I have the following code (this is a snippet):
InitDBConn();
OpenDBConnectio n();
OleDbCommand cmdRidge = new OleDbCommand("S ELECT * FROM
TRDRidgeTypes", oleDbConn);
OleDbDataReader oleRidges= cmdRidge.Execut eReader();
if (!this.IsPostBa ck)
{
ddlRidge.DataSo urce = oleRidges;
ddlRidge.DataMe mber = "TRDRidgeTypes" ;
ddlRidge.DataTe xtField = "RidgeType" ;
ddlRidge.DataVa lueField = "RidgeTypeI D";
ddlRidge.DataBi nd();
}
----
This code successfully fills a DropDownList box. However, when the
user selects one of the items and the page is posted to the server
,the SelectedItem property of the List is null and the SelectedIndex i
(-1). I am tearing my hair out because I have found people on the
newsgroup with a similar
problem, but it was due to their not setting data source in the
"this.PostB ack =False" condition. I have done that, and it still does
not help me.
I do have ViewState for the control set to True. I tried hardcoding
the ListItems in the HTML and the control values were read correctly.
I am sure I am missing the obvious here..but please help!!
Thanks,
Stacey 2 4749
You don't want to bind the data on post-back.
You are wiping out the results when you bind the data!
only bind when postback is TRUE, or when you know the
content will/should be changing. Otherwise, the viewstate
will handle everything else for you automatically.
email if you need more... -----Original Message----- I have the following code (this is a snippet):
InitDBConn() ; OpenDBConnecti on();
OleDbCommand cmdRidge = new OleDbCommand("S ELECT * FROM TRDRidgeTypes" , oleDbConn);
OleDbDataReade r oleRidges= cmdRidge.Execut eReader();
if (!this.IsPostBa ck) { ddlRidge.DataS ource = oleRidges; ddlRidge.DataM ember = "TRDRidgeTypes" ; ddlRidge.DataT extField = "RidgeType" ; ddlRidge.DataV alueField = "RidgeTypeI D"; ddlRidge.DataB ind(); }
---- This code successfully fills a DropDownList box. However,
when theuser selects one of the items and the page is posted to
the server,the SelectedItem property of the List is null and the
SelectedIndex i(-1). I am tearing my hair out because I have found
people on thenewsgroup with a similar problem, but it was due to their not setting data source
in the"this.PostBa ck =False" condition. I have done that, and
it still doesnot help me.
I do have ViewState for the control set to True. I tried
hardcodingthe ListItems in the HTML and the control values were
read correctly. I am sure I am missing the obvious here..but please help!!
Thanks, Stacey .
Stacey is not binding on the postback--at least not in the code below.
Notice the ! (not) in the IF statement. The code shown says to do the
binding if it's not a postback.
We need to see more of the code. What else happens if it IS a postback?
Do you manually re-populate the dropdownlist if it is a postback. If
that's the case, then that's the problem.
-bliz
--
Jim Blizzard
Sr .NET Developer Evangelist
Microsoft
Your Potential. Our Passion.
This posting is provided "AS IS" with no warranties, and confers no rights.
Please reply to newsgroups only, so that others may benefit. Thanks.
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You don't want to bind the data on post-back. You are wiping out the results when you bind the data!
only bind when postback is TRUE, or when you know the content will/should be changing. Otherwise, the viewstate will handle everything else for you automatically.
email if you need more...
-----Original Message----- I have the following code (this is a snippet):
InitDBConn( ); OpenDBConnect ion();
OleDbComman d cmdRidge = new OleDbCommand("S ELECT * FROM TRDRidgeTypes ", oleDbConn);
OleDbDataRead er oleRidges= cmdRidge.Execut eReader();
if (!this.IsPostBa ck) { ddlRidge.Data Source = oleRidges; ddlRidge.Data Member = "TRDRidgeTypes" ; ddlRidge.Data TextField = "RidgeType" ; ddlRidge.Data ValueField = "RidgeTypeI D"; ddlRidge.Data Bind(); }
---- This code successfully fills a DropDownList box. However, when theuser selects one of the items and the page is posted to the server,the SelectedItem property of the List is null and the SelectedInde x i(-1). I am tearing my hair out because I have found people on thenewsgroup with a similar problem, but it was due to their not setting data source in the"this.PostBac k =False" condition. I have done that, and it still doesnot help me.
I do have ViewState for the control set to True. I tried hardcodingthe ListItems in the HTML and the control values were read correctly. I am sure I am missing the obvious here..but please help!!
Thanks, Stacey .
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