DataView.ToTable Methode

Referenz

Definition

Namespace:: System.Data

Assembly:: System.Data.Common.dll

Assembly:: System.Data.dll

Assembly:: netstandard.dll

Wichtig

Einige Informationen beziehen sich auf Vorabversionen, die vor dem Release ggf. grundlegend überarbeitet werden. Microsoft übernimmt hinsichtlich der hier bereitgestellten Informationen keine Gewährleistungen, seien sie ausdrücklich oder konkludent.

Erstellt eine neue DataTable basierend auf den Zeilen in einer vorhandenen DataView und gibt diese zurück.

Überlädt

ToTable(Boolean, String[])	Erstellt eine neue DataTable basierend auf den Zeilen in einer vorhandenen DataView und gibt diese zurück.
ToTable(String)	Erstellt eine neue DataTable basierend auf den Zeilen in einer vorhandenen DataView und gibt diese zurück.
ToTable(String, Boolean, String[])	Erstellt eine neue DataTable basierend auf den Zeilen in einer vorhandenen DataView und gibt diese zurück.
ToTable()	Erstellt eine neue DataTable basierend auf den Zeilen in einer vorhandenen DataView und gibt diese zurück.

Hinweise

Der zurückgegebene DataTable Wert behält die Werte der folgenden Eigenschaften aus der Quelle DataTablebei: Namespace, Prefix, Locale, und CaseSensitive. Jede Spalte im Ergebnis DataTable enthält eine identische Kopie aller entsprechenden Eigenschaften in der zugrunde liegenden DataTable.

Die DataRow Instanzen in der zurückgegebenen DataTable Datei enthalten Werte, die mit der CLR-Semantik übereinstimmen. Das heißt, für alle Datentypen neben benutzerdefinierten Typen werden die entsprechenden Spaltenwerte nach Wert kopiert. Bei benutzerdefinierten Datentypen werden die Spaltendaten nach Verweis kopiert.

ToTable(Boolean, String[])

Erstellt eine neue DataTable basierend auf den Zeilen in einer vorhandenen DataView und gibt diese zurück.

public:
 System::Data::DataTable ^ ToTable(bool distinct, ... cli::array <System::String ^> ^ columnNames);

public System.Data.DataTable ToTable (bool distinct, params string[] columnNames);

member this.ToTable : bool * string[] -> System.Data.DataTable

Public Function ToTable (distinct As Boolean, ParamArray columnNames As String()) As DataTable

Parameter

distinct: Boolean

Wenn auf true festgelegt, enthält die zurückgegebene DataTable Zeilen mit unterschiedlichen Werten für alle Spalten. Der Standardwert ist false.

columnNames: String[]

Ein Zeichenfolgenarray mit einer Liste der Spaltennamen, die in der zurückgegebenen DataTable enthalten sein sollen. Die DataTable enthält die angegebenen Spalten in der Reihenfolge, in der sie in diesem Array angezeigt werden.

Gibt zurück

DataTable

Eine neue DataTable-Instanz, die die angeforderten Zeilen und Spalten enthält.

Beispiele

Das folgende Konsolenanwendungsbeispiel erstellt eine DataTable, füllt die DataTable Daten aus, sortiert das DataViewUnd erstellt schließlich eine DataTable mit nur zwei Spalten beschränkte Zeilen, in denen alle Werte eindeutig sind.

private static void DemonstrateDataView()
{
    // Create a DataTable with three columns.
    DataTable table = new DataTable("NewTable");
    Console.WriteLine("Original table name: " + table.TableName);
    DataColumn column = new DataColumn("ID", typeof(System.Int32));
    table.Columns.Add(column);

    column = new DataColumn("Category", typeof(System.String));
    table.Columns.Add(column);

    column = new DataColumn("Product", typeof(System.String));
    table.Columns.Add(column);

    column = new DataColumn("QuantityInStock", typeof(System.Int32));
    table.Columns.Add(column);

