Thanks,
Bill

Not good.  In another post today, I explored the issue of limiting my data being presented to the user because of bandwidth constraints. One way for me to do this easily would be to simply set a filter on one of the custom properties of the BO.  Since I cannot do this, my problem has become gargantuan.  Since the property is there, there must be a way to do this kind of filtering.  I cannot give up, yet.

Let me make sure I get this....if I had a customer business object with a really cool custom property like TotalOrders, it is impossible for me using that custom property to display all customers with more than 100 orders.  Is that right?

I am starting to see that.  Nevertheless, I am still quite confused about the custom property thing.  To me, the business object is an ideal place for some of these things.  The database is not the best location.  You and Trent are suggesting that I need to relocate the business logic back into the database.

Here is an example of some custom properties on the Parts business object that I have (declarations/tags/comments removed for brevity):

public int OnWorkOrder
{
    get
    {
        string mPartindex = this.partindex.ToString();
        return (int)ExecuteScalar("spx_GetAmountOnWorkOrder '" + mPartindex + "'");
    }
}

public int OnSalesOrder
{
    get
    {
        string mPartindex = this.partindex.ToString();
        return (int)ExecuteScalar("spx_GetAmountOnSalesOrder '" + mPartindex + "'");
    }
}

public int RequiredQty
{
    get
    {
        int mReqQty = (this.minstocklevel - this.onhandqty) + (this.OnSalesOrder - this.OnWorkOrder);
        if (mReqQty < 0) mReqQty = 0;
        return mReqQty;
    }
}

As you can see, the logic becomes rather complex.  Easily handled in the business object.  The stored procedure that would handle this same stuff would be atrocious...doable, but a near nightmare to construct.  I really do not want to put all this back into the DB.  If I do, then these custom properties become unneeded.  In fact, I cannot see a good use for custom properties, since all of this can be done in the DB.

Bill

ArgumentException
  An item with the same key has already been added.

Source     : mscorlib

Stack Trace:
   at System.ThrowHelper.ThrowArgumentException(ExceptionResource resource)
   at System.Collections.Generic.Dictionary`2.Insert(TKey key, TValue value, Boolean add)
   at MicroFour.StrataFrame.UI.Windows.Forms.BrowseDialogSearchingEventArgs..ctor(BrowseDialog Browse, WhereStatementCollection WhereStatements)
   at MicroFour.StrataFrame.UI.Windows.Forms.BrowseDialogwindow.ExecuteSearch()
   at MicroFour.StrataFrame.UI.Windows.Forms.BrowseDialogwindow.tsiSearch_Click(Object sender, EventArgs e)
   at System.Windows.Forms.ToolStripItem.RaiseEvent(Object key, EventArgs e)
   at System.Windows.Forms.ToolStripButton.OnClick(EventArgs e)
   at System.Windows.Forms.ToolStripItem.HandleClick(EventArgs e)
   at System.Windows.Forms.ToolStripItem.HandleMouseUp(MouseEventArgs e)
   at System.Windows.Forms.ToolStripItem.FireEventInteractive(EventArgs e, ToolStripItemEventType met)
   at System.Windows.Forms.ToolStripItem.FireEvent(EventArgs e, ToolStripItemEventType met)
   at System.Windows.Forms.ToolStrip.OnMouseUp(MouseEventArgs mea)
   at System.Windows.Forms.Control.WmMouseUp(Message& m, MouseButtons button, Int32 clicks)
   at System.Windows.Forms.Control.WndProc(Message& m)
   at System.Windows.Forms.ScrollableControl.WndProc(Message& m)
   at System.Windows.Forms.ToolStrip.WndProc(Message& m)
   at System.Windows.Forms.Control.ControlNativewindow.OnMessage(Message& m)
   at System.Windows.Forms.Control.ControlNativewindow.WndProc(Message& m)
   at System.Windows.Forms.Nativewindow.Callback(IntPtr hWnd, Int32 msg, IntPtr wparam, IntPtr lparam)

Thought I had something there...I was going to plop a browsedialog on the form and force the user to work through that (with the custom property set to not visible).  Not sure what that error means, but I assume it is saying, "Uh uh uh!".  That won't work, I guess.

While our apps are not 'net based I think our general approach could be useful to you:

1) We have a BO for a particualar table. In this exaple the PUN (Packing Unit) table.

