DataGridColumnStyle Classe

Definição

public ref class DataGridColumnStyle abstract : System::ComponentModel::Component, System::Windows::Forms::IDataGridColumnStyleEditingNotificationService

public abstract class DataGridColumnStyle : System.ComponentModel.Component, System.Windows.Forms.IDataGridColumnStyleEditingNotificationService

type DataGridColumnStyle = class
    inherit Component
    interface IDataGridColumnStyleEditingNotificationService

Public MustInherit Class DataGridColumnStyle
Inherits Component
Implements IDataGridColumnStyleEditingNotificationService

Herança

Object

MarshalByRefObject

Component

DataGridColumnStyle

Derivado

System.Windows.Forms.DataGridBoolColumn

System.Windows.Forms.DataGridTextBoxColumn

Implementações

IDataGridColumnStyleEditingNotificationService

Exemplos

O exemplo de código a seguir cria um DataGridColumnStyle que hospeda um DateTimePicker controle .

#using <System.dll>
#using <System.Data.dll>
#using <System.Drawing.dll>
#using <System.Windows.Forms.dll>
#using <System.Xml.dll>

using namespace System;
using namespace System::Data;
using namespace System::Windows::Forms;
using namespace System::Drawing;
using namespace System::Security::Permissions;

// This example shows how to create your own column style that
// hosts a control, in this case, a DateTimePicker.

public ref class CustomDateTimePicker : public DateTimePicker
{
protected:
    [SecurityPermission(SecurityAction::Demand, Flags=SecurityPermissionFlag::UnmanagedCode)]
    virtual bool ProcessKeyMessage( Message% m ) override
    {
        // Keep all the keys for the DateTimePicker.
        return ProcessKeyEventArgs( m );
    }
};

public ref class DataGridTimePickerColumn : public DataGridColumnStyle
{
private:
   CustomDateTimePicker^ customDateTimePicker1;

   // The isEditing field tracks whether or not the user is
   // editing data with the hosted control.
   bool isEditing;

public:
   DataGridTimePickerColumn()
   {
      customDateTimePicker1 = gcnew CustomDateTimePicker;
      customDateTimePicker1->Visible = false;
   }

protected:
   virtual void Abort( int /*rowNum*/ ) override
   {
      isEditing = false;
      customDateTimePicker1->ValueChanged -=
         gcnew EventHandler( this, &DataGridTimePickerColumn::TimePickerValueChanged );
      Invalidate();
   }

   virtual bool Commit( CurrencyManager^ dataSource, int rowNum ) override
   {
      customDateTimePicker1->Bounds = Rectangle::Empty;

      customDateTimePicker1->ValueChanged -=
         gcnew EventHandler( this, &DataGridTimePickerColumn::TimePickerValueChanged );
      
      if (  !isEditing )
         return true;

      isEditing = false;

      try
      {
         DateTime value = customDateTimePicker1->Value;
         SetColumnValueAtRow( dataSource, rowNum, value );
      }
      catch ( Exception^ ) 
      {
         Abort( rowNum );
         return false;
      }

      Invalidate();
      return true;
   }

   virtual void Edit(
      CurrencyManager^ source,
      int rowNum,
      Rectangle bounds,
      bool /*readOnly*/,
      String^ /*displayText*/,
      bool cellIsVisible ) override
   {
      DateTime value =  (DateTime)
         GetColumnValueAtRow( source, rowNum );
      if ( cellIsVisible )
      {
         customDateTimePicker1->Bounds = Rectangle(
            bounds.X + 2, bounds.Y + 2,
            bounds.Width - 4, bounds.Height - 4 );
         customDateTimePicker1->Value = value;
         customDateTimePicker1->Visible = true;
         customDateTimePicker1->ValueChanged +=
            gcnew EventHandler( this, &DataGridTimePickerColumn::TimePickerValueChanged );
      }
      else
      {
         customDateTimePicker1->Value = value;
         customDateTimePicker1->Visible = false;
      }

      if ( customDateTimePicker1->Visible )
         DataGridTableStyle->DataGrid->Invalidate( bounds );

      customDateTimePicker1->Focus();
   }

   virtual System::Drawing::Size GetPreferredSize(
      Graphics^ /*g*/,
      Object^ /*value*/ ) override
   {
      return Size( 100, customDateTimePicker1->PreferredHeight + 4);
   }

