Procedura: Elencare i formati di dati in un oggetto dati

Negli esempi seguenti viene illustrato come usare gli overload del metodo GetFormats ottenere una matrice di stringhe che denotano ogni formato di dati disponibile in un oggetto dati.

Sovraccarico GetFormats() per tutti i formati di dati

Descrizione

Il codice di esempio seguente usa l'overload GetFormats per ottenere una matrice di stringhe che denota tutti i formati di dati disponibili in un oggetto dati (sia nativo che convertibile automaticamente).

Codice

DataObject dataObject = new DataObject("Some string data to store...");

// Get an array of strings, each string denoting a data format
// that is available in the data object.  This overload of GetDataFormats
// returns all available data formats, native and auto-convertible.
string[] dataFormats = dataObject.GetFormats();

// Get the number of data formats present in the data object, including both
// auto-convertible and native data formats.
int numberOfDataFormats = dataFormats.Length;

// To enumerate the resulting array of data formats, and take some action when
// a particular data format is found, use a code structure similar to the following.
foreach (string dataFormat in dataFormats)
{
    if (dataFormat == DataFormats.Text)
    {
        // Take some action if/when data in the Text data format is found.
        break;
    }
    else if(dataFormat == DataFormats.StringFormat)
    {
        // Take some action if/when data in the string data format is found.
        break;
    }
}

Dim dataObject As New DataObject("Some string data to store...")

' Get an array of strings, each string denoting a data format
' that is available in the data object.  This overload of GetDataFormats
' returns all available data formats, native and auto-convertible.
Dim dataFormats() As String = dataObject.GetFormats()

' Get the number of data formats present in the data object, including both
' auto-convertible and native data formats.
Dim numberOfDataFormats As Integer = dataFormats.Length

' To enumerate the resulting array of data formats, and take some action when
' a particular data format is found, use a code structure similar to the following.
For Each dataFormat As String In dataFormats
    If dataFormat = System.Windows.DataFormats.Text Then
        ' Take some action if/when data in the Text data format is found.
        Exit For
    ElseIf dataFormat = System.Windows.DataFormats.StringFormat Then
        ' Take some action if/when data in the string data format is found.
        Exit For
    End If
Next dataFormat

L'overload di GetFormats() per i formati di dati nativi

Descrizione

Il codice di esempio seguente usa l'overload GetFormats per ottenere una matrice di stringhe che denota solo i formati di dati disponibili in un oggetto dati (i formati di dati convertibili automaticamente vengono filtrati).

Codice

DataObject dataObject = new DataObject("Some string data to store...");

// Get an array of strings, each string denoting a data format
// that is available in the data object.  This overload of GetDataFormats
// accepts a Boolean parameter inidcating whether to include auto-convertible
// data formats, or only return native data formats.
string[] dataFormats = dataObject.GetFormats(false /* Include auto-convertible? */);

// Get the number of native data formats present in the data object.
int numberOfDataFormats = dataFormats.Length;

// To enumerate the resulting array of data formats, and take some action when
// a particular data format is found, use a code structure similar to the following.
foreach (string dataFormat in dataFormats)
{
    if (dataFormat == DataFormats.Text)
    {
        // Take some action if/when data in the Text data format is found.
        break;
    }
}

Dim dataObject As New DataObject("Some string data to store...")

' Get an array of strings, each string denoting a data format
' that is available in the data object.  This overload of GetDataFormats
' accepts a Boolean parameter inidcating whether to include auto-convertible
' data formats, or only return native data formats.
Dim dataFormats() As String = dataObject.GetFormats(False) ' Include auto-convertible? 

' Get the number of native data formats present in the data object.
Dim numberOfDataFormats As Integer = dataFormats.Length

' To enumerate the resulting array of data formats, and take some action when
' a particular data format is found, use a code structure similar to the following.
For Each dataFormat As String In dataFormats
    If dataFormat = System.Windows.DataFormats.Text Then
        ' Take some action if/when data in the Text data format is found.
        Exit For
    End If
Next dataFormat

Vedere anche

• IDataObject
• Panoramica delle funzionalità di trascinamento e rilascio