DataGrid.Columns Propriedade

Definição

Namespace:

System.Windows.Controls

Assembly:

PresentationFramework.dll

Obtém uma coleção que contém todas as colunas no DataGrid.

public:
 property System::Collections::ObjectModel::ObservableCollection<System::Windows::Controls::DataGridColumn ^> ^ Columns { System::Collections::ObjectModel::ObservableCollection<System::Windows::Controls::DataGridColumn ^> ^ get(); };

public System.Collections.ObjectModel.ObservableCollection<System.Windows.Controls.DataGridColumn> Columns { get; }

member this.Columns : System.Collections.ObjectModel.ObservableCollection<System.Windows.Controls.DataGridColumn>

Public ReadOnly Property Columns As ObservableCollection(Of DataGridColumn)

Valor da propriedade

ObservableCollection<DataGridColumn>

A coleção de colunas no DataGrid.

Exemplos

O exemplo a seguir mostra como adicionar uma coluna à coleção.

<!-- ItemsSource is a DataTable that contains a list of customers.  The DataTable columns are  
     Title, FirstName, MiddleName, LastName, Suffix, CompanyName, EmailAddress, and Phone.-->
<DataGrid Grid.Row="2" Name="DG2" ItemsSource="{Binding}" AutoGenerateColumns="False" />

public Window1()
{

Public Sub New()

    //Create a new column to add to the DataGrid
    DataGridTextColumn textcol = new DataGridTextColumn();
    //Create a Binding object to define the path to the DataGrid.ItemsSource property
    //The column inherits its DataContext from the DataGrid, so you don't set the source
    Binding b = new Binding("LastName");
    //Set the properties on the new column
    textcol.Binding = b;
    textcol.Header = "Last Name";
    //Add the column to the DataGrid
    DG2.Columns.Add(textcol);
}

    'Create a new column to add to the DataGrid
    Dim textcol As New DataGridTextColumn()
    'Create a Binding object to define the path to the DataGrid.ItemsSource property 
    'The column inherits its DataContext from the DataGrid, so you don't set the source
    Dim b As New Binding("LastName")
    'Set the properties on the new column
    textcol.Binding = b
    textcol.Header = "Last Name"
    'Add the column to the DataGrid

    DG2.Columns.Add(textcol)
End Sub

O exemplo a seguir mostra como remover uma coluna da coleção.

<Button Content="Delete First Column" Click="Button_Click" />

<!-- ItemsSource is a DataTable that contains a list of customers.  The DataTable columns are  
     Title, FirstName, MiddleName, LastName, Suffix, CompanyName, EmailAddress, and Phone.-->
<DataGrid Grid.Row="1" Name="DG1" ItemsSource="{Binding}" AutoGeneratingColumn="DG1_AutoGeneratingColumn"  />

private void Button_Click(object sender, RoutedEventArgs e)
{
    //Delete the first column whether visible or not
    DG1.Columns.RemoveAt(0);
}

Private Sub Button_Click(ByVal sender As Object, ByVal e As RoutedEventArgs)
    'Delete the first column whether visible or not
    DG1.Columns.RemoveAt(0)
End Sub

O exemplo a seguir mostra como definir propriedades em colunas na coleção quando elas são geradas automaticamente e quando um evento ocorre.

<CheckBox Content="View Customer Details" Checked="CheckBox_Checked" Unchecked="CheckBox_Unchecked" />

<!-- ItemsSource is a DataTable that contains a list of customers.  The DataTable columns are  
     Title, FirstName, MiddleName, LastName, Suffix, CompanyName, EmailAddress, and Phone.-->
<DataGrid Grid.Row="1" Name="DG1" ItemsSource="{Binding}" AutoGeneratingColumn="DG1_AutoGeneratingColumn"  />

private void DG1_AutoGeneratingColumn(object sender, DataGridAutoGeneratingColumnEventArgs e)
{
    //Set properties on the columns during auto-generation
    switch (e.Column.Header.ToString())
    {
        case "LastName":
            e.Column.CanUserSort = false;
            e.Column.Visibility = Visibility.Visible;
            break;
        case "FirstName":
            e.Column.Visibility = Visibility.Visible;
            break;
        case "CompanyName":
            e.Column.Visibility = Visibility.Visible;
            break;
        case "EmailAddress":
            e.Column.Visibility = Visibility.Visible;
            break;
        default:
            e.Column.Visibility = Visibility.Collapsed;
            break;
    }
}

private void CheckBox_Checked(object sender, RoutedEventArgs e)
{
    //Make each column in the collection visible
    foreach (DataGridColumn col in DG1.Columns)
    {
        col.Visibility = Visibility.Visible;
    }
}

private void CheckBox_Unchecked(object sender, RoutedEventArgs e)
{
    //Get the columns collection
    ObservableCollection<DataGridColumn> columns = DG1.Columns;