   virtual int GetMinimumHeight() override
   {
      return customDateTimePicker1->PreferredHeight + 4;
   }

   virtual int GetPreferredHeight( Graphics^ /*g*/,
      Object^ /*value*/ ) override
   {
      return customDateTimePicker1->PreferredHeight + 4;
   }

   virtual void Paint( Graphics^ g,
      Rectangle bounds,
      CurrencyManager^ source,
      int rowNum ) override
   {
      Paint( g, bounds, source, rowNum, false );
   }

   virtual void Paint(
      Graphics^ g,
      Rectangle bounds,
      CurrencyManager^ source,
      int rowNum,
      bool alignToRight ) override
   {
      Paint(
         g, bounds,
         source,
         rowNum,
         Brushes::Red,
         Brushes::Blue,
         alignToRight );
   }

   virtual void Paint(
      Graphics^ g,
      Rectangle bounds,
      CurrencyManager^ source,
      int rowNum,
      Brush^ backBrush,
      Brush^ foreBrush,
      bool /*alignToRight*/ ) override
   {
      DateTime date =  (DateTime)
         GetColumnValueAtRow( source, rowNum );
      Rectangle rect = bounds;
      g->FillRectangle( backBrush, rect );
      rect.Offset( 0, 2 );
      rect.Height -= 2;
      g->DrawString( date.ToString( "d" ),
         this->DataGridTableStyle->DataGrid->Font,
         foreBrush, rect );
   }

   virtual void SetDataGridInColumn( DataGrid^ value ) override
   {
      DataGridColumnStyle::SetDataGridInColumn( value );
      if ( customDateTimePicker1->Parent != nullptr )
      {
         customDateTimePicker1->Parent->Controls->Remove
            ( customDateTimePicker1 );
      }
      if ( value != nullptr )
      {
         value->Controls->Add( customDateTimePicker1 );
      }
   }

private:
   void TimePickerValueChanged( Object^ /*sender*/, EventArgs^ /*e*/ )
   {
      // Remove the handler to prevent it from being called twice in a row.
      customDateTimePicker1->ValueChanged -=
         gcnew EventHandler( this, &DataGridTimePickerColumn::TimePickerValueChanged );
      this->isEditing = true;
      DataGridColumnStyle::ColumnStartedEditing( customDateTimePicker1 );
   }
};

public ref class MyForm: public Form
{
private:
   DataTable^ namesDataTable;
   DataGrid^ grid;
public:
   MyForm()
   {
      grid = gcnew DataGrid;

      InitForm();

      namesDataTable = gcnew DataTable( "NamesTable" );
      namesDataTable->Columns->Add( gcnew DataColumn( "Name" ) );
      DataColumn^ dateColumn = gcnew DataColumn
         ( "Date",DateTime::typeid );
      dateColumn->DefaultValue = DateTime::Today;
      namesDataTable->Columns->Add( dateColumn );
      DataSet^ namesDataSet = gcnew DataSet;
      namesDataSet->Tables->Add( namesDataTable );
      grid->DataSource = namesDataSet;
      grid->DataMember = "NamesTable";
      AddGridStyle();
      AddData();
   }

private:
   void AddGridStyle()
   {
      DataGridTableStyle^ myGridStyle = gcnew DataGridTableStyle;
      myGridStyle->MappingName = "NamesTable";
      DataGridTextBoxColumn^ nameColumnStyle =
         gcnew DataGridTextBoxColumn;
      nameColumnStyle->MappingName = "Name";
      nameColumnStyle->HeaderText = "Name";
      myGridStyle->GridColumnStyles->Add( nameColumnStyle );

      DataGridTimePickerColumn^ timePickerColumnStyle =
         gcnew DataGridTimePickerColumn;
      timePickerColumnStyle->MappingName = "Date";
      timePickerColumnStyle->HeaderText = "Date";
      timePickerColumnStyle->Width = 100;
      myGridStyle->GridColumnStyles->Add( timePickerColumnStyle );

      grid->TableStyles->Add( myGridStyle );
   }

   void AddData()
   {
      DataRow^ dRow = namesDataTable->NewRow();
      dRow->default[ "Name" ] = "Name 1";
      dRow->default[ "Date" ] = DateTime(2001,12,01);
      namesDataTable->Rows->Add( dRow );