    // Add some items.
    DataRow row = table.NewRow();
    row.ItemArray = new object[] { 1, "Fruit", "Apple", 14 };
    table.Rows.Add(row);

    row = table.NewRow();
    row.ItemArray = new object[] { 2, "Fruit", "Orange", 27 };
    table.Rows.Add(row);

    row = table.NewRow();
    row.ItemArray = new object[] { 3, "Bread", "Muffin", 23 };
    table.Rows.Add(row);

    row = table.NewRow();
    row.ItemArray = new object[] { 4, "Fish", "Salmon", 12 };
    table.Rows.Add(row);

    row = table.NewRow();
    row.ItemArray = new object[] { 5, "Fish", "Salmon", 15 };
    table.Rows.Add(row);

    row = table.NewRow();
    row.ItemArray = new object[] { 6, "Bread", "Croissant", 23};
    table.Rows.Add(row);

    // Mark all rows as "accepted". Not required
    // for this particular example.
    table.AcceptChanges();

    // Print current table values.
    PrintTableOrView(table, "Current Values in Table");

    DataView view = new DataView(table);
    view.Sort = "Category";
    PrintTableOrView(view, "Current Values in View");

    DataTable newTable = view.ToTable(true, "Category", "QuantityInStock");
    PrintTableOrView(newTable, "Table created from sorted DataView");
    Console.WriteLine("New table name: " + newTable.TableName);

    Console.WriteLine("Press any key to continue.");
    Console.ReadKey();
}

private static void PrintTableOrView(DataView dv, string label)
{
    System.IO.StringWriter sw;
    string output;
    DataTable table = dv.Table;

    Console.WriteLine(label);

    // Loop through each row in the view.
    foreach (DataRowView rowView in dv)
    {
        sw = new System.IO.StringWriter();

        // Loop through each column.
        foreach (DataColumn col in table.Columns)
        {
            // Output the value of each column's data.
            sw.Write(rowView[col.ColumnName].ToString() + ", ");
        }
        output = sw.ToString();
        // Trim off the trailing ", ", so the output looks correct.
        if (output.Length > 2)
        {
            output = output.Substring(0, output.Length - 2);
        }
        // Display the row in the console window.
        Console.WriteLine(output);
    }
    Console.WriteLine();
}

private static void PrintTableOrView(DataTable table, string label)
{
    System.IO.StringWriter sw;
    string output;

    Console.WriteLine(label);

    // Loop through each row in the table.
    foreach (DataRow row in table.Rows)
    {
        sw = new System.IO.StringWriter();
        // Loop through each column.
        foreach (DataColumn col in table.Columns)
        {
            // Output the value of each column's data.
            sw.Write(row[col].ToString() + ", ");
        }
        output = sw.ToString();
        // Trim off the trailing ", ", so the output looks correct.
        if (output.Length > 2)
        {
            output = output.Substring(0, output.Length - 2);
        }
        // Display the row in the console window.
        Console.WriteLine(output);
    }
    Console.WriteLine();
}

Private Sub DemonstrateDataView()
    ' Create a DataTable with three columns.
    Dim table As New DataTable("NewTable")
    Console.WriteLine("Original table name: " & table.TableName)
    Dim column As New DataColumn("ID", GetType(System.Int32))
    table.Columns.Add(column)

    column = New DataColumn("Category", GetType(System.String))
    table.Columns.Add(column)

    column = New DataColumn("Product", GetType(System.String))
    table.Columns.Add(column)

    column = New DataColumn("QuantityInStock", GetType(System.Int32))
    table.Columns.Add(column)


    ' Add some items.
    Dim row As DataRow = table.NewRow()
    row.ItemArray = New Object() {1, "Fruit", "Apple", 14}
    table.Rows.Add(row)

    row = table.NewRow()
    row.ItemArray = New Object() {2, "Fruit", "Orange", 27}
    table.Rows.Add(row)

    row = table.NewRow()
    row.ItemArray = New Object() {3, "Bread", "Muffin", 23}
    table.Rows.Add(row)

    row = table.NewRow()
    row.ItemArray = New Object() {4, "Fish", "Salmon", 12}
    table.Rows.Add(row)

    row = table.NewRow()
    row.ItemArray = New Object() {5, "Fish", "Salmon", 15}
    table.Rows.Add(row)

    row = table.NewRow()
    row.ItemArray = New Object() {6, "Bread", "Croissant", 23}
    table.Rows.Add(row)

