Discuss "populate datasource control from DDL" in the .Net Development forum.

richyrich · #11 (**permalink**) June 30th, 2008, 05:55 AM

Quote:

Originally Posted by Shem

@RR: what do you use if ya don't use datasource control?

I would use OnSelectedIndexChanged on the DDL and have a sub in code behind that handles the change and populates the other DDL rather than having a control within the page.

There's no reason why the datasource control method shouldn't work though...

Shem · #12 (**permalink**) June 30th, 2008, 06:09 AM

can you give me an example?

Shem · #13 (**permalink**) June 30th, 2008, 06:18 AM

narrowed the error down to where 'name' is being lost/blank

Code:

Private Shared Function FillDataRecord(ByVal myDataRecord As IDataRecord) As Zones
            Dim myZones As Zones = New Zones
            myZones.Idkey = myDataRecord.GetInt32(myDataRecord.GetOrdinal("idkey"))
            myZones.ProjectID = myDataRecord.GetInt32(myDataRecord.GetOrdinal("project_id"))
            myZones.UserID = myDataRecord.GetInt32(myDataRecord.GetOrdinal("userID"))
            myZones.Edited = myDataRecord.GetInt32(myDataRecord.GetOrdinal("edited"))
            myZones.Name = myDataRecord.GetString(myDataRecord.GetOrdinal("name"))
            myZones.Description = myDataRecord.GetString(myDataRecord.GetOrdinal("description"))
            HttpContext.Current.Response.Write("<br />name = " & myDataRecord.GetString(myDataRecord.GetOrdinal("name")) & "<br />")
            HttpContext.Current.Response.Write("idkey = " & myZones.Idkey & "<br />")
            Return myZones
        End Function

This is getting a value:

Code:

HttpContext.Current.Response.Write("<br />name = " & myDataRecord.GetString(myDataRecord.GetOrdinal("name")) & "<br />")

And this does not:

Code:

HttpContext.Current.Response.Write("<br />name = " & myZones.Name & "<br />")

Shem

Shem · #14 (**permalink**) June 30th, 2008, 06:31 AM

just tried this:

Code:

Public Property Name() As String
            Get
                HttpContext.Current.Response.Write("BO Name = " & _name)
                Return _name
            End Get
            Set(ByVal value As String)
                _name = value
            End Set
        End Property

It did NOT return a value

richyrich · #15 (**permalink**) June 30th, 2008, 06:33 AM

Quote:

Originally Posted by Shem

can you give me an example?

.aspx page

Code:

<asp:DropDownList id="DDL1" runat="server" autopostback="True" OnSelectedIndexChanged="DDL1_OnSelectedIndexChanged" />
 
<asp:DropDownList id="DDL2" runat="server" />

Code behind

Code:

Protected Sub DDL1_OnSelectedIndexChanged(ByVal s As Object, By Val e As EventArgs)
 
Dim conn as New MySQLConnection(ConnDal.ConnString)
Dim mycommand as New MySQLCommand("SELECT id,name FROM tbl WHERE primary_id=?id", conn)
Dim rs As MySQLDataReader
 
Try
       mycommand.Parameters.AddwithValue("id",DDL1.SelectedValue)
       conn.open
       rs = mycommand.ExecuteReader()
       if rs.HasRows then
           DDL2.DataSource=rs
           DDL2.DataValueField = "id"
           DDL2.DataTextField = "name"
           DDL2.DataBind()
       end if
       rs.close()
catch ex as Exception
       update_error.visible = True
       update_error.text = ex.ToString
finally
       mycommand.dispose()
       conn.close()
       conn.dispose()
end try
 
end sub

Quote:

Originally Posted by Shem

narrowed the error down to where 'name' is being lost/blank

My guess is it is an error between when you populate the Idkey value and when you populate the name value.

Try moving the myZones.Name code to right underneath the IdKey code.

Code:

myZones.Idkey = myDataRecord.GetInt32(myDataRecord.GetOrdinal("idkey"))
            myZones.Name = myDataRecord.GetString(myDataRecord.GetOrdinal("name"))
            myZones.ProjectID = myDataRecord.GetInt32(myDataRecord.GetOrdinal("project_id"))
            myZones.UserID = myDataRecord.GetInt32(myDataRecord.GetOrdinal("userID"))
            myZones.Edited = myDataRecord.GetInt32(myDataRecord.GetOrdinal("edited"))
            myZones.Description = myDataRecord.GetString(myDataRecord.GetOrdinal("description"))
            Return myZones
        End Function

Shem · #16 (**permalink**) June 30th, 2008, 06:42 AM

moving myZones.Name didn't help, but I have tested and it only populates
the integer fields and not the Text fields?

weird

richyrich · #17 (**permalink**) June 30th, 2008, 06:46 AM

Have you tried just using:-

Code:

If Not IsDBNull(myDataRecord("name")) then myZones.Name = myDataRecord("name")

That's what I use.

Shem · #18 (**permalink**) June 30th, 2008, 06:57 AM

didn't change a thing

man, this is frustrating the living heck outta me now!!!

richyrich · #19 (**permalink**) June 30th, 2008, 07:07 AM

Are you using MySQL or MS SQL?

I found

this on the MySQL website, but looks like it's all been resolved.

Would any of the records contain a NULL value for any of the fields you're returning?

jmurrayhead · #20 (**permalink**) June 30th, 2008, 07:30 AM

shem, try debugging your app: Walkthrough: Debugging Web Pages in Visual Web Developer

I would start off with setting a breakpoint on the FillDataRecord function and see if a value is actually being set or not.

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Discuss "populate datasource control from DDL" in the .Net Development forum.

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