I had to set the AppendDataBound Items property for all three drop
down lists to "true". Unfortunatelly, when a user selects an item from the
first drop down list, the second one gets filled with item "--select an
item--" and data from the database. But if the user changes their mind and
selects different item from the first list (or list above in the
structure) the next drop down list gets filled with new data, but, because
of the AppendDataBound Items property set to "true", previous data remains
in the list. Thus, I must clear list(s) when user makes change to the
selection above in the structure. How can I do this?

Kind regards

IgorM

[Igor]

Hi

I didn't make myself clear enough. Where should I put it in the code ? I
tried putting it in SelectedIndexCh anged events of particular drop down
lists as well as PageLoad event but than I had a problem with a statement
that selects first item (the one with "--select item --" text ) in the drop
down lists below in the hierarchy because it fired exceptions. By
ddl.items.clear the first item, the "--select item--" is also cleares, and
it is not added again in postbacks.

Kind regars
IgorM

"David Wier" <[e-mail] te in message
news:%2******** ********@TK2MSF TNGP04.phx.gbl. ..

ddl.items.clear

David Wier
http://aspnet101.com
http://iWritePro.com - One click PDF, convert .doc/.rtf/.txt to HTML with
no bloated markup
"Igor" <ig***@live.com wrote in message
news:22******** *************** ***********@mic rosoft.com...

>Hello

I have the following problem. I have three drop down lists on my page.
They are filled with data from a database. Initially only the first one
is enabled. The next one is enebled when user selects an item from the
first one -- it is then filled with data specific to the selection in the
drop down list above. The same with the third one. For each drop down
list the first item is always "--select an item--" (as described here:
http://weblogs.asp.net/scottgu/archi...9/436804.aspx). To enable
that I had to set the AppendDataBound Items property for all three drop
down lists to "true". Unfortunatelly, when a user selects an item from
the first drop down list, the second one gets filled with item "--select
an item--" and data from the database. But if the user changes their mind
and selects different item from the first list (or list above in the
structure) the next drop down list gets filled with new data, but,
because of the AppendDataBound Items property set to "true", previous data
remains in the list. Thus, I must clear list(s) when user makes change to
the selection above in the structure. How can I do this?

Kind regards

IgorM

[David Wier]

You should put it anywhere you need it, in any event handler, just before
you're populating the ddl.
Anothere thing - if you're populating any ddls in the Page_Load event, be
sure to surround that population with an if/then/Postback block

David Wier
http://aspnet101.com
http://iWritePro.com - One click PDF, convert .doc/.rtf/.txt to HTML with no
bloated markup
"Igor" <ig***@live.com wrote in message
news:0D******** *************** ***********@mic rosoft.com...

Hi

I didn't make myself clear enough. Where should I put it in the code ? I
tried putting it in SelectedIndexCh anged events of particular drop down
lists as well as PageLoad event but than I had a problem with a statement
that selects first item (the one with "--select item --" text ) in the
drop down lists below in the hierarchy because it fired exceptions. By
ddl.items.clear the first item, the "--select item--" is also cleares, and
it is not added again in postbacks.

Kind regars
IgorM

"David Wier" <[e-mail] te in message
news:%2******** ********@TK2MSF TNGP04.phx.gbl. ..

>ddl.items.clea r

David Wier
http://aspnet101.com
http://iWritePro.com - One click PDF, convert .doc/.rtf/.txt to HTML with
no bloated markup
"Igor" <ig***@live.com wrote in message
news:22******* *************** ************@mi crosoft.com...

>>Hello

I have the following problem. I have three drop down lists on my page.
They are filled with data from a database. Initially only the first one
is enabled. The next one is enebled when user selects an item from the
first one -- it is then filled with data specific to the selection in
the drop down list above. The same with the third one. For each drop
down list the first item is always "--select an item--" (as described
here: http://weblogs.asp.net/scottgu/archi...9/436804.aspx). To
enable that I had to set the AppendDataBound Items property for all three
drop down lists to "true". Unfortunatelly, when a user selects an item
from the first drop down list, the second one gets filled with item
"--select an item--" and data from the database. But if the user changes
their mind and selects different item from the first list (or list above
in the structure) the next drop down list gets filled with new data,
but, because of the AppendDataBound Items property set to "true",
previous data remains in the list. Thus, I must clear list(s) when user
makes change to the selection above in the structure. How can I do this?

Kind regards

IgorM

[Igor]

Still don't know how to get the first item to be "--select value--" in code
behind if I cannot use the <asp:ListItem Text="-- select value --"
Value="">.
"David Wier" <[e-mail] te in message
news:O8******** ******@TK2MSFTN GP02.phx.gbl...

You should put it anywhere you need it, in any event handler, just before
you're populating the ddl.
Anothere thing - if you're populating any ddls in the Page_Load event, be
sure to surround that population with an if/then/Postback block

David Wier
http://aspnet101.com
http://iWritePro.com - One click PDF, convert .doc/.rtf/.txt to HTML with
no bloated markup
"Igor" <ig***@live.com wrote in message
news:0D******** *************** ***********@mic rosoft.com...

>Hi

I didn't make myself clear enough. Where should I put it in the code ? I
tried putting it in SelectedIndexCh anged events of particular drop down
lists as well as PageLoad event but than I had a problem with a statement
that selects first item (the one with "--select item --" text ) in the
drop down lists below in the hierarchy because it fired exceptions. By
ddl.items.clea r the first item, the "--select item--" is also cleares,
and it is not added again in postbacks.

