DataGridViewCellMouseEventArgs.ColumnIndex Property        
Definition
Important
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Gets the zero-based column index of the cell.
public:
 property int ColumnIndex { int get(); };
	public int ColumnIndex { get; }
	member this.ColumnIndex : int
	Public ReadOnly Property ColumnIndex As Integer
	Property Value
An integer specifying the column index.
Examples
The following code example illustrates the use of this property.
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