DataGridViewCellErrorTextNeededEventArgs Classe

Définition

Fournit des données destinées à l'événement CellErrorTextNeeded d'un contrôle DataGridView.Provides data for the CellErrorTextNeeded event of a DataGridView control.

public ref class DataGridViewCellErrorTextNeededEventArgs : System::Windows::Forms::DataGridViewCellEventArgs
public class DataGridViewCellErrorTextNeededEventArgs : System.Windows.Forms.DataGridViewCellEventArgs
type DataGridViewCellErrorTextNeededEventArgs = class
    inherit DataGridViewCellEventArgs
Public Class DataGridViewCellErrorTextNeededEventArgs
Inherits DataGridViewCellEventArgs
Héritage
DataGridViewCellErrorTextNeededEventArgs

Exemples

Dans l’exemple de code suivant montre comment créer des messages d’erreur pour les cellules sans annuler le partage des lignes ou provoquer la duplication de l’erreur de cellule sur toutes les cellules partagées.In the following code example demonstrates how to create error messages for cells without unsharing rows or causing the cell error to be duplicated over all the shared cells.

ToolStripMenuItem^ wholeTable;
ToolStripMenuItem^ lookUp;
System::Windows::Forms::ContextMenuStrip^ strip;
String^ cellErrorText;

void dataGridView1_CellContextMenuStripNeeded( Object^ /*sender*/,
    DataGridViewCellContextMenuStripNeededEventArgs^ e )
{
    cellErrorText = String::Empty;
    if ( strip == nullptr )
    {
        strip = gcnew System::Windows::Forms::ContextMenuStrip;
        lookUp->Text = L"Look Up";
        wholeTable->Text = L"See Whole Table";
        strip->Items->Add( lookUp );
        strip->Items->Add( wholeTable );
    }

    e->ContextMenuStrip = strip;
}

void wholeTable_Click( Object^ /*sender*/, EventArgs^ /*e*/ )
{
    dataGridView1->DataSource = Populate( L"Select * from employees", true );
}

DataGridViewCellEventArgs^ theCellImHoveringOver;
void dataGridView1_CellMouseEnter( Object^ /*sender*/, DataGridViewCellEventArgs^ e )
{
    theCellImHoveringOver = e;
}

DataGridViewCellEventArgs^ cellErrorLocation;
void lookUp_Click( Object^ /*sender*/, EventArgs^ /*e*/ )
{
    try
    {
        dataGridView1->DataSource = Populate( String::Format( L"Select * from employees where {0} = '{1}'", dataGridView1->Columns[ theCellImHoveringOver->ColumnIndex ]->Name, dataGridView1->Rows[ theCellImHoveringOver->RowIndex ]->Cells[ theCellImHoveringOver->ColumnIndex ]->Value ), true );
    }
    catch ( ... ) 
    {
        cellErrorText = L"Can't look this cell up";
        cellErrorLocation = theCellImHoveringOver;
    }

}

void dataGridView1_CellErrorTextNeeded( Object^ /*sender*/, DataGridViewCellErrorTextNeededEventArgs^ e )
{
    if ( cellErrorLocation != nullptr )
    {
        if ( e->ColumnIndex == cellErrorLocation->ColumnIndex && e->RowIndex == cellErrorLocation->RowIndex )
        {
            e->ErrorText = cellErrorText;
        }
    }
}

DataTable^ Populate( String^ query, bool resetUnsharedCounter )
{
    if ( resetUnsharedCounter )
    {
        ResetCounter();
    }


    // Alter the data source as necessary
    SqlDataAdapter^ adapter = gcnew SqlDataAdapter( query,
        gcnew SqlConnection( L"Integrated Security=SSPI;Persist Security Info=False;"
        L"Initial Catalog=Northwind;Data Source= localhost" ) );
    DataTable^ table = gcnew DataTable;
    adapter->Fill( table );
    return table;
}

Label^ count;
int unsharedRowCounter;
void ResetCounter()
{
    unsharedRowCounter = 0;
    count->Text = unsharedRowCounter.ToString();
}
private ToolStripMenuItem wholeTable = new ToolStripMenuItem();
private ToolStripMenuItem lookUp = new ToolStripMenuItem();
private ContextMenuStrip strip;
private string cellErrorText;

private void dataGridView1_CellContextMenuStripNeeded(object sender,
    DataGridViewCellContextMenuStripNeededEventArgs e)
{
    cellErrorText = String.Empty;

    if (strip == null)
    {
        strip = new ContextMenuStrip();
        lookUp.Text = "Look Up";
        wholeTable.Text = "See Whole Table";
        strip.Items.Add(lookUp);
        strip.Items.Add(wholeTable);
    }
    e.ContextMenuStrip = strip;
}