    ' Mark all rows as "accepted". Not required
    ' for this particular example.
    table.AcceptChanges()

    ' Print current table values.
    PrintTableOrView(table, "Current Values in Table")

    Dim view As New DataView(table)
    view.Sort = "Category"
    PrintTableOrView(view, "Current Values in View")

    Dim newTable As DataTable = view.ToTable( _
        True, "Category", "QuantityInStock")
    PrintTableOrView(newTable, "Table created from sorted DataView")
    Console.WriteLine("New table name: " & newTable.TableName)

    Console.WriteLine("Press any key to continue.")
    Console.ReadKey()
End Sub

Private Sub PrintTableOrView(ByVal dv As DataView, ByVal label As String)
    Dim sw As System.IO.StringWriter
    Dim output As String
    Dim table As DataTable = dv.Table

    Console.WriteLine(label)

    ' Loop through each row in the view.
    For Each rowView As DataRowView In dv
        sw = New System.IO.StringWriter

        ' Loop through each column.
        For Each col As DataColumn In table.Columns
            ' Output the value of each column's data.
            sw.Write(rowView(col.ColumnName).ToString() & ", ")
        Next
        output = sw.ToString
        ' Trim off the trailing ", ", so the output looks correct.
        If output.Length > 2 Then
            output = output.Substring(0, output.Length - 2)
        End If
        ' Display the row in the console window.
        Console.WriteLine(output)
    Next
    Console.WriteLine()
End Sub

Private Sub PrintTableOrView(ByVal table As DataTable, ByVal label As String)
    Dim sw As System.IO.StringWriter
    Dim output As String

    Console.WriteLine(label)

    ' Loop through each row in the table.
    For Each row As DataRow In table.Rows
        sw = New System.IO.StringWriter
        ' Loop through each column.
        For Each col As DataColumn In table.Columns
            ' Output the value of each column's data.
            sw.Write(row(col).ToString() & ", ")
        Next
        output = sw.ToString
        ' Trim off the trailing ", ", so the output looks correct.
        If output.Length > 2 Then
            output = output.Substring(0, output.Length - 2)
        End If
        ' Display the row in the console window.
        Console.WriteLine(output)
    Next
    Console.WriteLine()
End Sub

Im Beispiel wird die folgende Ausgabe im Konsolenfenster angezeigt:

Original table name: NewTable  
Current Values in Table  
1, Fruit, Apple, 14  
2, Fruit, Orange, 27  
3, Bread, Muffin, 23  
4, Fish, Salmon, 12  
5, Fish, Salmon, 15  
6, Bread, Croissant, 23  

Current Values in View  
3, Bread, Muffin, 23  
6, Bread, Croissant, 23  
4, Fish, Salmon, 12  
5, Fish, Salmon, 15  
1, Fruit, Apple, 14  
2, Fruit, Orange, 27  

Table created from sorted DataView  
Bread, 23  
Fish, 12  
Fish, 15  
Fruit, 14  
Fruit, 27  

New table name: NewTable

Hinweise

Da diese Methode den Namen für die Ausgabe DataTablenicht angeben lässt, entspricht der Name der Quelle dem Namen der Quelle DataTable.

Gilt für

ToTable(String)

Erstellt eine neue DataTable basierend auf den Zeilen in einer vorhandenen DataView und gibt diese zurück.

public:
 System::Data::DataTable ^ ToTable(System::String ^ tableName);

public System.Data.DataTable ToTable (string? tableName);

public System.Data.DataTable ToTable (string tableName);

member this.ToTable : string -> System.Data.DataTable

Public Function ToTable (tableName As String) As DataTable

Parameter

tableName: String

Der Name der zurückgegebenen DataTable.

Gibt zurück

DataTable

Eine neue DataTable-Instanz, die die angeforderten Zeilen und Spalten enthält.

