Set ImageButton.ImageUrl

aspless · August 26th, 2011, 06:54 PM

Chaps..

I am hoping i'm not to far off on this one..

I am reading a value from a datasource and based on a simple bit value wish to alter the ImageButton.ImageUrl associated with a gridview.

The Gridview Variables are:

Code:

 
<asp:GridView ID="GridView1" DataSourceID="SqlDataSource1" ect ect>
<asp:TemplateFieldHeaderText="Sub Groups">
<ItemTemplate>
<asp:ImageButtonID="ImgButGridGroup"runat="server"CausesValidation="false"CommandName="showSubGroups"ImageUrl="~/images/icons/gridgroups.jpg"Text="Button"/>
</ItemTemplate>
</asp:TemplateField>

My VB Code is

Code:

ProtectedSub Page_Load(ByVal sender AsObject, ByVal e As System.EventArgs) HandlesMe.Load
Dim dvSql AsDataView = DirectCast(SqlDataSource1.Select(DataSourceSelectArguments.Empty), DataView)
ForEach drvSql AsDataRowViewIn dvSql
Dim SubGrpImgVal AsInteger = drvSql("subgroupimg").ToString
Dim ImgButGridGroup AsImageButton = CType(GridView1.FindControl("ImgButGridGroup"), ImageButton)
If SubGrpImgVal = 1 Then
ImgButGridGroup.ImageUrl = "~/images/icons/gridmembers.jpg"
Else
ImgButGridGroup.ImageUrl = "~/images/background/1pxWhiteSpace.jpg"
EndIf
NextEndSub

As far as i can tell from the debug watch the datasource value is comming through fine..

The error i am getting is

Code:

Object reference not set to an instance of an object

Which indicates that there is a mismatch but can't see what part of the ImageButton reference is not working.

Still very much getting to grips with VB..

Any assist would be appreciated!!

Cheers

Aspless

aspless · August 26th, 2011, 07:42 PM

Ok .. Now seeing that i am not getting any value from
dvSql

Latest effort is

Code:

Dim dvSql AsDataView = DirectCast(SqlDataSource1.Select(DataSourceSelectArguments.Empty), DataView)
Dim index AsInteger = GridView1.SelectedIndex
ForEach drvSql AsDataRowViewIn dvSql
index = 0
Dim SubGrpImgVal AsInteger = drvSql("subgroupimg").ToString
If SubGrpImgVal = 1 Then
Dim ImgButGridGroup AsImageButton = CType(GridView1.Rows(index).FindControl("ImgButGridGroup"), ImageButton)
ImgButGridGroup.ImageUrl = "~/images/icons/gridmembers.jpg"
Else
Dim ImgButGridGroup AsImageButton = CType(GridView1.Rows(index).FindControl("ImgButGridGroup"), ImageButton)
ImgButGridGroup.ImageUrl = "~/images/background/1pxWhiteSpace.jpg"
EndIf
index = index + 1
Next

Which essentially removes the image from row 1 and as there is no data being returned i'm not supprised ..

First time i have tried to extract from the Datasource so that does not help!

Thoughts?

aspless · August 26th, 2011, 08:52 PM

Ok ..

After further testing i am getting data out of the sqldatasource1 running the following script:

Code:

Dim dvAccess AsDataView = DirectCast(SqlDataSource1.[Select](DataSourceSelectArguments.Empty), DataView)
Label1.Text = dvAccess(0)(4).ToString() & "<br>"
Label2.Text = dvAccess(1)(4).ToString() & "<br>"
Label3.Text = dvAccess(2)(4).ToString() & "<br>"
Label4.Text = dvAccess(3)(4).ToString() & "<br>"

Could someone do me the small favour of helping me get this into a proper Loop through the data.

aspless · August 26th, 2011, 09:55 PM

Making progress and just need to get the index working properly

Any nudge?

Code:

Dim dvAccess AsDataView = DirectCast(SqlDataSource1.[Select](DataSourceSelectArguments.Empty), DataView)
Dim index AsInteger'= GridView1.SelectedIndex
index = 0
ForEach rowView AsDataRowViewIn dvAccess
'Create(index)
If index = 0 Then
index = 1
Else
index = index + 1
EndIf
Dim row AsDataRow = rowView.Row ' Do something '
Label1.Text = row(4)
If row(4) = 1 Then
Dim ImgButGridGroup AsImageButton = CType(GridView1.Rows(index).FindControl("ImgButGridGroup"), ImageButton)
ImgButGridGroup.ImageUrl = "~/images/icons/gridmembers.jpg"
Else
Dim ImgButGridGroup AsImageButton = CType(GridView1.Rows(index).FindControl("ImgButGridGroup"), ImageButton)
ImgButGridGroup.ImageUrl = "~/images/background/1pxWhiteSpace.jpg"
EndIf
　
Next