private void wholeTable_Click(object sender, EventArgs e)
{
    dataGridView1.DataSource = Populate("Select * from employees", true);
}

private DataGridViewCellEventArgs theCellImHoveringOver;

private void dataGridView1_CellMouseEnter(object sender, DataGridViewCellEventArgs e)
{
    theCellImHoveringOver = e;
}

private DataGridViewCellEventArgs cellErrorLocation;

private void lookUp_Click(object sender, EventArgs e)
{
    try
    {
        dataGridView1.DataSource = Populate("Select * from employees where " +
            dataGridView1.Columns[theCellImHoveringOver.ColumnIndex].Name + " = '" +
            dataGridView1.Rows[theCellImHoveringOver.RowIndex].
            Cells[theCellImHoveringOver.ColumnIndex].Value + "'",
            true);
    }
    catch (SqlException)
    {
        cellErrorText = "Can't look this cell up";
        cellErrorLocation = theCellImHoveringOver;
    }
}

private void dataGridView1_CellErrorTextNeeded(object sender,
    DataGridViewCellErrorTextNeededEventArgs e)
{
    if (cellErrorLocation != null)
    {
        if (e.ColumnIndex == cellErrorLocation.ColumnIndex &&
            e.RowIndex == cellErrorLocation.RowIndex)
        {
            e.ErrorText = cellErrorText;
        }
    }
}

private DataTable Populate(string query, bool resetUnsharedCounter)
{
    if (resetUnsharedCounter)
    {
        ResetCounter();
    }

    // Alter the data source as necessary
    SqlDataAdapter adapter = new SqlDataAdapter(query,
        new SqlConnection("Integrated Security=SSPI;Persist Security Info=False;" +
        "Initial Catalog=Northwind;Data Source=localhost"));

    DataTable table = new DataTable();
    table.Locale = System.Globalization.CultureInfo.InvariantCulture;
    adapter.Fill(table);
    return table;
}

private Label count = new Label();
private int unsharedRowCounter;

private void ResetCounter()
{
    unsharedRowCounter = 0;
    count.Text = unsharedRowCounter.ToString();
}
Private WithEvents wholeTable As New ToolStripMenuItem()
Private WithEvents lookUp As New ToolStripMenuItem()
Private strip As ContextMenuStrip
Private cellErrorText As String

Private Sub dataGridView1_CellContextMenuStripNeeded(ByVal sender As Object, _
    ByVal e As DataGridViewCellContextMenuStripNeededEventArgs) _
    Handles dataGridView1.CellContextMenuStripNeeded

    cellErrorText = String.Empty

    If strip Is Nothing Then
        strip = New ContextMenuStrip()
        lookUp.Text = "Look Up"
        wholeTable.Text = "See Whole Table"
        strip.Items.Add(lookUp)
        strip.Items.Add(wholeTable)
    End If
    e.ContextMenuStrip = strip
End Sub

Private Sub wholeTable_Click(ByVal sender As Object, ByVal e As EventArgs) Handles wholeTable.Click
    dataGridView1.DataSource = Populate("Select * from employees", True)
End Sub

Private theCellImHoveringOver As DataGridViewCellEventArgs

Private Sub dataGridView1_CellMouseEnter(ByVal sender As Object, _
    ByVal e As DataGridViewCellEventArgs) _
    Handles dataGridView1.CellMouseEnter

    theCellImHoveringOver = e
End Sub

Private cellErrorLocation As DataGridViewCellEventArgs

Private Sub lookUp_Click(ByVal sender As Object, ByVal e As EventArgs) Handles lookUp.Click
    Try
        dataGridView1.DataSource = Populate("Select * from employees where " & _
            dataGridView1.Columns(theCellImHoveringOver.ColumnIndex).Name & " = '" & _
            dataGridView1.Rows(theCellImHoveringOver.RowIndex).Cells(theCellImHoveringOver.ColumnIndex).Value.ToString() & _
            "'", True)
    Catch ex As SqlException
        cellErrorText = "Can't look this cell up"
        cellErrorLocation = theCellImHoveringOver
    End Try
End Sub

Private Sub dataGridView1_CellErrorTextNeeded(ByVal sender As Object, _
            ByVal e As DataGridViewCellErrorTextNeededEventArgs) _
            Handles dataGridView1.CellErrorTextNeeded
    If (Not cellErrorLocation Is Nothing) Then
        If e.ColumnIndex = cellErrorLocation.ColumnIndex AndAlso _
            e.RowIndex = cellErrorLocation.RowIndex Then
            e.ErrorText = cellErrorText
        End If
    End If
End Sub

Private Function Populate(ByVal query As String, ByVal resetUnsharedCounter As Boolean) As DataTable

