Changing the behaviour of TextBox cells in DB Grid

[Jeck]

Hello,

I''m trying to code the following functionality:
Certain cells in the databound grid should contain editable values that are representations of some other values in the datasource.

Example:
column 1 should contain value of type "weight". While on the screen it would be displayed and edited as kgs, pounds, ounces etc; in datasource I want it to stay in kgs all the time.
column 2 has "linear dimension", that should be displayed/edited in meters, feet, yards, depending on configuration, but again, datasource should store it all in meters.

We already have a library of parsers/converters/validators that make it simple to convert any text value with specified units to standard units, and vice versa.

What I''m trying to figure out is where do I plug in these parsers and formatters?

Creating a new GridMyTextBoxCellModel with a new CellRendered seems like overkill - it''s still just a TextBox!..
Or can I inherit from GridTextBoxCellModel without creating my own renderer?

Thanks in advance!

[Administrator]

You can use the event, QueryCellFormattedText, to set the formatted value in a cell, say converting kgs to lbs. Then you could use SaveCellFormattedText to convert the value back. Here is a little sample that has values stored in kgs in column 1. The grid will display it in either kgs or lbs depending upon whether there is a # in column 2. KGStoLBS_1578.zip

[Michael Feinstein]

This seem like perfect solution, except we need a way to determine format information from QueryCellFormattedText parameters alone (the example uses another column).
I was thinking to inherit ColumnDescriptor (since we want to configure it anyway), is there a way to get to ColumnDescriptor class of the cell from GridCellTextEventArgs ?
Is it good way to go, or can you recommend another way? For example in DataBound grids one can override PropertyDescriptor.

[Administrator]

I am not sure what you mean by column descriptor.

If you mean GridBoundColumn or PropertyDescriptor, you can get those with code like:

int field = this.gridDataBoundGrid1.Binder.ColIndexToField(e.Style.CellIdentity.ColIndex);
GridBoundColumn gbc = this.gridDataBoundGrid1.Binder.InternalColumns[field];
PropertyDescriptor pd = gbc.PropertyDescriptor;

If you have explicitly added GridBoundColumns, then you would use the grid.GridBoundColumns collection in the above code instead of the InternalColumns collection.

If you mean something else, could you explain a little more about it.

[Michael Feinstein]

Sorry I was not very clear, we are going to use GroupingGrid, and there is plenty of information in ColumnDescriptor classes (that are in TableDescriptor) to allow us to dtermine in run-time on how to format text. What we need is a way to get to the information in the events (because ControlGrid has these 2 events as well)

>I am not sure what you mean by column descriptor.
>
>If you mean GridBoundColumn or PropertyDescriptor, you can get those with code like:
>

>int field = this.gridDataBoundGrid1.Binder.ColIndexToField(e.Style.CellIdentity.ColIndex);
>GridBoundColumn gbc = this.gridDataBoundGrid1.Binder.InternalColumns[field];
>PropertyDescriptor pd = gbc.PropertyDescriptor;
>

>
>If you have explicitly added GridBoundColumns, then you would use the grid.GridBoundColumns collection in the above code instead of the InternalColumns collection.
>
>If you mean something else, could you explain a little more about it.
>

[Administrator]

Here is some code that gets at the Record for the row from within the QueryCellFormattedText event on the main TableModel.

private void TableModel_QueryCellFormattedText(object sender, GridCellTextEventArgs e)
{
	Element el = this.groupingGrid1.Table.DisplayElements[e.Style.CellIdentity.RowIndex];
	RecordRow rec =  el as RecordRow ;
	if(rec != null)
	{
		Record r = rec.ParentRecord;
		DataRowView drv =  r.GetData() as DataRowView;
		if(drv != null)
		{
			Console.WriteLine("************ " + drv[0].ToString() + "  " + drv[1].ToString());
		}
	}
}