      dRow = namesDataTable->NewRow();
      dRow->default[ "Name" ] = "Name 2";
      dRow->default[ "Date" ] = DateTime(2001,12,04);
      namesDataTable->Rows->Add( dRow );

      dRow = namesDataTable->NewRow();
      dRow->default[ "Name" ] = "Name 3";
      dRow->default[ "Date" ] = DateTime(2001,12,29);
      namesDataTable->Rows->Add( dRow );

      dRow = namesDataTable->NewRow();
      dRow->default[ "Name" ] = "Name 4";
      dRow->default[ "Date" ] = DateTime(2001,12,13);
      namesDataTable->Rows->Add( dRow );

      dRow = namesDataTable->NewRow();
      dRow->default[ "Name" ] = "Name 5";
      dRow->default[ "Date" ] = DateTime(2001,12,21);
      namesDataTable->Rows->Add( dRow );

      namesDataTable->AcceptChanges();
   }

   void InitForm()
   {
      this->Size = System::Drawing::Size( 500, 500 );
      grid->Size = System::Drawing::Size( 350, 250 );
      grid->TabStop = true;
      grid->TabIndex = 1;
      this->StartPosition = FormStartPosition::CenterScreen;
      this->Controls->Add( grid );
   }
};

[STAThread]
int main()
{
   Application::Run( gcnew MyForm );
}

using System;
using System.Data;
using System.Windows.Forms;
using System.Drawing;

// This example shows how to create your own column style that
// hosts a control, in this case, a DateTimePicker.
public class DataGridTimePickerColumn : DataGridColumnStyle
{
    private CustomDateTimePicker customDateTimePicker1 = 
        new CustomDateTimePicker();

    // The isEditing field tracks whether or not the user is
    // editing data with the hosted control.
    private bool isEditing;

    public DataGridTimePickerColumn() : base()
    {
        customDateTimePicker1.Visible = false;
    }

    protected override void Abort(int rowNum)
    {
        isEditing = false;
        customDateTimePicker1.ValueChanged -=
            new EventHandler(TimePickerValueChanged);
        Invalidate();
    }

    protected override bool Commit
        (CurrencyManager dataSource, int rowNum)
    {
        customDateTimePicker1.Bounds = Rectangle.Empty;

        customDateTimePicker1.ValueChanged -=
            new EventHandler(TimePickerValueChanged);

        if (!isEditing)
            return true;

        isEditing = false;

        try
        {
            DateTime value = customDateTimePicker1.Value;
            SetColumnValueAtRow(dataSource, rowNum, value);
        }
        catch (Exception)
        {
            Abort(rowNum);
            return false;
        }

        Invalidate();
        return true;
    }

    protected override void Edit(
        CurrencyManager source,
        int rowNum,
        Rectangle bounds,
        bool readOnly,
        string displayText,
        bool cellIsVisible)
    {
        DateTime value = (DateTime)
            GetColumnValueAtRow(source, rowNum);
        if (cellIsVisible)
        {
            customDateTimePicker1.Bounds = new Rectangle
                (bounds.X + 2, bounds.Y + 2,
                bounds.Width - 4, bounds.Height - 4);
            customDateTimePicker1.Value = value;
            customDateTimePicker1.Visible = true;
            customDateTimePicker1.ValueChanged +=
                new EventHandler(TimePickerValueChanged);
        }
        else
        {
            customDateTimePicker1.Value = value;
            customDateTimePicker1.Visible = false;
        }

        if (customDateTimePicker1.Visible)
            DataGridTableStyle.DataGrid.Invalidate(bounds);

        customDateTimePicker1.Focus();
    }

    protected override Size GetPreferredSize(
        Graphics g,
        object value)
    {
        return new Size(100, customDateTimePicker1.PreferredHeight + 4);
    }

    protected override int GetMinimumHeight()
    {
        return customDateTimePicker1.PreferredHeight + 4;
    }

    protected override int GetPreferredHeight(Graphics g,
        object value)
    {
        return customDateTimePicker1.PreferredHeight + 4;
    }

    protected override void Paint(Graphics g,
        Rectangle bounds,
        CurrencyManager source,
        int rowNum)
    {
        Paint(g, bounds, source, rowNum, false);
    }

    protected override void Paint(
        Graphics g,
        Rectangle bounds,
        CurrencyManager source,
        int rowNum,
        bool alignToRight)
    {
        Paint(
            g, bounds,
            source,
            rowNum,
            Brushes.Red,
            Brushes.Blue,
            alignToRight);
    }