    If resetUnsharedCounter Then
        ResetCounter()
    End If

    ' Alter the data source as necessary
    Dim adapter As New SqlDataAdapter(query, _
        New SqlConnection("Integrated Security=SSPI;Persist Security Info=False;" & _
        "Initial Catalog=Northwind;Data Source=localhost"))

    Dim table As New DataTable()
    table.Locale = System.Globalization.CultureInfo.InvariantCulture
    adapter.Fill(table)
    Return table
End Function

Private count As New Label()
Private unsharedRowCounter As Integer

Private Sub ResetCounter()
    unsharedRowCounter = 0
    count.Text = unsharedRowCounter.ToString()
End Sub

Remarques

L' CellErrorTextNeeded événement se produit uniquement lorsque DataGridView la DataSource propriété du contrôle est définie VirtualMode ou que truesa propriété est.The CellErrorTextNeeded event occurs only when the DataGridView control DataSource property is set or its VirtualMode property is true. La gestion CellErrorTextNeeded de l’événement est utile lorsque vous souhaitez déterminer l’erreur d’une cellule en fonction de sa valeur ou de son état.Handling the CellErrorTextNeeded event is useful when you want to determine the error for a cell depending on its value or state.

Lorsque vous gérez l' CellErrorTextNeeded événement et spécifiez le texte d’erreur dans le gestionnaire, un glyphe d’erreur apparaît dans DataGridView.ShowCellErrors la cellule, sauf false si la propriété a la valeur ou si la cellule est en mode édition.When you handle the CellErrorTextNeeded event and specify error text in the handler, an error glyph appears in the cell unless the DataGridView.ShowCellErrors property is set to false or the cell is in edit mode. Lorsque l’utilisateur déplace le pointeur de la souris sur le glyphe d’erreur, le texte d’erreur s’affiche dans une info-bulle.When the user moves the mouse pointer over the error glyph, the error text appears in a ToolTip.

L' CellErrorTextNeeded événement se produit également chaque fois que la DataGridViewCell.ErrorText valeur de la propriété est récupérée.The CellErrorTextNeeded event also occurs whenever the value of the DataGridViewCell.ErrorText property is retrieved.

Vous pouvez utiliser la DataGridViewCellEventArgs.RowIndex propriété ColumnIndex et pour déterminer l’État ou la valeur d’une cellule, et utiliser ces informations pour modifier ou modifier DataGridViewCellErrorTextNeededEventArgs.ErrorText la propriété.You can use the DataGridViewCellEventArgs.RowIndex and ColumnIndex property to determine the state or value of a cell, and use this information to change or modify the DataGridViewCellErrorTextNeededEventArgs.ErrorText property. Cette propriété est initialisée avec la valeur de la propriété ErrorText de cellule, que la valeur d’événement remplace.This property is initialized with the value of the cell ErrorText property, which the event value overrides.

Gérez l' CellErrorTextNeeded événement lorsque vous travaillez avec de grandes quantités de données pour éviter les pénalités de performances ErrorText de la définition de la valeur de cellule pour plusieurs cellules.Handle the CellErrorTextNeeded event when working with large amounts of data to avoid the performance penalties of setting the cell ErrorText value for multiple cells. Pour plus d'informations, consultez Meilleures pratiques pour la mise à l'échelle du contrôle DataGridView Windows Forms.For more information, see Best Practices for Scaling the Windows Forms DataGridView Control.

Pour plus d’informations sur la façon de gérer les événements, consultez gestion et déclenchement d’événements.For more information about how to handle events, see Handling and Raising Events.

Propriétés

ColumnIndex

Obtient une valeur indiquant l'index de colonne de la cellule sur lequel se produit l'événement.Gets a value indicating the column index of the cell that the event occurs for.

(Hérité de DataGridViewCellEventArgs)
ErrorText

Obtient ou définit le message affiché quand la cellule est sélectionnée.Gets or sets the message that is displayed when the cell is selected.

RowIndex

Obtient une valeur indiquant l'index de ligne de la cellule sur lequel se produit l'événement.Gets a value indicating the row index of the cell that the event occurs for.

(Hérité de DataGridViewCellEventArgs)

Méthodes

Equals(Object)

Détermine si l'objet spécifié est égal à l'objet actuel.Determines whether the specified object is equal to the current object.

(Hérité de Object)
GetHashCode()

Sert de fonction de hachage par défaut.Serves as the default hash function.

(Hérité de Object)
GetType()

Obtient le Type de l'instance actuelle.Gets the Type of the current instance.

(Hérité de Object)
MemberwiseClone()

Crée une copie superficielle du Object actuel.Creates a shallow copy of the current Object.

(Hérité de Object)
ToString()

Retourne une chaîne qui représente l'objet actif.Returns a string that represents the current object.

(Hérité de Object)

S’applique à

Voir aussi