    //set the visibility for each column so only 4 columns are visible
    foreach (DataGridColumn col in columns)
    {
        switch (col.Header.ToString())
        {
            case "LastName":
                col.Visibility = Visibility.Visible;
                break;
            case "FirstName":
                col.Visibility = Visibility.Visible;
                break;
            case "CompanyName":
                col.Visibility = Visibility.Visible;
                break;
            case "EmailAddress":
                col.Visibility = Visibility.Visible;
                break;
            default:
                col.Visibility = Visibility.Collapsed;
                break;
        }
    }
}

Private Sub DG1_AutoGeneratingColumn(ByVal sender As Object, ByVal e As DataGridAutoGeneratingColumnEventArgs)
    'Set properties on the columns during auto-generation
    Select Case e.Column.Header.ToString()
        Case "LastName"
            e.Column.CanUserSort = False
            e.Column.Visibility = Visibility.Visible
            Exit Select
        Case "FirstName"
            e.Column.Visibility = Visibility.Visible
            Exit Select
        Case "CompanyName"
            e.Column.Visibility = Visibility.Visible
            Exit Select
        Case "EmailAddress"
            e.Column.Visibility = Visibility.Visible
            Exit Select
        Case Else
            e.Column.Visibility = Visibility.Collapsed
            Exit Select

    End Select
End Sub

Private Sub CheckBox_Checked(ByVal sender As Object, ByVal e As RoutedEventArgs)
    'Make each column in the collection visible
    For Each col As DataGridColumn In DG1.Columns
        col.Visibility = Visibility.Visible
    Next
End Sub

Private Sub CheckBox_Unchecked(ByVal sender As Object, ByVal e As RoutedEventArgs)
    'Get the columns collection
    Dim columns As ObservableCollection(Of DataGridColumn) = DG1.Columns

    'set the visibility for each column so only 4 columns are visible
    For Each col As DataGridColumn In columns
        Select Case col.Header.ToString()
            Case "LastName"
                col.Visibility = Visibility.Visible
                Exit Select
            Case "FirstName"
                col.Visibility = Visibility.Visible
                Exit Select
            Case "CompanyName"
                col.Visibility = Visibility.Visible
                Exit Select
            Case "EmailAddress"
                col.Visibility = Visibility.Visible
                Exit Select
            Case Else
                col.Visibility = Visibility.Collapsed
                Exit Select
        End Select

    Next
End Sub

Comentários

Use a Columns coleção para adicionar colunas, remover colunas ou atualizar propriedades nas colunas.

Observação

A ordem das colunas na coleção não determina a ordem em que elas serão exibidas DataGrid. A DisplayIndex propriedade determina a ordem da coluna.

Cada coluna na Columns coleção define uma coluna no DataGrid. A tabela a seguir lista os quatro tipos de coluna que o DataGrid fornece.

Tipo de coluna	Exibição de dados
DataGridHyperlinkColumn	Use para exibir dados de URI.
DataGridComboBoxColumn	Use para exibir dados de enumeração.
DataGridTextColumn	Use para exibir texto.
DataGridCheckBoxColumn	Use para exibir dados boolianos.

Além disso, você pode definir sua própria coluna personalizada usando DataGridTemplateColumn. As colunas na coleção devem derivar de DataGridColumn. Observe que DataGridBoundColumn, o que adiciona suporte à associação, deriva DataGridColumn e é a base para vários dos tipos de coluna definidos.

Todas as colunas da coleção usam a ItemsSource propriedade definida pelo DataGrid.

Você pode modificar a Columns coleção em tempo de execução, independentemente de ela conter colunas geradas.