I've been playing around with the new data controls (DetailsView,FormView) and have been having problems when attempting to update a record that has a uniqueidentifier as its primary key.

I get the error message:

Object must implement IConvertible.

Description: An unhandled exception occurred during the execution of the current web request. Please review the stack trace for more information about the error and where it originated in the code.

Exception Details: System.InvalidCastException: Object must implement IConvertible.

I gather this is because there is a bug that has propagated from the beta version.

One suggested work around is from
http://64.233.183.104/search?q=cache:GDjA62POtgcJ:scottonwriting.net/sowBlog/archive/11162005.aspx+Implicit+conversion+from+data+type+sql_variant+to+uniqueidentifier+is+not+allowed.+Use+the+CONVERT+function+to+run+this+query.&hl=en

The crux of the problem, it appears, is that the <asp:Parameter> value for the uniqueidentifier field is, by default, set to Type=”Object”. To fix this, simply remove the Type property altogether. That is, change the SqlDataSource parameter setting from something like:

<asp:SqlDataSource ...>
  <InsertParameters>
    <asp:Parameter Name=”UserId” Type=”Object” />
    ...
  </InsertParameters>
</asp:SqlDataSource>

to:

<asp:SqlDataSource ...>
  <InsertParameters>
    <asp:Parameter Name=”UserId”  />
    ...
  </InsertParameters>
</asp:SqlDataSource>

This change worked for me; once the Type was removed the exception ceased and the updates/inserts worked as expected.

Unfortunately this only partially worked for me as while it is fine for deletes it won't work for updates.

If anyone can help shed any light on this I would greatly appreciate it.

Cheers

Mark

Try Type Empty.

Unfortunately that didn't work.

Its just on the update I get the problem for some reason the delete and insert work fine.

My update stored procedure works fine on its own and the html fpr my sql datasource looks fine. (below)

<asp:SqlDataSource ID="sqlDSPotentialClients" runat="server" ProviderName="System.Data.SqlClient" ConnectionString="Data Source=STOCKHOLM\SQLSERVER2005;Initial Catalog=MembershipDemo;Integrated Security=True"

DeleteCommand="usp_tbl_potential_clients_delete" DeleteCommandType="StoredProcedure"

InsertCommand="usp_tbl_potential_clients_insert" InsertCommandType="StoredProcedure"

SelectCommand="usp_tbl_potential_clients_select_all" SelectCommandType="StoredProcedure"

UpdateCommand="usp_tbl_potential_clients_update" UpdateCommandType="StoredProcedure" >

<DeleteParameters>

<asp:ControlParameter ControlID="DetailsView" Name="id" PropertyName="SelectedValue" Type="Empty"/>

</DeleteParameters>

<UpdateParameters>

<asp:ControlParameter ControlID="DetailsView" Name="id" PropertyName="SelectedValue" Type="Empty"/>

<asp:ControlParameter ControlID="DetailsView" Name="company_name" PropertyName="SelectedValue" Type="String" />

<asp:ControlParameter ControlID="DetailsView" Name="trading_as" PropertyName="SelectedValue" Type="String" />

<asp:ControlParameter ControlID="DetailsView" Name="contact_title" PropertyName="SelectedValue" Type="Int32" />

<asp:ControlParameter ControlID="DetailsView" Name="contact_name" PropertyName="SelectedValue" Type="String" />

<asp:ControlParameter ControlID="DetailsView" Name="address1" PropertyName="SelectedValue" Type="String" />

<asp:ControlParameter ControlID="DetailsView" Name="address2" PropertyName="SelectedValue" Type="String" />

<asp:ControlParameter ControlID="DetailsView" Name="address3" PropertyName="SelectedValue" Type="String" />

<asp:ControlParameter ControlID="DetailsView" Name="address4" PropertyName="SelectedValue" Type="String" />

<asp:ControlParameter ControlID="DetailsView" Name="postcode" PropertyName="SelectedValue" Type="String" />

<asp:ControlParameter ControlID="DetailsView" Name="phone" PropertyName="SelectedValue" Type="String" />

<asp:ControlParameter ControlID="DetailsView" Name="fax" PropertyName="SelectedValue" Type="String" />

<asp:ControlParameter ControlID="DetailsView" Name="lead" PropertyName="SelectedValue" Type="Boolean" />

</UpdateParameters>

<InsertParameters>

<asp:ControlParameter ControlID="DetailsView" Name="company_name" PropertyName="SelectedValue" Type="String" />

<asp:ControlParameter ControlID="DetailsView" Name="trading_as" PropertyName="SelectedValue" Type="String" />

<asp:ControlParameter ControlID="DetailsView" Name="contact_title" PropertyName="SelectedValue" Type="Int32" />

<asp:ControlParameter ControlID="DetailsView" Name="contact_name" PropertyName="SelectedValue" Type="String" />

<asp:ControlParameter ControlID="DetailsView" Name="address1" PropertyName="SelectedValue" Type="String" />

<asp:ControlParameter ControlID="DetailsView" Name="address2" PropertyName="SelectedValue" Type="String" />

<asp:ControlParameter ControlID="DetailsView" Name="address3" PropertyName="SelectedValue" Type="String" />

<asp:ControlParameter ControlID="DetailsView" Name="address4" PropertyName="SelectedValue" Type="String" />

<asp:ControlParameter ControlID="DetailsView" Name="postcode" PropertyName="SelectedValue" Type="String" />

<asp:ControlParameter ControlID="DetailsView" Name="phone" PropertyName="SelectedValue" Type="String" />

<asp:ControlParameter ControlID="DetailsView" Name="fax" PropertyName="SelectedValue" Type="String" />

<asp:ControlParameter ControlID="DetailsView" Name="lead" PropertyName="SelectedValue" Type="Boolean" />

</InsertParameters>

</asp:SqlDataSource>

I've traced it in the sql profiler and the update doesn't get that far so its not a database issue.