2) This BO has number of methods that are used to retrieve data. In the example below it is calling a proc that returns data just for a specific Station Type (which isn't part of the PUN table) and if the PUN is in stock or not and the order in which we want to data to be returned. In our case stp_boPUN is very generic and extracts and sorts data in various ways depending what parameters are passed in

    ' Populate the BO with all in stock PUNs for a specific station type.
    Public Sub GetPUNInStock(ByVal StationType As String)

        Dim ProcParam(2) As System.Data.SqlClient.SqlParameter
        ProcParam(0) = New System.Data.SqlClient.SqlParameter
        With ProcParam(0)
            .ParameterName = "@INSStationType"
            .DbType = Data.DbType.String
            .Direction = Data.ParameterDirection.Input
            .Value = StationType
        End With
        ProcParam(1) = New System.Data.SqlClient.SqlParameter
        With ProcParam(1)
            .ParameterName = "@InStock"
            .DbType = Data.DbType.Boolean
            .Direction = Data.ParameterDirection.Input
            .Value = 1
        End With
        ProcParam(2) = New System.Data.SqlClient.SqlParameter
        With ProcParam(2)
            .ParameterName = "@OrderBy"
            .DbType = Data.DbType.Int16
            .Direction = Data.ParameterDirection.Input
            .Value = 1
        End With

        Dim cmd As New SqlCommand
        cmd.CommandType = Data.CommandType.StoredProcedure
        cmd.CommandText = "stp_boPUN"
        cmd.Parameters.AddRange(ProcParam)

        Me.TMSFillUsingCommand(cmd)
        cmd.Dispose()
    End Sub

3) Me.TMSFillUsingCommand(cmd) is executed to fill the PUN BO with just the data we want.

4) Me.TMSFillUsingCommand is just a wrapper we have for all our DAL code that does things like error handling / retries etc. The main point is that, in the end, it executes the standard SF fill method using a command string.

5) In our form we would execute Me.boPUN.GetPUNInStock(StationType) and that's it. If the BO was the basis for a grid (we use DevExpress) the grid is automatically refreshed with the new data set.

Bottom line is that we use specific stored procs to do the work and only return the data we want.

Cheers, Peter

I really appreciate the response.  The approach you have outlined is quite good.  I would employ a similar approach if I am forced to utilize a bank of stored procedures to create every data property of my business object.  I shiver at the prospect. 

I am valiantly trying to get a custom property to work in my favor.  Perhaps I am not handling the business object in the right fashion and expecting way too much from it.  It would be nice to not have to deal with the data layer when working with the existing business objects.  I am hoping that there is still a way to handle custom properties without resorting to stored procedures and views.

Thanks,
Bill

foreach (DataRow dr in this.CurrentDataTable.Rows)
{
    if (this.RequiredQty = 0)
    {
        this.CurrentRow.Delete();
    }
}

I would run this immediately after I perform the FillDataTable method on the BO.  The Delete method would only delete the row from the CurrentDataTable...it wouldn't mark it for deletion and drop it from the database, right?

I could see an initial speed hit at the time of filling the BO, but not when the user is performing their own sorts, groupings and such on the corresponding DX datagrid.  Would this work?

Thanks,
Bill

The sp's in my code were placed in there for initial testing and I never removed them.  My goal was to replace them with calls to the corresponding business objects (which were not created at the time--they exist now). 

I am following you.  Really.  The thing that I am tripping up on is that once I give the DB the job of creating my custom properties (which are not custom properties to the business object anymore...they are actually columns in the remote data table) there remains little benefit to be derived from a custom property in the business object itself.

Well, getting late.  Time to go home.  Got an early and long day tomorrow.

Take care,
Bill

No need to do this - the proc can return whatever you want. I my example the StationType was just part of the WHERE clause but the value being checked was in an associated table not the PUN table itself.

