How to show part of text in datagrid row details? - wpfdatagrid

Question

I have table in my database which has fields of ID,NAME,CONTEXT. I am showing search result in datagrid. Now I tried to do this
<WpfToolkit:DataGrid.RowDetailsTemplate>
<DataTemplate>
**<StackPanel Orientation="Horizontal" Margin="5">
<StackPanel Orientation="Vertical" Margin="5">
<TextBlock Foreground="CadetBlue" FontSize="13"
Width="Auto" TextWrapping="Wrap"
Text="{Binding Path=Context}"/>
</StackPanel>**
</StackPanel>
</DataTemplate>
</WpfToolkit:DataGrid.RowDetailsTemplate>
It is giving whole text which is not what I want. If you give me some directions how to do this, may be some code. It will be appreciated. I want to show only that part of text which is selected by this line of code.
private void Find_Click(object sender, RoutedEventArgs e)
{
DataSet ds = new DataSet();
cmdSel = new SqlCommand();
cmdSel.Connection = MainWindow.conn;
cmdSel.CommandText = "select id,Name,Context from document where Contains([Context],'FormsOf (INFLECTIONAL, \"" + TextBoxSearch.Text + "\")')";
da = new SqlDataAdapter(cmdSel);
da.Fill(ds, "MainSearchBinding");
resWin.DataGrid1.DataContext = ds;
}
For example you are searching for "audio" and it is showing 10 words before + "audio" + 10 word after audio. Thank in advance.

Answer 1

I add one more column "Intro" to my table.
<WpfToolkit:DataGrid.RowDetailsTemplate>
<DataTemplate>
<StackPanel Orientation="Horizontal" Margin="5">
<StackPanel Orientation="Vertical" Margin="5" >
<TextBlock Foreground="CadetBlue" FontSize="13"
Width="Auto" TextWrapping="Wrap"
Text="{Binding Path=Intro}"/>
</StackPanel>
</StackPanel>
</DataTemplate>
</WpfToolkit:DataGrid.RowDetailsTemplate>
And wrote this code for mouse click.
private void OnMouseClick(object sender, MouseButtonEventArgs e)
{
IList rows = DataGrid1.SelectedItems;
DataRowView row = (DataRowView)DataGrid1.SelectedItems[0];
int a = (int)row["ID"];
string t = (string)row["Context"]; //getting all text from Context
string srch1 = UCSearch.srch; // search box text
if (t.IndexOf(srch1) != -1)
{
string retString = t.Substring(t.IndexOf(srch1), 100); //cutting from occured text and more 100 symbols
row["Intro"] = retString; // setting to Intro Column
}
}
I hope some one may need it. Thank you.