    protected override void Paint(
        Graphics g,
        Rectangle bounds,
        CurrencyManager source,
        int rowNum,
        Brush backBrush,
        Brush foreBrush,
        bool alignToRight)
    {
        DateTime date = (DateTime)
            GetColumnValueAtRow(source, rowNum);
        Rectangle rect = bounds;
        g.FillRectangle(backBrush, rect);
        rect.Offset(0, 2);
        rect.Height -= 2;
        g.DrawString(date.ToString("d"),
            this.DataGridTableStyle.DataGrid.Font,
            foreBrush, rect);
    }

    protected override void SetDataGridInColumn(DataGrid value)
    {
        base.SetDataGridInColumn(value);
        if (customDateTimePicker1.Parent != null)
        {
            customDateTimePicker1.Parent.Controls.Remove
                (customDateTimePicker1);
        }
        if (value != null)
        {
            value.Controls.Add(customDateTimePicker1);
        }
    }

    private void TimePickerValueChanged(object sender, EventArgs e)
    {
        // Remove the handler to prevent it from being called twice in a row.
        customDateTimePicker1.ValueChanged -=
            new EventHandler(TimePickerValueChanged);
        this.isEditing = true;
        base.ColumnStartedEditing(customDateTimePicker1);
    }
}

public class CustomDateTimePicker : DateTimePicker
{
    protected override bool ProcessKeyMessage(ref Message m)
    {
        // Keep all the keys for the DateTimePicker.
        return ProcessKeyEventArgs(ref m);
    }
}

public class MyForm : Form
{
    private DataTable namesDataTable;
    private DataGrid grid = new DataGrid();
    public MyForm() : base()
    {
        InitForm();

        namesDataTable = new DataTable("NamesTable");
        namesDataTable.Columns.Add(new DataColumn("Name"));
        DataColumn dateColumn = new DataColumn
            ("Date", typeof(DateTime));
        dateColumn.DefaultValue = DateTime.Today;
        namesDataTable.Columns.Add(dateColumn);
        DataSet namesDataSet = new DataSet();
        namesDataSet.Tables.Add(namesDataTable);
        grid.DataSource = namesDataSet;
        grid.DataMember = "NamesTable";
        AddGridStyle();
        AddData();
    }

    private void AddGridStyle()
    {
        DataGridTableStyle myGridStyle = new DataGridTableStyle();
        myGridStyle.MappingName = "NamesTable";

        DataGridTextBoxColumn nameColumnStyle =
            new DataGridTextBoxColumn();
        nameColumnStyle.MappingName = "Name";
        nameColumnStyle.HeaderText = "Name";
        myGridStyle.GridColumnStyles.Add(nameColumnStyle);

        DataGridTimePickerColumn timePickerColumnStyle =
            new DataGridTimePickerColumn();
        timePickerColumnStyle.MappingName = "Date";
        timePickerColumnStyle.HeaderText = "Date";
        timePickerColumnStyle.Width = 100;
        myGridStyle.GridColumnStyles.Add(timePickerColumnStyle);

        grid.TableStyles.Add(myGridStyle);
    }

    private void AddData()
    {

        DataRow dRow = namesDataTable.NewRow();
        dRow["Name"] = "Name 1";
        dRow["Date"] = new DateTime(2001, 12, 01);
        namesDataTable.Rows.Add(dRow);

        dRow = namesDataTable.NewRow();
        dRow["Name"] = "Name 2";
        dRow["Date"] = new DateTime(2001, 12, 04);
        namesDataTable.Rows.Add(dRow);

        dRow = namesDataTable.NewRow();
        dRow["Name"] = "Name 3";
        dRow["Date"] = new DateTime(2001, 12, 29);
        namesDataTable.Rows.Add(dRow);

        dRow = namesDataTable.NewRow();
        dRow["Name"] = "Name 4";
        dRow["Date"] = new DateTime(2001, 12, 13);
        namesDataTable.Rows.Add(dRow);

        dRow = namesDataTable.NewRow();
        dRow["Name"] = "Name 5";
        dRow["Date"] = new DateTime(2001, 12, 21);
        namesDataTable.Rows.Add(dRow);

        namesDataTable.AcceptChanges();
    }

    private void InitForm()
    {
        this.Size = new Size(500, 500);
        grid.Size = new Size(350, 250);
        grid.TabStop = true;
        grid.TabIndex = 1;
        this.StartPosition = FormStartPosition.CenterScreen;
        this.Controls.Add(grid);
    }
 