Beispiele

Das folgende Konsolenanwendungsbeispiel erstellt eine DataTable, füllt die DataTable Daten aus, erstellt eine gefilterte Ansicht basierend auf den ursprünglichen Daten und erstellt schließlich einen DataTable neuen Namen, der die gefilterten Zeilen enthält.

private static void DemonstrateDataView()
{
    // Create a DataTable with three columns.
    DataTable table = new DataTable("NewTable");
    Console.WriteLine("Original table name: " + table.TableName);
    DataColumn column = new DataColumn("ID", typeof(System.Int32));
    table.Columns.Add(column);

    column = new DataColumn("Category", typeof(System.String));
    table.Columns.Add(column);

    column = new DataColumn("Product", typeof(System.String));
    table.Columns.Add(column);

    column = new DataColumn("QuantityInStock", typeof(System.Int32));
    table.Columns.Add(column);

    // Add some items.
    DataRow row = table.NewRow();
    row.ItemArray = new object[] { 1, "Fruit", "Apple", 14 };
    table.Rows.Add(row);

    row = table.NewRow();
    row.ItemArray = new object[] { 2, "Fruit", "Orange", 27 };
    table.Rows.Add(row);

    row = table.NewRow();
    row.ItemArray = new object[] { 3, "Bread", "Muffin", 23 };
    table.Rows.Add(row);

    row = table.NewRow();
    row.ItemArray = new object[] { 4, "Fish", "Salmon", 12 };
    table.Rows.Add(row);

    // Mark all rows as "accepted". Not really required
    // for this particular example.
    table.AcceptChanges();

    // Print current table values.
    PrintTableOrView(table, "Current Values in Table");

    DataView view = new DataView(table);
    view.RowFilter = "QuantityInStock > 15";
    PrintTableOrView(view, "Current Values in View");

    DataTable newTable = view.ToTable("FilteredTable");
    PrintTableOrView(newTable, "Table created from filtered DataView");
    Console.WriteLine("New table name: " + newTable.TableName);

    Console.WriteLine("Press any key to continue.");
    Console.ReadKey();
}

private static void PrintTableOrView(DataView dv, string label)
{
    System.IO.StringWriter sw;
    string output;
    DataTable table = dv.Table;

    Console.WriteLine(label);

    // Loop through each row in the view.
    foreach (DataRowView rowView in dv)
    {
        sw = new System.IO.StringWriter();

        // Loop through each column.
        foreach (DataColumn col in table.Columns)
        {
            // Output the value of each column's data.
            sw.Write(rowView[col.ColumnName].ToString() + ", ");
        }
        output = sw.ToString();
        // Trim off the trailing ", ", so the output looks correct.
        if (output.Length > 2)
        {
            output = output.Substring(0, output.Length - 2);
        }
        // Display the row in the console window.
        Console.WriteLine(output);
    }
    Console.WriteLine();
}

private static void PrintTableOrView(DataTable table, string label)
{
    System.IO.StringWriter sw;
    string output;

    Console.WriteLine(label);

    // Loop through each row in the table.
    foreach (DataRow row in table.Rows)
    {
        sw = new System.IO.StringWriter();
        // Loop through each column.
        foreach (DataColumn col in table.Columns)
        {
            // Output the value of each column's data.
            sw.Write(row[col].ToString() + ", ");
        }
        output = sw.ToString();
        // Trim off the trailing ", ", so the output looks correct.
        if (output.Length > 2)
        {
            output = output.Substring(0, output.Length - 2);
        }
        // Display the row in the console window.
        Console.WriteLine(output);
    }
    Console.WriteLine();
}

Private Sub DemonstrateDataView()
    ' Create a DataTable with three columns.
    Dim table As New DataTable("NewTable")
    Console.WriteLine("Original table name: " & table.TableName)
    Dim column As New DataColumn("ID", GetType(System.Int32))
    table.Columns.Add(column)

    column = New DataColumn("Category", GetType(System.String))
    table.Columns.Add(column)

    column = New DataColumn("Product", GetType(System.String))
    table.Columns.Add(column)

    column = New DataColumn("QuantityInStock", GetType(System.Int32))
    table.Columns.Add(column)


