DisplayMemberPath concatenation

unairoldan picture unairoldan · Apr 17, 2012 · Viewed 24.8k times · Source

I am trying to bind two values to a ComboBox display value, but I do not know how to do.

This way does not work:

cboRegion.DisplayMemberPath = "idregion" + "description";

Does anyone know how to do that in C#?

Answer

Heinzi picture Heinzi · Apr 17, 2012

Unfortunately, this is not possible with DisplayMemberPath. You have the following alternatives:

  • Specify a DataTemplate

    <ComboBox>
      <ComboBox.ItemTemplate>
        <DataTemplate>
          <TextBlock>
            <TextBlock.Text>
              <MultiBinding StringFormat="{}{0}: {1}">
                <Binding Path="idregion"/>
                <Binding Path="description"/>
              </MultiBinding>
            </TextBlock.Text>
          </TextBlock>
        </DataTemplate>
      </ComboBox.ItemTemplate>
    </ComboBox>
    

    (If you are wondering about the empty braces in the StringFormat attribute, see: What do the {} brackets mean in the StringFormat section of a Binding syntax?)

  • Add a property or field to your data source. How to do that depends on your data source:

    If your combo box is bound to a DataTable, add a DataColumn and fill its values in a loop. Alternatively, change your SQL and add the concatenated value to your SELECT clause.

    If your combo box is bound to a POCO or entity framework object, add a property that returns the concatenation.