In our PUN table for example we have quite a number of custom fields:

    Protected Overrides Function GetCustomBindablePropertyDescriptors() As MicroFour.StrataFrame.Business.FieldPropertyDescriptor()

        Dim boPUNType As System.Type = Me.GetType()

        Return New MicroFour.StrataFrame.Business.FieldPropertyDescriptor() { _
             New MicroFour.StrataFrame.Business.ReflectionPropertyDescriptor( _
            "OperatorName", boPUNType), _
             New MicroFour.StrataFrame.Business.ReflectionPropertyDescriptor( _
            "INIDescription", boPUNType), _
             New MicroFour.StrataFrame.Business.ReflectionPropertyDescriptor( _
            "INIMaxHides", boPUNType), _
             New MicroFour.StrataFrame.Business.ReflectionPropertyDescriptor( _
            "INIMaxWeight", boPUNType), _
             New MicroFour.StrataFrame.Business.ReflectionPropertyDescriptor( _
            "INIMaxArea", boPUNType), _
            New MicroFour.StrataFrame.Business.ReflectionPropertyDescriptor( _
            "PKBCode", boPUNType), _
            New MicroFour.StrataFrame.Business.ReflectionPropertyDescriptor( _
            "ReceiveBatchCode", boPUNType), _
            New MicroFour.StrataFrame.Business.ReflectionPropertyDescriptor( _
            "FlesherBatchCode", boPUNType), _
            New MicroFour.StrataFrame.Business.ReflectionPropertyDescriptor( _
            "ShortTermBatchCode", boPUNType), _
            New MicroFour.StrataFrame.Business.ReflectionPropertyDescriptor( _
            "TanningBatchCode", boPUNType)}
    End Function

#End Region

Our stored procedures return these values as needed. If we need to add more custom fields we can without breaking any existing code.

Regarding the other question - correct it wouldn't actually delete the rows until you did a BO.Save so you would want to carefull.

The best approach is not to return the data at all.

Cheers, Peter

Thanks so much for an very very useful example.  Coming from a VFP and Visual FoxExpress background I'm very used to thinking in terms of dynamic view parameters and only bringing as many records over the wire as absolutely necessary.  I'm very new to Strataframe and .NET in general and your code has helped a lot to translate some familiar concepts and give me a lot of ideas as to how I want to use the Strataframe framework.

Stuff like this always very much appreciated. 

Actually, no.  There has been a lot of good dialog come from this post and this alone should be evident that there are many different ways to approach a problem.  First of all, if you create a custom property and want to sort on that property, there has to be an underlying column in the CurrentDataTable....you can, as you have seen from Greg and others, pull a faux field as part of your query....or in the CurrentDataRefilled event of your BO, you could progammatically add the columns into the CurrentDataTable so that you could filter on this as well:

You could then, in your custom property, store off the value in the Set (or even the Get of the proper if it is readonly):

Taking this approach you could then sort and filter on the aggregate field.

Thanks, Peter!  I will review your code a bit more to see if I may be missing something. 

Can a user search on these custom fields (e.g. OperatorName="Bill") using the BrowseDialog?  Or, could I use code to sort on one of these fields (e.g. myBO.Sort = "INIMaxWeight DESC")?

Regards,
Bill

Yes, but this will also make the BO dirty and if you do not want the table to be updated back at the server, you will have to AcceptChanges on the CurrentDataTable...otherwise this will be deleted from the server if a Save() is called:

Trent,

I have been known to be quite dense at times.  Sometimes saying something slightly differently fires certain synapses and things start clicking.  For me, it was the word "faux".  Thanks for pulling out the French.  English just wasn't getting through to me.

I will see what I can do with the creation of columns in an sp for the use with my custom properties.  Also, I need to spend some more time with Peter's code.  Looks like a good morning ahead.

Thanks, everyone, for your patience with me.
Bill

No.  The BrowseDialog creates Dynamic queries that are placed against the Database on the server, not the BO.  The BO is not where the query takes place....if you think about it, if the BO were where the query occurred, you would never pull any records back from the server.  So in this instance you will never be able to query on a custom property (unless it has an underlying field on the server that can be queried).

No problem

Took a while for me to readdress this issue.  I am hitting another brick wall.  I tried adding the column in the method.  If I run a search on the BO, the CurrentDataTable gets refilled again and the column is tried to be readded.  Pop!  Error.  So, I'll check for existence of the column before adding it.

Also, setting the aggregate field to the value of the custom property is tripping me up.  Your VB "Me.Item("MyAggregateField")" is not translating for me in my C# world.  Please let me know where I can access that collection(?). 

Thanks!!
Bill

or you could talk straight to the current row:

Man, I am getting tired...past midnight here.  Still struggling with this, though.  Looks like I will have to get back to this later.  Gotta sleep.