    ' Add some items.
    Dim row As DataRow = table.NewRow()
    row.ItemArray = New Object() {1, "Fruit", "Apple", 14}
    table.Rows.Add(row)

    row = table.NewRow()
    row.ItemArray = New Object() {2, "Fruit", "Orange", 27}
    table.Rows.Add(row)

    row = table.NewRow()
    row.ItemArray = New Object() {3, "Bread", "Muffin", 23}
    table.Rows.Add(row)

    row = table.NewRow()
    row.ItemArray = New Object() {4, "Fish", "Salmon", 12}
    table.Rows.Add(row)

    ' Mark all rows as "accepted". Not required
    ' for this particular example.
    table.AcceptChanges()

    ' Print current table values.
    PrintTableOrView(table, "Current Values in Table")

    Dim view As New DataView(table)
    view.RowFilter = "QuantityInStock > 15"
    PrintTableOrView(view, "Current Values in View")

    Dim newTable As DataTable = view.ToTable("FilteredTable")
    PrintTableOrView(newTable, "Table created from filtered DataView")
    Console.WriteLine("New table name: " & newTable.TableName)

    Console.WriteLine("Press any key to continue.")
    Console.ReadKey()
End Sub

Private Sub PrintTableOrView(ByVal dv As DataView, ByVal label As String)
    Dim sw As System.IO.StringWriter
    Dim output As String
    Dim table As DataTable = dv.Table

    Console.WriteLine(label)

    ' Loop through each row in the view.
    For Each rowView As DataRowView In dv
        sw = New System.IO.StringWriter

        ' Loop through each column.
        For Each col As DataColumn In table.Columns
            ' Output the value of each column's data.
            sw.Write(rowView(col.ColumnName).ToString() & ", ")
        Next
        output = sw.ToString
        ' Trim off the trailing ", ", so the output looks correct.
        If output.Length > 2 Then
            output = output.Substring(0, output.Length - 2)
        End If
        ' Display the row in the console window.
        Console.WriteLine(output)
    Next
    Console.WriteLine()
End Sub

Private Sub PrintTableOrView(ByVal table As DataTable, ByVal label As String)
    Dim sw As System.IO.StringWriter
    Dim output As String

    Console.WriteLine(label)

    ' Loop through each row in the table.
    For Each row As DataRow In table.Rows
        sw = New System.IO.StringWriter
        ' Loop through each column.
        For Each col As DataColumn In table.Columns
            ' Output the value of each column's data.
            sw.Write(row(col).ToString() & ", ")
        Next
        output = sw.ToString
        ' Trim off the trailing ", ", so the output looks correct.
        If output.Length > 2 Then
            output = output.Substring(0, output.Length - 2)
        End If
        ' Display the row in the console window.
        Console.WriteLine(output)
    Next
    Console.WriteLine()
End Sub

Im Beispiel wird der folgende Text im Konsolenfenster angezeigt:

Original table name: NewTable  
Current Values in Table  
1, Fruit, Apple, 14  
2, Fruit, Orange, 27  
3, Bread, Muffin, 23  
4, Fish, Salmon, 12  

Current Values in View  
2, Fruit, Orange, 27  
3, Bread, Muffin, 23  

Table created from filtered DataView  
2, Fruit, Orange, 27  
3, Bread, Muffin, 23  

New table name: FilteredTable

Hinweise

Da diese Methode ihnen nicht ermöglicht, eine Teilmenge verfügbarer Spalten anzugeben, enthält die Ausgabetabelle dieselben Spalten wie die Eingabetabelle.

