DataGrid row content vertical alignment

To set individual text alignments you can use:

<DataGridTextColumn.ElementStyle>
   <Style TargetType="TextBlock">
       <Setter Property="TextAlignment" Value="Center" />
   </Style>
</DataGridTextColumn.ElementStyle>

The following code will vertically align the content of a DataGridTextColumn cell:

<DataGridTextColumn.ElementStyle>
    <Style TargetType="TextBlock">
        <Setter Property="VerticalAlignment" Value="Center"></Setter>
    </Style>
</DataGridTextColumn.ElementStyle>

Edit: I've come back to this problem and found the solution below to work better, it will center the contents of all the cells in DataGridTextRows both horizontally and vertically.

<UserControl.Resources>    
    <ResourceDictionary>
        <Style TargetType="DataGridCell">
            <Setter Property="HorizontalAlignment" Value="Stretch"></Setter>
            <Setter Property="VerticalAlignment" Value="Stretch"></Setter>
            <Setter Property="VerticalContentAlignment" Value="Stretch"></Setter>
            <Setter Property="TextBlock.TextAlignment" Value="Center"></Setter>
            <Setter Property="TextBlock.VerticalAlignment" Value="Center"></Setter>
        </Style>    
    </ResourceDictionary>
</UserControl.Resources>

Complete solution of this issue at MSDN: Vertical alignment of DataGrid row content.

In brief, in style-file set:

<!--body content datagrid cell vertical centering-->
<Style x:Key="Body_Content_DataGrid_Centering"
        TargetType="{x:Type DataGridCell}">
    <Setter Property="Template">
        <Setter.Value>
            <ControlTemplate TargetType="{x:Type DataGridCell}">
                <Grid Background="{TemplateBinding Background}">
                    <ContentPresenter VerticalAlignment="Center" />
                </Grid>
            </ControlTemplate>
        </Setter.Value>
    </Setter>
</Style>

In window file:

<DataGrid x:Name="ContentDataGrid"
        Style="{StaticResource ContentDataGrid}"
        CellStyle="{StaticResource Body_Content_DataGrid_Centering}"
        ItemsSource="{Binding}"
        RowEditEnding="ContentDataGrid_RowEditEnding">
    <DataGrid.Columns>
        <DataGridTextColumn Header="UserID"
                Width="100"
                IsReadOnly="True"
                Binding="{Binding Path=userID}" />
        <DataGridTextColumn Header="UserName"
                Width="100"
                Binding="{Binding Path=userName}" />
        <DataGridTextColumn Header="UserAccessLevel"
                Width="100"
                Binding="{Binding Path=userAccessLevel}" />
        <DataGridTextColumn Header="UserPassword"
                Width="*"
                Binding="{Binding Path=userPassword}" />
    </DataGrid.Columns>
</DataGrid>

This will give you a wanted result: