How to do DataGrid Column sort from code behind?

Question

I have a DataGrid in my project where I am hiding the column headers. When user clicks on a button, I want to sort grid based on first column.

I tried following code which is not working

public MainWindow()
 {
     InitializeComponent();
     dataGrid1.Loaded += (s, e) =>
     {
        dataGrid1.Sorting -= DataGrid1_Sorting;
        dataGrid1.Sorting += DataGrid1_Sorting;
     };
  }

  private void DataGrid1_Sorting(object sender, DataGridSortingEventArgs e)
  {
  }

  private void Button_Click(object sender, RoutedEventArgs e)
  {
     DataGrid1_Sorting(dataGrid1, new DataGridSortingEventArgs(dataGrid1.Columns[0]));
  }

But when I dont hide mu column header and click on it, it sorts column. Please help.