Kind regars
IgorM

"David Wier" <[e-mail] te in message
news:%2******* *********@TK2MS FTNGP04.phx.gbl ...

>>ddl.items.cle ar

David Wier
http://aspnet101.com
http://iWritePro.com - One click PDF, convert .doc/.rtf/.txt to HTML
with no bloated markup
"Igor" <ig***@live.com wrote in message
news:22****** *************** *************@m icrosoft.com...
Hello

I have the following problem. I have three drop down lists on my page.
They are filled with data from a database. Initially only the first one
is enabled. The next one is enebled when user selects an item from the
first one -- it is then filled with data specific to the selection in
the drop down list above. The same with the third one. For each drop
down list the first item is always "--select an item--" (as described
here: http://weblogs.asp.net/scottgu/archi...9/436804.aspx).
To enable that I had to set the AppendDataBound Items property for all
three drop down lists to "true". Unfortunatelly, when a user selects an
item from the first drop down list, the second one gets filled with
item "--select an item--" and data from the database. But if the user
changes their mind and selects different item from the first list (or
list above in the structure) the next drop down list gets filled with
new data, but, because of the AppendDataBound Items property set to
"true", previous data remains in the list. Thus, I must clear list(s)
when user makes change to the selection above in the structure. How can
I do this?

Kind regards

IgorM

[Mark Elliott]

Would something like the following work?

DropDownList ddl = new DropDownList();
ListItem li = new ListItem("--select item--");
ddl.Items.Inser t(li);

On Thu, 12 Jun 2008 13:57:18 -0300, Igor <ig***@live.com wrote:

Still don't know how to get the first item to be "--select value--" in
code behind if I cannot use the <asp:ListItem Text="-- select value --"
Value="">.
"David Wier" <[e-mail] te in message
news:O8******** ******@TK2MSFTN GP02.phx.gbl...

>You should put it anywhere you need it, in any event handler, just
before you're populating the ddl.
Anothere thing - if you're populating any ddls in the Page_Load event,
be sure to surround that population with an if/then/Postback block

David Wier
http://aspnet101.com
http://iWritePro.com - One click PDF, convert .doc/.rtf/.txt to HTML
with no bloated markup
"Igor" <ig***@live.com wrote in message
news:0D******* *************** ************@mi crosoft.com...

>>Hi

I didn't make myself clear enough. Where should I put it in the code ?
I tried putting it in SelectedIndexCh anged events of particular drop
down lists as well as PageLoad event but than I had a problem with a
statement that selects first item (the one with "--select item --"
text ) in the drop down lists below in the hierarchy because it fired
exceptions. By ddl.items.clear the first item, the "--select item--"
is also cleares, and it is not added again in postbacks.

Kind regars
IgorM

"David Wier" <[e-mail] te in message
news:%2****** **********@TK2M SFTNGP04.phx.gb l...
ddl.items.cl ear

David Wier
http://aspnet101.com
http://iWritePro.com - One click PDF, convert .doc/.rtf/.txt to HTML
with no bloated markup
"Igor" <ig***@live.com wrote in message
news:22***** *************** **************@ microsoft.com.. .
Hello
>
I have the following problem. I have three drop down lists on my
page. They are filled with data from a database. Initially only the
first one is enabled. The next one is enebled when user selects an
item from the first one -- it is then filled with data specific to
the selection in the drop down list above. The same with the third
one. For each drop down list the first item is always "--select an
item--" (as described here:
http://weblogs.asp.net/scottgu/archi...9/436804.aspx). To
enable that I had to set the AppendDataBound Items property for all
three drop down lists to "true". Unfortunatelly, when a user selects
an item from the first drop down list, the second one gets filled
with item "--select an item--" and data from the database. But if
the user changes their mind and selects different item from the
first list (or list above in the structure) the next drop down list
gets filled with new data, but, because of the AppendDataBound Items
property set to "true", previous data remains in the list. Thus, I
must clear list(s) when user makes change to the selection above in
the structure. How can I do this?
>
Kind regards
>
IgorM

--
Using Opera's revolutionary e-mail client: http://www.opera.com/mail/

[Steve C. Orr [MCSD, MVP, CSM, ASP Insider]]

Perhaps you can use this free control to make your life easier:
http://www.asp.net/AJAX/AjaxControlT...gDropDown.aspx

--
I hope this helps,
Steve C. Orr,
MCSD, MVP, CSM, ASPInsider
http://SteveOrr.net
http://iPhonePlaza.net
"Igor" <ig***@live.com wrote in message
news:22******** *************** ***********@mic rosoft.com...

Hello

I have the following problem. I have three drop down lists on my page.
They are filled with data from a database. Initially only the first one is
enabled. The next one is enebled when user selects an item from the first
one -- it is then filled with data specific to the selection in the drop
down list above. The same with the third one. For each drop down list the
first item is always "--select an item--" (as described here:
http://weblogs.asp.net/scottgu/archi...9/436804.aspx). To enable
that I had to set the AppendDataBound Items property for all three drop
down lists to "true". Unfortunatelly, when a user selects an item from the
first drop down list, the second one gets filled with item "--select an
item--" and data from the database. But if the user changes their mind and
selects different item from the first list (or list above in the
structure) the next drop down list gets filled with new data, but, because
of the AppendDataBound Items property set to "true", previous data remains
in the list. Thus, I must clear list(s) when user makes change to the
selection above in the structure. How can I do this?

Kind regards

IgorM