DataBind Problem

[Chris Kennedy]

I have a drop down list, which binds to dataset based on an XML file like the one below.

<xmlform>
<formelement id="0">
<maxlength>234</maxlength>
<datatype>String</datatype>
<isnull>true</isnull>
<index>0</index>
</formelement>
</xmlform>

Sometime the XML will have nothing in it like so

<xmlform>
</xmlform>

The databind routine can't find any columns and hence throws an error. Is there a straight forward way to test for this an then not bind?

[JV]

You could preload it using XmlDocument and see if it has the nodes you are
expecting.

"Chris Kennedy" <ck**************@bleyonder.co.uk> I have a drop down list,
which binds to dataset based on an XML file like the one below.
The databind routine can't find any columns and hence throws an error. Is
there a straight forward way to test for this an then not bind?

[Chris Kennedy]

Could you give us a pointer in code as I am al ittle new to XML. Would a
node list in Xpath do the job?

"JV" <jo**********@goisc.com> wrote in message
news:u8*************@TK2MSFTNGP15.phx.gbl...

You could preload it using XmlDocument and see if it has the nodes you are
expecting.

"Chris Kennedy" <ck**************@bleyonder.co.uk> I have a drop down list, which binds to dataset based on an XML file like the one below.
The databind routine can't find any columns and hence throws an error. Is
there a straight forward way to test for this an then not bind?

[intrader]

On Fri, 01 Jul 2005 10:13:40 -0700, Chris Kennedy wrote:

Could you give us a pointer in code as I am al ittle new to XML. Would a
node list in Xpath do the job?

"JV" <jo**********@goisc.com> wrote in message
news:u8*************@TK2MSFTNGP15.phx.gbl...

You could preload it using XmlDocument and see if it has the nodes you are
expecting.

"Chris Kennedy" <ck**************@bleyonder.co.uk> I have a drop down

list,

which binds to dataset based on an XML file like the one below.
The databind routine can't find any columns and hence throws an error. Is
there a straight forward way to test for this an then not bind?

My approach - you say that you already have a DataSet from the XML (via
ReadXML() method). Look in the properties of the DataSet (for example
Tables gives you the tables collection); from this you can infer whether
dataset is empty and prevent the Bind.

[Chris Kennedy]

I tried doing a table count but could get it to work.I did this instead, it
works although I am sure you could something with less lines of code.

Function nodecount() As Integer
xmldoc = Session("xmldoc")
Dim intnodecount As Integer = 0
xmllist = xmldoc.GetElementsByTagName("formelement")
For Each xmlnode In xmllist
intnodecount = intnodecount + 1
Next
If intnodecount = 0 Then
lbltest.Text = "XML Config File is empty"
End If
Return intnodecount
End Function

"intrader" <in******@attglobal.net> wrote in message
news:pa****************************@attglobal.net. ..

On Fri, 01 Jul 2005 10:13:40 -0700, Chris Kennedy wrote:

Could you give us a pointer in code as I am al ittle new to XML. Would a
node list in Xpath do the job?

"JV" <jo**********@goisc.com> wrote in message
news:u8*************@TK2MSFTNGP15.phx.gbl...

You could preload it using XmlDocument and see if it has the nodes you are expecting.

"Chris Kennedy" <ck**************@bleyonder.co.uk> I have a drop down

list,

which binds to dataset based on an XML file like the one below.
The databind routine can't find any columns and hence throws an error. Is there a straight forward way to test for this an then not bind?

My approach - you say that you already have a DataSet from the XML (via
ReadXML() method). Look in the properties of the DataSet (for example
Tables gives you the tables collection); from this you can infer whether
dataset is empty and prevent the Bind.

[zdrakec]

Or, of course, you could use a Try..Except block, and trap the error
that gets thown when the list is empty...

Cheers,
zdrakec

[Juan T. Llibre]

Chris,

please fix your system date.

You're future posting.

Juan T. Llibre
ASP.NET MVP
http://asp.net.do/foros/
Foros de ASP.NET en Español
Ven, y hablemos de ASP.NET...
======================

"Chris Kennedy" <ck**************@bleyonder.co.uk> wrote in message
news:Ol**************@TK2MSFTNGP09.phx.gbl...

I tried doing a table count but could get it to work.I did this instead, it
works although I am sure you could something with less lines of code.

Function nodecount() As Integer
xmldoc = Session("xmldoc")
Dim intnodecount As Integer = 0
xmllist = xmldoc.GetElementsByTagName("formelement")
For Each xmlnode In xmllist
intnodecount = intnodecount + 1
Next
If intnodecount = 0 Then
lbltest.Text = "XML Config File is empty"
End If
Return intnodecount
End Function

"intrader" <in******@attglobal.net> wrote in message
news:pa****************************@attglobal.net. ..

On Fri, 01 Jul 2005 10:13:40 -0700, Chris Kennedy wrote:

> Could you give us a pointer in code as I am al ittle new to XML. Would a
> node list in Xpath do the job?
>
> "JV" <jo**********@goisc.com> wrote in message
> news:u8*************@TK2MSFTNGP15.phx.gbl...
>> You could preload it using XmlDocument and see if it has the nodes you are >> expecting.
>>
>> "Chris Kennedy" <ck**************@bleyonder.co.uk> I have a drop down
> list,
>> which binds to dataset based on an XML file like the one below.
>> The databind routine can't find any columns and hence throws an error. Is >> there a straight forward way to test for this an then not bind?
>>
>>

My approach - you say that you already have a DataSet from the XML (via
ReadXML() method). Look in the properties of the DataSet (for example
Tables gives you the tables collection); from this you can infer whether
dataset is empty and prevent the Bind.

[intrader]

On Sat, 02 Jul 2005 07:16:22 -0700, Chris Kennedy wrote:

I tried doing a table count but could get it to work.I did this instead, it
works although I am sure you could something with less lines of code.

Function nodecount() As Integer
xmldoc = Session("xmldoc")
Dim intnodecount As Integer = 0
xmllist = xmldoc.GetElementsByTagName("formelement")
For Each xmlnode In xmllist
intnodecount = intnodecount + 1
Next
If intnodecount = 0 Then
lbltest.Text = "XML Config File is empty"
End If
Return intnodecount
End Function

"intrader" <in******@attglobal.net> wrote in message
news:pa****************************@attglobal.net. ..

On Fri, 01 Jul 2005 10:13:40 -0700, Chris Kennedy wrote:

> Could you give us a pointer in code as I am al ittle new to XML. Would a
> node list in Xpath do the job?
>
> "JV" <jo**********@goisc.com> wrote in message
> news:u8*************@TK2MSFTNGP15.phx.gbl...
>> You could preload it using XmlDocument and see if it has the nodes you are >> expecting.
>>
>> "Chris Kennedy" <ck**************@bleyonder.co.uk> I have a drop down
> list,
>> which binds to dataset based on an XML file like the one below.
>> The databind routine can't find any columns and hence throws an error. Is >> there a straight forward way to test for this an then not bind?
>>
>>

My approach - you say that you already have a DataSet from the XML (via
ReadXML() method). Look in the properties of the DataSet (for example
Tables gives you the tables collection); from this you can infer whether
dataset is empty and prevent the Bind.

That works, but int the future just get Tables.length.