    [STAThread]
    public static void Main()
    {
        Application.Run(new MyForm());
    }
}

Imports System.Data
Imports System.Windows.Forms
Imports System.Drawing
Imports System.ComponentModel
Imports System.Security.Permissions

' This example shows how to create your own column style that
' hosts a control, in this case, a DateTimePicker.
Public Class DataGridTimePickerColumn
    Inherits DataGridColumnStyle

    Private customDateTimePicker1 As New CustomDateTimePicker()

    ' The isEditing field tracks whether or not the user is
    ' editing data with the hosted control.
    Private isEditing As Boolean

    Public Sub New()
        customDateTimePicker1.Visible = False
    End Sub

    Protected Overrides Sub Abort(ByVal rowNum As Integer)
        isEditing = False
        RemoveHandler customDateTimePicker1.ValueChanged, _
            AddressOf TimePickerValueChanged
        Invalidate()
    End Sub

    Protected Overrides Function Commit _
        (ByVal dataSource As CurrencyManager, ByVal rowNum As Integer) _
        As Boolean

        customDateTimePicker1.Bounds = Rectangle.Empty

        RemoveHandler customDateTimePicker1.ValueChanged, _
            AddressOf TimePickerValueChanged

        If Not isEditing Then
            Return True
        End If
        isEditing = False

        Try
            Dim value As DateTime = customDateTimePicker1.Value
            SetColumnValueAtRow(dataSource, rowNum, value)
        Catch
        End Try

        Invalidate()
        Return True
    End Function

    Protected Overloads Overrides Sub Edit( _
        ByVal [source] As CurrencyManager, _
        ByVal rowNum As Integer, _
        ByVal bounds As Rectangle, _
        ByVal [readOnly] As Boolean, _
        ByVal displayText As String, _
        ByVal cellIsVisible As Boolean)

        Dim value As DateTime = _
        CType(GetColumnValueAtRow([source], rowNum), DateTime)
        If cellIsVisible Then
            customDateTimePicker1.Bounds = New Rectangle _
            (bounds.X + 2, bounds.Y + 2, bounds.Width - 4, _
            bounds.Height - 4)

            customDateTimePicker1.Value = value
            customDateTimePicker1.Visible = True
            AddHandler customDateTimePicker1.ValueChanged, _
            AddressOf TimePickerValueChanged
        Else
            customDateTimePicker1.Value = value
            customDateTimePicker1.Visible = False
        End If

        If customDateTimePicker1.Visible Then
            DataGridTableStyle.DataGrid.Invalidate(bounds)
        End If

        customDateTimePicker1.Focus()

    End Sub

    Protected Overrides Function GetPreferredSize( _
        ByVal g As Graphics, _
        ByVal value As Object) As Size

        Return New Size(100, customDateTimePicker1.PreferredHeight + 4)

    End Function

    Protected Overrides Function GetMinimumHeight() As Integer
        Return customDateTimePicker1.PreferredHeight + 4
    End Function

    Protected Overrides Function GetPreferredHeight( _
        ByVal g As Graphics, ByVal value As Object) As Integer

        Return customDateTimePicker1.PreferredHeight + 4

    End Function

    Protected Overloads Overrides Sub Paint( _
        ByVal g As Graphics, ByVal bounds As Rectangle, _
        ByVal [source] As CurrencyManager, ByVal rowNum As Integer)

        Paint(g, bounds, [source], rowNum, False)

    End Sub

    Protected Overloads Overrides Sub Paint(ByVal g As Graphics, _
        ByVal bounds As Rectangle, ByVal [source] As CurrencyManager, _
        ByVal rowNum As Integer, ByVal alignToRight As Boolean)

        Paint(g, bounds, [source], rowNum, Brushes.Red, _
            Brushes.Blue, alignToRight)

    End Sub

    Protected Overloads Overrides Sub Paint(ByVal g As Graphics, _
        ByVal bounds As Rectangle, ByVal [source] As CurrencyManager, _
        ByVal rowNum As Integer, ByVal backBrush As Brush, _
        ByVal foreBrush As Brush, ByVal alignToRight As Boolean)

