在DataGridComboBoxColumn中编辑单元格时如何获取“当前单元格”值？

Question

I am new to WPF, trying to fix up an autosuggest DataGridComboBoxColumn

<DataGridComboBoxColumn x:Name="list_itemname" Width="*" Header="Item Name"  >
    <DataGridComboBoxColumn.EditingElementStyle>
        <Style TargetType="ComboBox">
            <Setter Property="IsEditable" Value="True"/>
            <Setter Property="ItemsSource" Value="{Binding Path=itemlist}" />
        </Style>
    </DataGridComboBoxColumn.EditingElementStyle>
</DataGridComboBoxColumn>

Answer 1

You have to catch event related to changing the cell: CellEditEnding. First you have to declare method that will handle the event:

void cellEditEnding(object sender, DataGridCellEditEndingEventArgs e)
{
    var editedComboBoxColumn = e.EditingElement as ComboBox;
}

and then hook up handler with your grid:

<DataGrid x:Name="grid" CellEditEnding="cellEditEnding" />

Answer 2

Instead of using a datagrid combobox column, I recommend you use a datagrid template column.

Roughly

    <DataGridTemplateColumn>
        <DataGridTemplateColumn.CellTemplate>
            <DataTemplate>
                <ComboBox IsEditable="True" 
                          Text="{Binding PropertyInRow}" 
                          ItemsSource="{Binding itemlist}"/>
            </DataTemplate>
        </DataGridTemplateColumn.CellTemplate>

Here PropertyInRow is the name of a propfull in a row viewmodel. Whatever your itemssource of the datagrid is bound to being an observablecollection.

If you want to do something when the text changes then you can put code in the setter of that propfull.

This is the mvvm pattern and you should learn that from the start if you plan on doing any serious wpf development. Certainly if you plan on working in a commercial wpf team because they all use mvvm.

Also.

If itemlist is not a property in the rowviewmodel and instead is somewhere in the window viewmodel then you'll want some relativesource on that binding.

Answer 3

If your ItemSource is a ListCollectView, you can get the current item like this:

public void OnCellValueChanged(object sender, CellValueChangedEventArgs e)
{
    var currentItem = itemlist.CurrentItem; // to get the whole current item

    // Or you just get the current changed cell value from the EventArgs:
    var currentValue = e.Value?.ToString();
}