No Mountain Dew in the house. 

I'll get back with you "tomorrow."
Bill

CurrentDataTable.Columns.Add("colReqQty", typeof(decimal));

I am checking for the existence before adding.  I then set a filter on the BO to something like this:

MyBO.Filter = "colReqQty > 0";

Nothing.  As a matter of fact, I am getting no value for my Custom Property, at all (named "spxRequiredQty").  Here is my code for the custom property:

I should be able to see a column called [colReqQty] in my BO; however, it does not show up.  For example, I cannot add it to a grid via a BBS.

At the moment, I am quite confused.

decimal mReqQty = (this.minstocklevel - this.onhandqty) + (this.spxSalesOrderQty - this.spxWorkOrderQty);

What am I doing wrong?  Since the actual custom property is not getting "filled" then the value of my additional column will never get updated.  Therefore, my filter will not work.

This is just viscious! 

  <--- see I am still smiling!!

Perhaps I did not get enough sleep last night.

Thanks a ton, Greg!
Bill

There are three custom properties and one additional column (for the filter).  Prop3 = Prop2 - Prop1 (basically), then ColumnA = Prop3.  Filter ColumnA so that only values greater than 0 are shown.

Looping through the BO is very time consuming...several minutes to kerchunk each custom prop, then display the grid.  Not a good option.  In addition, the filter did not work even though the column has data!  It shows on the grid.  None of the custom properties show up on the grid...all blank still.

That seems to only affect the first row of the BO. 

Both of these last two options made the BO dirty.  Closing the window asked me if I want to save changes.

This is an option (and I have done this for several other BOs)...but, the complexity of the stored procs and UDFs would make the process so slow and painful that it just isn't fun anymore.  Placing the complex code inside of custom class and/or business object really, really makes things a LOT easier (cleaner and neater, too). 

Well, back to the drawing board.  And, in the immortal words of Bill the Cat:

ACK!

I think that you are trying to make this too complicated.  I think that I would first backup and then start rethinking through your process.

First, we use custom columns as aggregates OR create a custom property that dynamically returns aggregates a lot.  Now since you are trying to apply a filter, then you will most likely want a column in the data table.

OK.  Since we have that established, from what I can understand, you always want to have a calculated column within your data table.  So obviously if you perform a query, then you can do this as part of the query (easier and faster in some cases).  However, if you will have a scenario that will not retrieve data from a database query first, then you would need to ensure that the column gets manually added prior to being refrenced or accessed.  So in this case, I would do one of two things to ensure that the column exists within the BO.

1. Override the OnAfterAddNew method of the BO and ensure that the desired columns get added within the BO and/or exist when a new record is added.  This way a query is not required, but when you add a new record the BO will ensure that the column exists.
2. Override the OnCurrentDataTableRefilled method of the BO and call the same logic that is added as part of the OnAfterAddNew method.

By doing the above two things you will always be ensured that you have the column within your data table, thus allowing a filter to be applied.

At this point, you will just create the custom property on the BO to access it through the strong-typed reference, but you can then treat this column just as though you could any other column that comes from the database, however, it just resides within the BO.

From these custom properties, I would like to filter the grid on the spxRequiredQty value.  Somehow, I have to tell the underlying table of the BO that the column exists and what the data actually is (without resorting to stored procs and such). 

I know I am being difficult with this.  I have tried so many things that all of this is becoming a blur.  I have read through this thread several times, but just cannot see the light.  Thought I did a few times, but it was just that proverbial debug train coming at me through the tunnel of code exceptions.

Bill

P.S. Still using SQL Server 2000. 

Try taking the business binding source out of the equation, just throw a few text boxes on a form bound to your business object custom properties  fill it and navigate through your record set and see if it works.

The business binding source can create some serious migraine style headaches as it creates a new instance of the business object for each row so some things that have been set in the original BO are not longer "set" in the newly created bo.. Try it withough the BBS and see if your logic works. 

If it works without the BBS in the middle then you can play doctor with the BBS source code and create a BBS specific to the business object you are binding to.

Paul

Just in case it might help you see what Trent told you about adding a new field to your table and filtering on it, here is some code of mine where I do exactly the same, filtering on a field that doesn't exist on the underlying table.

On your BO:

And, of course, the property:

So, now, on my logic, after setting my field depending on conditions:

Hope it helps in some way...

