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Sort Method (IComparer)
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DataGridView.Sort Method (IComparer)

Sorts the contents of the DataGridView control using an implementation of the IComparer interface.

Namespace:  System.Windows.Forms
Assembly:  System.Windows.Forms (in System.Windows.Forms.dll)

Public Overridable Sub Sort ( _
	comparer As IComparer _


Type: System.Collections.IComparer

An implementation of IComparer that performs the custom sorting operation.


comparer is Nothing.


VirtualMode is set to true.


DataSource is not Nothing.

This method allows advanced customization of the sorting feature of the DataGridView class. In order to implement a highly customized sorting operation, you can write an event handler for the ColumnHeaderMouseClick event and call this method with an instance of a class that implements the System.Collections.IComparer interface as a parameter. In this case, you will typically set the DataGridViewColumn.SortMode property to DataGridViewColumnSortMode.Programmatic to disable automatic sorting and to leave room for a sorting glyph. When sorting by columns set to programmatic sort mode, you must display the sorting glyph yourself by setting the DataGridViewColumnHeaderCell.SortGlyphDirection property.

This method works only when the DataSource property is not set. When you bind the DataGridView control to an external data source, you must use the sorting operations provided by that data source. When you provide your own data source by implementing virtual mode, you must also handle the sorting operations yourself.

Calling this method automatically sets the CurrentCell property to Nothing.

The following code example demonstrates how to use the Sort method overload in a multiple column sort scenario. In this example, the IComparer interface is implemented in the RowComparer class.

Private Sub Button1_Click(ByVal sender As Object, ByVal e As EventArgs) _
Handles Button1.Click
    If RadioButton1.Checked = True Then
        DataGridView1.Sort(New RowComparer(SortOrder.Ascending))
    ElseIf RadioButton2.Checked = True Then
        DataGridView1.Sort(New RowComparer(SortOrder.Descending))
    End If 
End Sub 

Private Class RowComparer
    Implements System.Collections.IComparer

    Private sortOrderModifier As Integer = 1

    Public Sub New(ByVal sortOrder As SortOrder)
        If sortOrder = sortOrder.Descending Then
            sortOrderModifier = -1
        ElseIf sortOrder = sortOrder.Ascending Then

            sortOrderModifier = 1
        End If 
    End Sub 

    Public Function Compare(ByVal x As Object, ByVal y As Object) As Integer _
        Implements System.Collections.IComparer.Compare

        Dim DataGridViewRow1 As DataGridViewRow = CType(x, DataGridViewRow)
        Dim DataGridViewRow2 As DataGridViewRow = CType(y, DataGridViewRow)

        ' Try to sort based on the Last Name column. 
        Dim CompareResult As Integer = System.String.Compare( _
            DataGridViewRow1.Cells(1).Value.ToString(), _

        ' If the Last Names are equal, sort based on the First Name. 
        If CompareResult = 0 Then
            CompareResult = System.String.Compare( _
                DataGridViewRow1.Cells(0).Value.ToString(), _
        End If 
        Return CompareResult * sortOrderModifier
    End Function 
End Class

.NET Framework

Supported in: 4.6, 4.5, 4, 3.5, 3.0, 2.0

.NET Framework Client Profile

Supported in: 4, 3.5 SP1
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