Retrieving selected gridview column values for SQLDatasource asp:controlparameters

Not sure if this is the correct forum, but I 'm having problems retrieving a sqldatasource's asp:control parameter values from a selected row (during edit) in a gridview to update a record thru a stored procedure. The stored procedure is pretty intense, so I'd like to keep it in SQL if possible instead of creating the generic "update table set ..." that I see in most examples. It seems as if I can't get the propertyname right or something because it keeps giving me a "Procedure or function XX has too many arguments specified error". Maybe the DataKeyNames is not right?? I've tried just passing one parameter (ProductID-same as DataKeyNames) using "SelectedValue" as propertyname and still get the same. It's got to be something very simple, but I'm at a loss. All parameters are spelled the same in the sp (with an added "@." at start) as in the asp:controlparameters. Here's the gridview (asp.net 2.0 connecting to SQL Server 2005):

<

asp:GridViewID="gvLoadEditProductPrices"runat="server"AutoGenerateColumns="False"AllowSorting="True"DataSourceID="SqlDataSource1"DataKeyNames="ProductID"><Columns><asp:CommandFieldShowEditButton="True"/><asp:BoundFieldDataField="ProductID"HeaderText="ProductID"HeaderStyle-BackColor="white"InsertVisible="False"ReadOnly="True"SortExpression="ProductID"/><asp:BoundFieldDataField="Product"HeaderText="Product"SortExpression="Product"ReadOnly="True"/><asp:BoundFieldDataField="ProductCat"HeaderText="ProductCat"SortExpression="ProductCat"ReadOnly="True"/><asp:BoundFieldDataField="VarRate"HeaderText="VarRate"SortExpression="VarRate"/><asp:BoundFieldDataField="loadid"HeaderText="loadid"InsertVisible="False"ReadOnly="True"SortExpression="loadid"/><asp:BoundFieldDataField="loadamount"HeaderText="loadamount"SortExpression="loadamount"ReadOnly="True"/><asp:BoundFieldDataField="ProductCol"HeaderText="ProductCol"SortExpression="ProductCol"ReadOnly="True"/><asp:BoundFieldDataField="PageID"HeaderText="PageID"SortExpression="PageID"ReadOnly="True"/></Columns></asp:GridView>

and the sqldatasource's info:

<

asp:SqlDataSourceID="SqlDataSource1"runat="server"ConnectionString="<%$ ConnectionStrings:MARSProductEditor %>"ProviderName="System.Data.SqlClient"SelectCommand="spGetLoadEditProductPrices"SelectCommandType="StoredProcedure"UpdateCommand="spUpdateProductPrices"UpdateCommandType="StoredProcedure"><UpdateParameters><asp:ControlParameterName="ProductID"Type="Int32"ControlID="gvLoadEditProductPrices"PropertyName=SelectedDataKey.Values("ProductID")></asp:ControlParameter><asp:ControlParameterName="LoadID"Type="Int32"ControlID="gvLoadEditProductPrices"PropertyName=SelectedDataKey.Values("LoadID")></asp:ControlParameter><asp:ControlParameterName="PageID"Type="Int32"ControlID="gvLoadEditProductPrices"PropertyName=SelectedDataKey.Values("PageID")></asp:ControlParameter><asp:ControlParameterName="ProductCol"Type="Int32"ControlID="gvLoadEditProductPrices"PropertyName=SelectedDataKey.Values("ProductCol")></asp:ControlParameter><asp:ControlParameterName="NewRate"Type="Double"ControlID="gvLoadEditProductPrices"PropertyName=SelectedDataKey.Values("NewRate")></asp:ControlParameter></UpdateParameters><SelectParameters><asp:ControlParameterControlID="ddlEstLoadsPerAcre"Name="LoadID"PropertyName="SelectedValue"Type="Int32"/><asp:ControlParameterControlID="txtEditType"Name="PageName"PropertyName="Text"Type="String"/></SelectParameters></asp:SqlDataSource>

TIA,

John

Nevermind...after hours of testing many different combinations and scenarios, I found that I had to add each field that the control parameter needs to reference in the gridview to the "DataKeyNames" property in the gridview. But, any field I wanted to be updated thru the gridview edit had to use the PropertyName="SelectedValue" as opposed to the PropertyName="SelectedDataKey.Values('fieldname')". I also had to use single quotes for the field name.

John

Retrieving an image from SQL, test for null

I have an employee directory application that displays employees in a gridview. When a record is selected, a new page opens and displays all info about the employee, including their photo. I have the code working that displays the photos, however, when no photo is present an exception is thrown that "Unable to cast object of type System.DbNull to System.Byte[]". I'm not sure how to test for no photo before trying to write it out.

My code is as follows (with no error trapping):

PrivateSub Page_Load(ByVal senderAs System.Object,ByVal eAs System.EventArgs)HandlesMyBase.Load,Me.Load

Dim tempAsString

Dim connPhotoAs System.Data.SqlClient.SqlConnection

Dim connstringAsString

connstring = Web.Configuration.WebConfigurationManager.ConnectionStrings("connPhoto").ConnectionString

connPhoto =New System.Data.SqlClient.SqlConnection(connstring)

temp = Request.QueryString("id")

Dim SqlSelectCommand2As System.Data.SqlClient.SqlCommand

Dim sqlstringAsString

sqlstring ="Select * from dbo.PhotoDir WHERE (CMS_ID = " + temp +")"

SqlSelectCommand2 =New System.Data.SqlClient.SqlCommand(sqlstring, connPhoto)

Try

connPhoto.Open()

Dim myDataReaderAs System.Data.SqlClient.SqlDataReader

myDataReader = SqlSelectCommand2.ExecuteReader

DoWhile (myDataReader.Read())

Response.BinaryWrite(myDataReader.Item("ImportedPhoto"))

Loop

connPhoto.Close()

Catch SQLexecAs System.Data.SqlClient.SqlException

Response.Write("Read Failed : " & SQLexec.ToString())

EndTry

EndSub

EndClass

If you could point me in the right direction I would appreciate it.

lwhalen618:

when no photo is present an exception isthrown that "Unable to cast object of type System.DbNull toSystem.Byte[]

lwhalen618:

DoWhile (myDataReader.Read())

Response.BinaryWrite(myDataReader.Item("ImportedPhoto"))

Loop

did you try to check for nulls ??

DoWhile (myDataReader.Read())
if Not IsDBNull(myDataReader.Item("ImportedPhoto")) then
Response.BinaryWrite(myDataReader.Item("ImportedPhoto"))
End if
Loop

hope it works... pls let me know

Good Luck./.

|||

I did try testing for null but was doing it incorrectly. Your code worked fine. Thanks!

retrieve data from the gridview

i need to retrieve data from a particular field of the gridview according to the selected row to stored it into session ....

what i had done so far as following:

Protected Sub GridView1_SelectedIndexChanged(ByVal sender As Object, ByVal e As System.EventArgs)
DetailsView1.PageIndex = GridView1.SelectedIndex
Session.Add("receiverName", GridView1.??)

End Sub

??? is the part i am not sure what to code... i tried different method by seems to have problem of convertion.

You can access the seleced row of gridview by using the SelectedRows property, see:

http://msdn2.microsoft.com/en-us/library/system.windows.forms.datagridview.selectedrows(d=ide).aspx