How to specify the width of the datagrid column to occupy the remaining space?
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I am developing silverlight 4 Application. I have the following datagrid

 

    <data:DataGrid x:Name="StudentDataGrid" AutoGenerateColumns="False" Height="200" HorizontalAlignment="Left" Margin="176,96,0,0" VerticalAlignment="Top" Width="200">
                <data:DataGrid.Columns>
                    <data:DataGridTextColumn Header="First Name" Binding="{Binding FirstName}"></data:DataGridTextColumn>
                    <data:DataGridTextColumn Width="*" Header="Last Name" Binding="{Binding LastName}" ></data:DataGridTextColumn>
                    
                </data:DataGrid.Columns>
            </data:DataGrid>


I am binding the following list to this datagrid

     public List<Student> GetStudents()
            {
                List<Student> studentList = new List<Student>();
                Student s1 = new Student();
                s1.FirstName = "Anil";
                s1.LastName = "Jadhav";
                Student s2 = new Student();
                s2.FirstName = "Shyam";
                s2.LastName = "Jodh";
                studentList.Add(s1);
                studentList.Add(s2);
                return studentList;
            }


The code works fine. The * width occupy the remaining space. But wen the s1.FirstName is assigned value which has very long string then the the code run but the datagrid does not show the scrollbar. The LastName column goes to the right side and it gets hidden. I dont want to increase the width of the datagrd. How to solve the above problem ? Why datagrid not showing the scrollbar ? Can you please provide me any code or link through which I can solve the above issue.