        Dim [date] As DateTime = _
        CType(GetColumnValueAtRow([source], rowNum), DateTime)
        Dim rect As Rectangle = bounds
        g.FillRectangle(backBrush, rect)
        rect.Offset(0, 2)
        rect.Height -= 2
        g.DrawString([date].ToString("d"), _
            Me.DataGridTableStyle.DataGrid.Font, foreBrush, _
            RectangleF.FromLTRB(rect.X, rect.Y, rect.Right, rect.Bottom))

    End Sub

    Protected Overrides Sub SetDataGridInColumn(ByVal value As DataGrid)
        MyBase.SetDataGridInColumn(value)
        If (customDateTimePicker1.Parent IsNot Nothing) Then
            customDateTimePicker1.Parent.Controls.Remove(customDateTimePicker1)
        End If
        If (value IsNot Nothing) Then
            value.Controls.Add(customDateTimePicker1)
        End If
    End Sub

    Private Sub TimePickerValueChanged( _
        ByVal sender As Object, ByVal e As EventArgs)

        ' Remove the handler to prevent it from being called twice in a row.
        RemoveHandler customDateTimePicker1.ValueChanged, _
            AddressOf TimePickerValueChanged
        Me.isEditing = True
        MyBase.ColumnStartedEditing(customDateTimePicker1)

    End Sub

End Class

Public Class CustomDateTimePicker
    Inherits DateTimePicker

    <SecurityPermissionAttribute( _
    SecurityAction.LinkDemand, Flags := SecurityPermissionFlag.UnmanagedCode)> _
    Protected Overrides Function ProcessKeyMessage(ByRef m As Message) As Boolean
        ' Keep all the keys for the DateTimePicker.
        Return ProcessKeyEventArgs(m)
    End Function

End Class

Public Class MyForm
    Inherits Form

    Private namesDataTable As DataTable
    Private myGrid As DataGrid = New DataGrid()

    Public Sub New()

        InitForm()

        namesDataTable = New DataTable("NamesTable")
        namesDataTable.Columns.Add(New DataColumn("Name"))
        Dim dateColumn As DataColumn = _
             New DataColumn("Date", GetType(DateTime))
        dateColumn.DefaultValue = DateTime.Today
        namesDataTable.Columns.Add(dateColumn)
        Dim namesDataSet As DataSet = New DataSet()
        namesDataSet.Tables.Add(namesDataTable)
        myGrid.DataSource = namesDataSet
        myGrid.DataMember = "NamesTable"
        AddGridStyle()
        AddData()

    End Sub

    Private Sub AddGridStyle()
        Dim myGridStyle As DataGridTableStyle = _
                    New DataGridTableStyle()
        myGridStyle.MappingName = "NamesTable"

        Dim nameColumnStyle As DataGridTextBoxColumn = _
            New DataGridTextBoxColumn()
        nameColumnStyle.MappingName = "Name"
        nameColumnStyle.HeaderText = "Name"
        myGridStyle.GridColumnStyles.Add(nameColumnStyle)

        Dim customDateTimePicker1ColumnStyle As DataGridTimePickerColumn = _
            New DataGridTimePickerColumn()
        customDateTimePicker1ColumnStyle.MappingName = "Date"
        customDateTimePicker1ColumnStyle.HeaderText = "Date"
        customDateTimePicker1ColumnStyle.Width = 100
        myGridStyle.GridColumnStyles.Add(customDateTimePicker1ColumnStyle)

        myGrid.TableStyles.Add(myGridStyle)
    End Sub

    Private Sub AddData()
        Dim dRow As DataRow = namesDataTable.NewRow()
        dRow("Name") = "Name 1"
        dRow("Date") = New DateTime(2001, 12, 1)
        namesDataTable.Rows.Add(dRow)

        dRow = namesDataTable.NewRow()
        dRow("Name") = "Name 2"
        dRow("Date") = New DateTime(2001, 12, 4)
        namesDataTable.Rows.Add(dRow)

        dRow = namesDataTable.NewRow()
        dRow("Name") = "Name 3"
        dRow("Date") = New DateTime(2001, 12, 29)
        namesDataTable.Rows.Add(dRow)

        dRow = namesDataTable.NewRow()
        dRow("Name") = "Name 4"
        dRow("Date") = New DateTime(2001, 12, 13)
        namesDataTable.Rows.Add(dRow)

        dRow = namesDataTable.NewRow()
        dRow("Name") = "Name 5"
        dRow("Date") = New DateTime(2001, 12, 21)
        namesDataTable.Rows.Add(dRow)

        namesDataTable.AcceptChanges()
    End Sub

    Private Sub InitForm()
        Me.Size = New Size(500, 500)
        myGrid.Size = New Size(350, 250)
        myGrid.TabStop = True
        myGrid.TabIndex = 1
        Me.StartPosition = FormStartPosition.CenterScreen
        Me.Controls.Add(myGrid)
    End Sub