The grid has a BBS datasource that points to the exact same BO.  All of the fields in the grid are blank.

(preparing to look for a towel to throw in)

Thanks for the input.  The only real difference is that my properties are read-only; therefore, no set portion.  I have done exactly what you did...except I did not put the add column code in both methods of the BO (initialize and refilled).  I will try that.

Bill

What happens when you use a BBS is that it creates a new instance of the busines object for every row. However it does not carry over any custom properties etc that are to the new instance.for instance if you have a property called foo in you business object and its value has been set to "Something" what the business binding source create a new instance of the Bo for that row the property foo's value with be nothing.

If that is what is happening then you can fix it by creating a BBS that is customized to your business object type. If you rthink this is where your problem is i can send you a copy of one I modified.

Paul

Greg:  I returned only a constant and the value still are not showing up in the grid.  Disturbing.  For some reason, as Paul is alluding to, the BBS is not picking up these values and passing them to the grid.

Guys...thanks for all of the help.  I am hitting the 24 hour mark on this current problem.  Hopefully, it will get resolved soon. 

Btw, I have eliminated any column adding and filtering options...I need to get the data flowing first to the grid.  I will go from there once that is back in business.

You may be dealing with post and information overload, but this is not an overly complicated process or problem...when I run into something like this it is generally due to frustration and dealing with the same problem over a period of time.  There is a lot of good information in this thread...but first things first, I had posted explaining how to ensure the column always exists within the CurrentDataTable.  Secondly, I have told you the one and only reason why a custom property would not be visible through the BBS.  Please check and refer to these two points and I am sure that you will see where your problem is.

The three columns (which are blank) are dragged from the available columns in the BBS to the layout of the grid.  All three are read-only custom properties that return a constant (3, 2, 1, respectively; no complex logic, at all, per Greg).   I have done nothing else.

You can see from my attached code earlier that I indeed have the proper ReflectionPropertyDescriptors set for each custom property.  Otherwise, these properties wouldn't even be seen by the grid design tool via the BBS.

I'll re-re-re-read everything, Trent.  I am not ignoring anyone's counsel.  I have acted on every part.

(I haven't found any towels, yet)
Bill

Were you able to review the code that I posted?  Other than the initialize and refilled code, I didn't think I was that far off.  Maybe I am.

At this point, I am just wanting a simple value to show up in the grid from a custom property.  Not even worried about filtering for now.

I am focusing on the BBS, as mentioned in an earlier post (following Greg's suggestion to return a constant).  My biggest issue is why the code works for one grid and not another.  Both have BOs with custom properties flowing through a BBS to the grid.

I'll continue to grind it out on my own.  Apparently, I have worn y'all out with this one. 

Sorry about that,
Bill

Don't even know wether this would make a difference or not, but had a look at your code and couldn't see the "OnSalesOrder" property defined (which you create a Descriptor for)... I guess you just didn't post it, is that so?

1)  Added code to the CurrentDataTableInitialized and CurrentDataTableRefilled (per Trent and Ivan)

3)  Filled the BO that applies a similar filter to what I wanted in the BO (removed that part of the problem entirely)

4)  Set all new data column values to the existing value of the custom property (note: using the various code supplied in this thread, the best I could do was fill the first row with data from the custom properties...the rows' column data mostly stayed empty)

5)  Create a dataset from the CurrentDataTable(s) to be the data source for the DevEx Grid (necessary for the master/detail gridviews, BBS bypassed)

There are a couple of outstanding issues...the main one is that once I set a column's value in the CurrentDataTable the row is now dirty and the BO wants to save whenever I exit the window.  I will do some searching on how to prevent saves in this situation.  I am sure it has been covered in the docs or other forum entries.  The secondary one is that the lookup data in the related sales order grid (e.g. customer name, unit description, etc.) is always empty.  Since this is new water for me, I will do my due diligence and research the DevEx grid more throroughly and come up with a solution.

Thanks, again, for everyone's help!  Naturally, if anyone sees something that may help me improve things, feel free to let me know.

Have a great day!
Bill

Not sure this is the recommended way, I'm sure you will be adviced against it if not. Have you tryed issuing a SAVE right after you modifiy all your custom field values? This is what I'm doing, anyway!

As this column is not part of your table, nothing will happen to it, I suppose.