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DataGridView.ColumnHeaderMouseClick Event

Definition

Occurs when the user clicks a column header.

public:
 event System::Windows::Forms::DataGridViewCellMouseEventHandler ^ ColumnHeaderMouseClick;
public event System.Windows.Forms.DataGridViewCellMouseEventHandler ColumnHeaderMouseClick;
public event System.Windows.Forms.DataGridViewCellMouseEventHandler? ColumnHeaderMouseClick;
member this.ColumnHeaderMouseClick : System.Windows.Forms.DataGridViewCellMouseEventHandler 
Public Custom Event ColumnHeaderMouseClick As DataGridViewCellMouseEventHandler 

Event Type

Examples

When a column heading is clicked in a DataGridView, the default behavior is to order the grid rows based on the clicked column, or to reverse the sort order if the grid is already sorted by the clicked column. The following code example demonstrates how to use this event to perform a programmatic sort that emulates the default behavior of clicking a DataGridViewColumnHeaderCell when the default behavior has been disabled. In this example, the SelectionMode is set to ColumnHeaderSelect, so clicking the DataGridViewColumnHeaderCell selects the contents of the column. For the example code to function as intended, the default column header click behavior needs to be changed each time the data is loaded into the DataGridView. Add a DataBindingComplete event handler to provide the code that changes the default behavior. To run this example, paste the code into a form that contains a DataGridView named dataGridView1 and ensure that all events are associated with their event handlers.

private void dataGridView1_ColumnHeaderMouseClick(
    object sender, DataGridViewCellMouseEventArgs e)
{
    DataGridViewColumn newColumn = dataGridView1.Columns[e.ColumnIndex];
    DataGridViewColumn oldColumn = dataGridView1.SortedColumn;
    ListSortDirection direction;

    // If oldColumn is null, then the DataGridView is not sorted.
    if (oldColumn != null)
    {
        // Sort the same column again, reversing the SortOrder.
        if (oldColumn == newColumn &&
            dataGridView1.SortOrder == SortOrder.Ascending)
        {
            direction = ListSortDirection.Descending;
        }
        else
        {
            // Sort a new column and remove the old SortGlyph.
            direction = ListSortDirection.Ascending;
            oldColumn.HeaderCell.SortGlyphDirection = SortOrder.None;
        }
    }
    else
    {
        direction = ListSortDirection.Ascending;
    }

    // Sort the selected column.
    dataGridView1.Sort(newColumn, direction);
    newColumn.HeaderCell.SortGlyphDirection =
        direction == ListSortDirection.Ascending ?
        SortOrder.Ascending : SortOrder.Descending;
}

private void dataGridView1_DataBindingComplete(object sender,
    DataGridViewBindingCompleteEventArgs e)
{
    // Put each of the columns into programmatic sort mode.
    foreach (DataGridViewColumn column in dataGridView1.Columns)
    {
        column.SortMode = DataGridViewColumnSortMode.Programmatic;
    }
}
Private Sub dataGridView1_ColumnHeaderMouseClick(ByVal sender As Object, _
    ByVal e As DataGridViewCellMouseEventArgs) _
    Handles dataGridView1.ColumnHeaderMouseClick

    Dim newColumn As DataGridViewColumn = _
        dataGridView1.Columns(e.ColumnIndex)
    Dim oldColumn As DataGridViewColumn = dataGridView1.SortedColumn
    Dim direction As ListSortDirection

    ' If oldColumn is null, then the DataGridView is not currently sorted.
    If oldColumn IsNot Nothing Then

        ' Sort the same column again, reversing the SortOrder.
        If oldColumn Is newColumn AndAlso dataGridView1.SortOrder = _
            SortOrder.Ascending Then
            direction = ListSortDirection.Descending
        Else

            ' Sort a new column and remove the old SortGlyph.
            direction = ListSortDirection.Ascending
            oldColumn.HeaderCell.SortGlyphDirection = SortOrder.None
        End If
    Else
        direction = ListSortDirection.Ascending
    End If

    ' Sort the selected column.
    dataGridView1.Sort(newColumn, direction)
    If direction = ListSortDirection.Ascending Then
        newColumn.HeaderCell.SortGlyphDirection = SortOrder.Ascending
    Else
        newColumn.HeaderCell.SortGlyphDirection = SortOrder.Descending
    End If

End Sub

Private Sub dataGridView1_DataBindingComplete(ByVal sender As Object, _
    ByVal e As DataGridViewBindingCompleteEventArgs) _
    Handles dataGridView1.DataBindingComplete

    ' Put each of the columns into programmatic sort mode.
    For Each column As DataGridViewColumn In dataGridView1.Columns
        column.SortMode = DataGridViewColumnSortMode.Programmatic
    Next
End Sub

Remarks

For more information about how to handle events, see Handling and Raising Events.

Applies to

See also