change value of textbox in datagrid

[simon]

hello,
new to vb.net, have a few questions about DataGrid. I have a dataGrid
that is working pulling a dataset back from a stored proc and binding
to the datagrid for display
the datagrid's first column is a textbox(Templat eColumn), the other 3
columns are just display(BoundCo lumn).

(1) if the value of the textbox is 0, then i'd like to change it null,
so the box is empty

i tried this...

For Each PickGridItem In draftPickGrid.I tems
If Convert.ToInt16 (CType(PickGrid Item.FindContro l("tPriority" ),
TextBox).Text) = 0 Then
CType(PickGridI tem.FindControl ("tPriority" ), TextBox).Text = ""
End If
Next

this or variation of it didn't work. help?
(2) after the user click the button, I have a function that kicks off
that i wanted to loop the dataset, get a few values (one if which is
the textbox), and then call a proc to update the data

i tried this....

For Each DemoGridItem In draftPickGrid.I tems

EventId = Convert.ToInt16 (DemoGridItem.C ells(2).Text)
Priority =
Convert.ToInt16 (CType(DemoGrid Item.FindContro l("tPriority" ),
TextBox).Text)
DraftPicks.Upda teDraftPick(gro upID, EventId, userID, Priority)
Next

I was getting a "Object reference not set to an instance of an object"
on Priority

also tried these lines to capture the value of the textbox

Dim tb As TextBox
tb = DemoGridItem.Fi ndControl("tPri ority")
Priority = Convert.ToInt16 (tb.Text)

that didn't work either, same error

i'm using visual studio 2003 and put a break point on the function
that is called to loop and call the update proc, i have these
declaration lines at the top of the function

Dim EventId As Integer
Dim Priority As Integer
Dim DemoGridItem As DataGridItem
Dim DraftPicks As New DraftPicksDB
it will skip over the first three Dim lines, Dim the 4th and then move
to the for loop. in the loop when i hit the priority (textbox)
processing line the error is then thrown.

any help/advice would be appreciated - sample code is always welcome
:)
thanks in advance!

[AMDRIT]

I would think it is better to ask the data container for zero length strings
and set the value to null from there.

my perferred way (barring stored procedures.)

for each dr as datarow in ctype(dbgdata.d atasource, datatable)
if not dr.isnull("Fiel dToCheck") andalso ctype(dr("Field ToCheck"),
string).length= 0 then
dr.beginedit
dr("FieldToChec k") = system.dbnull.v alue
dr.endedit
end if
next

you can become even more specific by using

for each dr as datarow in ctype(dbgdata.d atasource,
datatable).getc hanges(Added or Modified)

Another thing you can try is to monitor when the selected row of a datagrid
changes.

private m_CurrentRowInd ex as integer
privatee m_CurrencyManag er as CurrencyManager

private sub form_load
m_CurrencyManag er =
ctype(me.bindin gcontext(dbgdat a.datasource),c urrencymanager)

'Optionally issue
m_CurrencyManag er.Refresh
end sub

private sub m_CurrencyManag er_PositionChan ged(Sender, e) handles
m_CurrencyManag er.PositionChan ged
'Todo: add logic if you allow column sorting....

if me.dbgDatga.Cur rentrowIndex <> m_currentrowind ex then

dim dr as datarow= ctype(dbgdata.d atasource,
datatable).rows (m_currentrowin dex)

if not dr.isnull("Fiel dToCheck") andalso ctype(dr("Field ToCheck"),
string).length= 0 then
dr.beginedit
dr("FieldToChec k") = system.dbnull.v alue
dr.endedit
end if

dbgDatga.Curren trowIndex = m_currentrowind ex

'Optionally issue
m_CurrencyManag er.Refresh

end if

end sub

"simon" <[e-mail]> wrote in message
news:hk******** *************** *********@4ax.c om...

hello,
new to vb.net, have a few questions about DataGrid. I have a dataGrid
that is working pulling a dataset back from a stored proc and binding
to the datagrid for display
the datagrid's first column is a textbox(Templat eColumn), the other 3
columns are just display(BoundCo lumn).

(1) if the value of the textbox is 0, then i'd like to change it null,
so the box is empty

i tried this...

For Each PickGridItem In draftPickGrid.I tems
If Convert.ToInt16 (CType(PickGrid Item.FindContro l("tPriority" ),
TextBox).Text) = 0 Then
CType(PickGridI tem.FindControl ("tPriority" ), TextBox).Text = ""
End If
Next

this or variation of it didn't work. help?
(2) after the user click the button, I have a function that kicks off
that i wanted to loop the dataset, get a few values (one if which is
the textbox), and then call a proc to update the data

i tried this....