    <STAThread()> _
    Public Shared Sub Main()
        Application.Run(New MyForm())
    End Sub

End Class

Comentários

A coleção de DataGridColumnStyle objetos (o GridColumnStylesCollection) é acessada por meio da System.Windows.Forms.DataGrid propriedade do TableStyles controle.

O System.Windows.Forms.DataGrid controle cria automaticamente uma coleção de objetos para você quando você define a DataSource propriedade como uma fonte de DataGridColumnStyle dados apropriada. Os objetos criados são, na verdade, instâncias de uma das seguintes classes que herdam de DataGridColumnStyle: DataGridBoolColumn ou DataGridTextBoxColumn classe .

Para formatar a exibição de dados, defina a Format propriedade da DataGridTextBoxColumn classe como um dos valores de formatação. Para obter mais informações sobre valores de formatação válidos, consulte Tipos de formatação e Cadeias de caracteres de formato de data e hora personalizadas.

Você também pode criar seu próprio conjunto de DataGridColumnStyle objetos e adicioná-los ao GridColumnStylesCollection. Ao fazer isso, você deve definir o MappingName de cada estilo de coluna como o ColumnName de um DataColumn para sincronizar a exibição de colunas com os dados reais.

Quando uma das classes derivadas é instanciada por um System.Windows.Forms.DataGrid controle, a classe criada depende do DataTypeDataColumn associado ao DataGridColumnStyle objeto . Por exemplo, um DataColumn com seu DataType conjunto como System.Boolean será associado a um DataGridBoolColumn. Para determinar o tipo de qualquer DataGridColumnStyle, use o GetType método .

Para criar suas próprias classes de coluna, você pode herdar de DataGridColumnStyle. Talvez você queira fazer isso para criar colunas especiais que hospedam controles, conforme exemplificado pela DataGridTextBox classe , que hospeda o TextBox controle . Por exemplo, você pode hospedar um Image controle para mostrar imagens em colunas ou criar seu próprio controle de usuário para hospedar na coluna.

A funcionalidade do DataGridColumnStyle não deve ser confundida com a DataColumndo . Enquanto o DataColumn contém as propriedades e os métodos apropriados para criar o esquema de uma tabela de dados, o DataGridColumnStyle contém as propriedades e os métodos relacionados à aparência de uma coluna individual na tela.

Se uma linha contiver um DBNull.Value, o texto exibido na coluna poderá ser definido com a NullText propriedade .

A DataGridColumnStyle classe também permite que você especifique o comportamento de uma coluna enquanto seus dados estão sendo alterados. Os BeginUpdate métodos e EndUpdate suspendem temporariamente o desenho da coluna enquanto grandes atualizações estão sendo feitas nos dados da coluna. Sem essa funcionalidade, cada alteração em cada célula da grade seria imediatamente desenhada; isso pode ser uma distração para o usuário e uma responsabilidade de desempenho.

Vários métodos permitem o monitoramento da coluna conforme ela é editada pelo usuário, incluindo os Edit eventos e Commit .

A maioria das propriedades e métodos da classe são adaptados para controlar a aparência de uma coluna. Mas alguns, como e GetColumnValueAtRowSetColumnValueAtRow permitem que você examine e altere o valor em uma célula especificada.

Notas aos Implementadores

Ao herdar de DataGridColumnStyle, você deve substituir os seguintes membros: Abort(Int32), Commit(CurrencyManager, Int32), Edit(CurrencyManager, Int32, Rectangle, Boolean)e Paint(Graphics, Rectangle, CurrencyManager, Int32) (duas vezes).

Construtores

Propriedades

Métodos

Eventos

Implantações explícitas de interface

Aplica-se a

Confira também

• DataColumn
• DataGrid
• DataGridBoolColumn
• DataGridTextBox
• DataGridTableStyle
• DataView
• GridColumnStylesCollection