Any help would be great as I am stumped.

Mark

I think the issue might partially be a bug in the SqlDataSource control (someone else founds it not too long ago, if I recall).

I'm pretty sure that the workaround was to handle the "pre" event for the operation (e.g. Updating) and set the DbType manually:

e.Command.Parameters["myguidparam"].DbType = DbType.Guid;

And that solves the problem. It's unfortunate that the TypeCode enum (which is what Parameter uses for its Type property) doesn't have a Guid value.

Thanks,

Eilon

Thanks for the suggestion Eilon.

Unfortunately the DetailsViewUpdateEventArgs (and FormViewUpdateEventArgs) don't contain a definition for command. Using the following code

protected void DetailsView_ItemUpdating(object sender, DetailsViewUpdateEventArgs e)

{

e.Command.Parameters["id"].DbType = DbType.Guid;

}

I get the error below:

Error 387 'System.Web.UI.WebControls.DetailsViewUpdateEventArgs' does not contain a definition for 'Command'

It looks like the DetailsViewUpdateEventArgs (and FormViewUpdateEventArgs) only allow Get access to the public properties.

Any other suggestions would be greatly appreciated.

Regards

Mark

 

Sorry about that, I should have been more specific. I meant to handle the data source's Updating event (SqlDataSource.Updating), not the data bound control.

 

Thanks,

Eilon

Thanks for the reply Eilon,

Unfortunately that still doesn't work .

I added the event to the sqldatasource as you suggested.

protected void sqlDSPotentialClients_Updating(object sender, SqlDataSourceCommandEventArgs e)

{

e.Command.Parameters["id"].DbType = DbType.Guid;

}

And I put a breakpoint on it but the exception throws before the breakpoint is hit.

I've attached the stack trace below

[InvalidCastException: Object must implement IConvertible.]
   System.Convert.ChangeType(Object value, TypeCode typeCode, IFormatProvider provider) +2562898
   System.Web.UI.WebControls.Parameter.GetValue(Object value, String defaultValue, TypeCode type, Boolean convertEmptyStringToNull, Boolean ignoreNullableTypeChanges) +257
   System.Web.UI.WebControls.Parameter.get_ParameterValue() +92
   System.Web.UI.WebControls.ParameterCollection.GetValues(HttpContext context, Control control) +282
   System.Web.UI.WebControls.SqlDataSourceView.InitializeParameters(DbCommand command, ParameterCollection parameters, IDictionary exclusionList) +344
   System.Web.UI.WebControls.SqlDataSourceView.ExecuteUpdate(IDictionary keys, IDictionary values, IDictionary oldValues) +451
   System.Web.UI.DataSourceView.Update(IDictionary keys, IDictionary values, IDictionary oldValues, DataSourceViewOperationCallback callback) +179
   System.Web.UI.WebControls.DetailsView.HandleUpdate(String commandArg, Boolean causesValidation) +1199
   System.Web.UI.WebControls.DetailsView.HandleEvent(EventArgs e, Boolean causesValidation, String validationGroup) +545
   System.Web.UI.WebControls.DetailsView.OnBubbleEvent(Object source, EventArgs e) +162
   System.Web.UI.Control.RaiseBubbleEvent(Object source, EventArgs args) +56
   System.Web.UI.WebControls.DetailsViewRow.OnBubbleEvent(Object source, EventArgs e) +117
   System.Web.UI.Control.RaiseBubbleEvent(Object source, EventArgs args) +56
   System.Web.UI.WebControls.LinkButton.OnCommand(CommandEventArgs e) +106
   System.Web.UI.WebControls.LinkButton.RaisePostBackEvent(String eventArgument) +175
   System.Web.UI.WebControls.LinkButton.System.Web.UI.IPostBackEventHandler.RaisePostBackEvent(String eventArgument) +31
   System.Web.UI.Page.RaisePostBackEvent(IPostBackEventHandler sourceControl, String eventArgument) +32
   System.Web.UI.Page.RaisePostBackEvent(NameValueCollection postData) +242
   System.Web.UI.Page.ProcessRequestMain(Boolean includeStagesBeforeAsyncPoint, Boolean includeStagesAfterAsyncPoint) +3840

If you have any further ideas that would be great.

Cheers

Mark

Hi Eilon

Is there any resoluton to this problem above?

Thanks
Gregor

Any update on this Eilon?

Ta
Gregor

Instead of DBType.Guid, try sqldbtype.uniqueidentifier

Have you tried something like this?

    protected void Page_Load(object sender, EventArgs e)
    {
        FormView1.ItemUpdating += new FormViewUpdateEventHandler(FormView1_ItemUpdating);
    }

    protected void FormView1_ItemUpdating(object sender, FormViewUpdateEventArgs e)
    {
        IOrderedDictionary values = e.NewValues;
        String key = "id";

        if ( values.Contains(key) )
        {
            String id = String.Format("{0}", values[key]);
            values.Remove(key);
            values.Add(key, new Guid(id));
        }
    }

did this get resolved I am having the same issue

Nope I'm afraid not - was hoping it would have by now.

Cheers
Gregor

Gregor

Did you happen to try what I suggested on 27-Feb-2006?

Bobby

i got the result.

that is uniqueidentifier is a STRING Type.

when you try  to change that parameter like <Parameter Name=***, Type= String >

 

it must work.

 

:D

 

But one problem i comes that is , in sql 2000, it shows that there is only a typ called bit

But in VS2005,there is a type called boolean.,

 

THey cannot change to each other. and i faced the same caution that Object must implement IConvertible

 

。。。。。。

So, who can solve?