For Each DemoGridItem In draftPickGrid.I tems

EventId = Convert.ToInt16 (DemoGridItem.C ells(2).Text)
Priority =
Convert.ToInt16 (CType(DemoGrid Item.FindContro l("tPriority" ),
TextBox).Text)
DraftPicks.Upda teDraftPick(gro upID, EventId, userID, Priority)
Next

I was getting a "Object reference not set to an instance of an object"
on Priority

also tried these lines to capture the value of the textbox

Dim tb As TextBox
tb = DemoGridItem.Fi ndControl("tPri ority")
Priority = Convert.ToInt16 (tb.Text)

that didn't work either, same error

i'm using visual studio 2003 and put a break point on the function
that is called to loop and call the update proc, i have these
declaration lines at the top of the function

Dim EventId As Integer
Dim Priority As Integer
Dim DemoGridItem As DataGridItem
Dim DraftPicks As New DraftPicksDB
it will skip over the first three Dim lines, Dim the 4th and then move
to the for loop. in the loop when i hit the priority (textbox)
processing line the error is then thrown.

any help/advice would be appreciated - sample code is always welcome
:)
thanks in advance!

[simon]

thank you for the reply.
i have figured out what i was looking to do (may not be the best way
so please feel free to comment)

for setting the value of a textbox to null if it contain a "0" after
loading/binding it (for display purposes not storage in the db),
i did....

Private Sub SetPriorityZero ToNull()

Dim DemoGridItem As DataGridItem

For Each DemoGridItem In draftPickGrid.I tems
If CType(DemoGridI tem.FindControl ("tPriority" ),
TextBox).Text = "0" Then
CType(DemoGridI tem.FindControl ("tPriority" ),
TextBox).Text = ""
End If
Next

End Sub
the other problems i was having was due to a typo in my code when
naming the ID of the textbox in the grid. good grief :)

On Mon, 30 Jan 2006 09:40:36 -0600, "AMDRIT" <am****@hotmail .com>
wrote:

I would think it is better to ask the data container for zero length strings
and set the value to null from there.

my perferred way (barring stored procedures.)

for each dr as datarow in ctype(dbgdata.d atasource, datatable)
if not dr.isnull("Fiel dToCheck") andalso ctype(dr("Field ToCheck"),
string).length =0 then
dr.beginedit
dr("FieldToChec k") = system.dbnull.v alue
dr.endedit
end if
next

you can become even more specific by using

for each dr as datarow in ctype(dbgdata.d atasource,
datatable).get changes(Added or Modified)

Another thing you can try is to monitor when the selected row of a datagrid
changes.

private m_CurrentRowInd ex as integer
privatee m_CurrencyManag er as CurrencyManager

private sub form_load
m_CurrencyManag er =
ctype(me.bindi ngcontext(dbgda ta.datasource), currencymanager )

'Optionally issue
m_CurrencyManag er.Refresh
end sub

private sub m_CurrencyManag er_PositionChan ged(Sender, e) handles
m_CurrencyMana ger.PositionCha nged
'Todo: add logic if you allow column sorting....

if me.dbgDatga.Cur rentrowIndex <> m_currentrowind ex then

dim dr as datarow= ctype(dbgdata.d atasource,
datatable).row s(m_currentrowi ndex)

if not dr.isnull("Fiel dToCheck") andalso ctype(dr("Field ToCheck"),
string).length =0 then
dr.beginedit
dr("FieldToChec k") = system.dbnull.v alue
dr.endedit
end if

dbgDatga.Curren trowIndex = m_currentrowind ex

'Optionally issue
m_CurrencyManag er.Refresh

end if

end sub

"simon" <[e-mail]> wrote in message
news:hk******* *************** **********@4ax. com...

hello,
new to vb.net, have a few questions about DataGrid. I have a dataGrid
that is working pulling a dataset back from a stored proc and binding
to the datagrid for display
the datagrid's first column is a textbox(Templat eColumn), the other 3
columns are just display(BoundCo lumn).

(1) if the value of the textbox is 0, then i'd like to change it null,
so the box is empty

i tried this...

For Each PickGridItem In draftPickGrid.I tems
If Convert.ToInt16 (CType(PickGrid Item.FindContro l("tPriority" ),
TextBox).Text) = 0 Then
CType(PickGridI tem.FindControl ("tPriority" ), TextBox).Text = ""
End If
Next

this or variation of it didn't work. help?
(2) after the user click the button, I have a function that kicks off
that i wanted to loop the dataset, get a few values (one if which is
the textbox), and then call a proc to update the data

i tried this....

For Each DemoGridItem In draftPickGrid.I tems

EventId = Convert.ToInt16 (DemoGridItem.C ells(2).Text)
Priority =
Convert.ToInt16 (CType(DemoGrid Item.FindContro l("tPriority" ),
TextBox).Text)
DraftPicks.Upda teDraftPick(gro upID, EventId, userID, Priority)
Next

I was getting a "Object reference not set to an instance of an object"
on Priority

also tried these lines to capture the value of the textbox

Dim tb As TextBox
tb = DemoGridItem.Fi ndControl("tPri ority")
Priority = Convert.ToInt16 (tb.Text)

that didn't work either, same error

i'm using visual studio 2003 and put a break point on the function
that is called to loop and call the update proc, i have these
declaration lines at the top of the function

Dim EventId As Integer
Dim Priority As Integer
Dim DemoGridItem As DataGridItem
Dim DraftPicks As New DraftPicksDB
it will skip over the first three Dim lines, Dim the 4th and then move
to the for loop. in the loop when i hit the priority (textbox)
processing line the error is then thrown.

any help/advice would be appreciated - sample code is always welcome
:)
thanks in advance!