Null dates - DateFormatString

[Chris]

Is there a way to set up the grid to display a blank cell for null dates.  Since my grid is bound to an observablecollection and the date is a DateTime (hence a null date become 01/01/0001), using DataFormatString="{}{0:d}" gives me the date as 01/01/0001. 

I would like this field to be blank. 

Thanks in advance

Chris

[Pavel Pavlov]

Hello Chris,

The sample project attached demonstrates how to achieve this using a custom value converter.
In the binding of the column we specify our converter. Then in the Convert method we check if the date is "null ". There is the place where you can do your custom formatting as well as I am not sure the column format string will still  work with this approach.

Best wishes,
Pavel Pavlov
the Telerik team

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[Chris]

Many thanks for the reply Pavel.

[Alfa]

Hi,

I implement the solution in Q3 2009 release.

Everything works fine but now it is not letting me go out of cell without entering a valid date.

It is showing "Input is not in correct format" error message when i try to leave it blank.

Any fix?

Rgds

Alfa

[Alfa]

I got the fix.

Stupid mistake of not converting null value in in DateTimeFormat in ConvertBack method was the issue.

Rdgs

Alfa

[Bill Jindrich]

Hi All,
I downloaded the sample ZIPped project and I see it working as desired. My problem is that my data is coming from a list of loaded objects that contain a number of properties (and my grid has a number of columns, each displaying a property). I can't figure out the syntax to use in either the .XAML or the .XAML.VB file in my project to associate the DateConverter with the date column. Here's a snippet of my current .XAML:
...

 

 

<telerikGridView:RadGridView.Columns>

 

<telerikGridView:GridViewDataColumn DataMemberBinding="{Binding origin}" Header="" />

 

 

 

<telerikGridView:GridViewDataColumn DataMemberBinding="{Binding title}" Header="Title" TextWrapping="Wrap" />

 

 

 

<telerikGridView:GridViewDataColumn DataMemberBinding="{Binding dueDate}" Header="Due Date" DataFormatString="{}{0:dd/MM/yyyy}" TextWrapping="Wrap" />

 

 

 

 

<telerikGridView:GridViewDataColumn DataMemberBinding="{Binding delivery}" Header="Delivery" TextWrapping="Wrap"/>

 

 

 

 

<telerikGridView:GridViewDataColumn DataMemberBinding="{Binding duration}" Header="Duration" TextWrapping="Wrap"/>

 

 

 

 

 

 

...

When I look in the sample project, I see:
 ...
<telerik:RadGridView.Columns>

 

 

 

 

 

 

<telerik:GridViewDataColumn DataMemberBinding="{Binding Converter={StaticResource MyDateConverter}}" HeaderText="Date" />

 

 

 

 

</telerik:RadGridView.Columns>
...
My challenge: what is the syntax that allows my to associate the DateConverter class, as above, with my date column that is bound to the dueDate property, keeping the dueDate property associated with the column, as well.

thanks in advance!

 

 

 

 

 

 

[Vlad]

Hi,

Here is an example:

<telerik:GridViewDataColumn DataMemberBinding="{Binding dueDate, Converter={StaticResource MyDateConverter}}"  />

Sincerely yours,
Vlad
the Telerik team

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[danparker276]

The converter won't work with the aggregate function though right?  There's no easy way around this.


                        <telerik:GridViewDataColumn.AggregateFunctions>
                            <telerik:MinFunction ResultFormatString="{}First: {0:d}" SourceField="Date" />
                            <telerik:MaxFunction ResultFormatString="{}Last: {0:d}" SourceField="Date" />
                        </telerik:GridViewDataColumn.AggregateFunctions>

[Vlad]

Hi,

You can apply converter to the Binding in your custom footer/group footer. Please check this demo for more info how to define custom footers. 

All the best,
Vlad
the Telerik team

[Marcel]

This also helped - from http://www.telerik.com/community/forums/silverlight/gridview/converter-staticresource-myconverter-in-c.aspx

<Grid.Resources>

  <local:MyConverter x:Key="myDataConverter" />

</Grid.Resources>

 

<telerik:GridViewDataColumn Header="Discontinued" DataMemberBinding="{Binding Discontinued}">
<telerik:GridViewDataColumn.CellTemplate>
 <DataTemplate>
    <TextBlock Text="{Binding Discontinued, Converter={StaticResource myConverter}}" />
</DataTemplate>
</telerik:GridViewDataColumn.CellTemplate>

</telerik:GridViewDataColumn>