Siehe auch

"DataSets", "DataTables" und "DataViews" (ADO.NET)

Gilt für

ToTable(String, Boolean, String[])

Erstellt eine neue DataTable basierend auf den Zeilen in einer vorhandenen DataView und gibt diese zurück.

public:
 System::Data::DataTable ^ ToTable(System::String ^ tableName, bool distinct, ... cli::array <System::String ^> ^ columnNames);

public System.Data.DataTable ToTable (string? tableName, bool distinct, params string[] columnNames);

public System.Data.DataTable ToTable (string tableName, bool distinct, params string[] columnNames);

member this.ToTable : string * bool * string[] -> System.Data.DataTable

Public Function ToTable (tableName As String, distinct As Boolean, ParamArray columnNames As String()) As DataTable

Parameter

tableName: String

Der Name der zurückgegebenen DataTable.

distinct: Boolean

Wenn auf true festgelegt, enthält die zurückgegebene DataTable Zeilen mit unterschiedlichen Werten für alle Spalten. Der Standardwert ist false.

columnNames: String[]

Ein Zeichenfolgenarray mit einer Liste der Spaltennamen, die in der zurückgegebenen DataTable enthalten sein sollen. Die DataTable enthält die angegebenen Spalten in der Reihenfolge, in der sie in diesem Array angezeigt werden.

Gibt zurück

DataTable

Eine neue DataTable-Instanz, die die angeforderten Zeilen und Spalten enthält.

Beispiele

Das folgende Konsolenanwendungsbeispiel erstellt eine DataTable, füllt die DataTable Daten aus, sortiert das DataViewUnd erstellt schließlich einen DataTable neuen Namen, der nur zwei Spalten enthält, beschränkt auf Zeilen, in denen alle Werte eindeutig sind.

private static void DemonstrateDataView()
{
    // Create a DataTable with three columns.
    DataTable table = new DataTable("NewTable");
    Console.WriteLine("Original table name: " + table.TableName);
    DataColumn column = new DataColumn("ID", typeof(System.Int32));
    table.Columns.Add(column);

    column = new DataColumn("Category", typeof(System.String));
    table.Columns.Add(column);

    column = new DataColumn("Product", typeof(System.String));
    table.Columns.Add(column);

    column = new DataColumn("QuantityInStock", typeof(System.Int32));
    table.Columns.Add(column);

    // Add some items.
    DataRow row = table.NewRow();
    row.ItemArray = new object[] { 1, "Fruit", "Apple", 14 };
    table.Rows.Add(row);

    row = table.NewRow();
    row.ItemArray = new object[] { 2, "Fruit", "Orange", 27 };
    table.Rows.Add(row);

    row = table.NewRow();
    row.ItemArray = new object[] { 3, "Bread", "Muffin", 23 };
    table.Rows.Add(row);

    row = table.NewRow();
    row.ItemArray = new object[] { 4, "Fish", "Salmon", 12 };
    table.Rows.Add(row);

    row = table.NewRow();
    row.ItemArray = new object[] { 5, "Fish", "Salmon", 15 };
    table.Rows.Add(row);

    row = table.NewRow();
    row.ItemArray = new object[] { 6, "Bread", "Croissant", 23};
    table.Rows.Add(row);

    // Mark all rows as "accepted". Not required
    // for this particular example.
    table.AcceptChanges();

    // Print current table values.
    PrintTableOrView(table, "Current Values in Table");

    DataView view = new DataView(table);
    view.Sort = "Category";
    PrintTableOrView(view, "Current Values in View");

    DataTable newTable = view.ToTable("UniqueData", true,
        "Category", "QuantityInStock");
    PrintTableOrView(newTable, "Table created from sorted DataView");
    Console.WriteLine("New table name: " + newTable.TableName);

    Console.WriteLine("Press any key to continue.");
    Console.ReadKey();
}

private static void PrintTableOrView(DataView dv, string label)
{
    System.IO.StringWriter sw;
    string output;
    DataTable table = dv.Table;

    Console.WriteLine(label);

    // Loop through each row in the view.
    foreach (DataRowView rowView in dv)
    {
        sw = new System.IO.StringWriter();

        // Loop through each column.
        foreach (DataColumn col in table.Columns)
        {
            // Output the value of each column's data.
            sw.Write(rowView[col.ColumnName].ToString() + ", ");
        }
        output = sw.ToString();
        // Trim off the trailing ", ", so the output looks correct.
        if (output.Length > 2)
        {
            output = output.Substring(0, output.Length - 2);
        }
        // Display the row in the console window.
        Console.WriteLine(output);
    }
    Console.WriteLine();
}

private static void PrintTableOrView(DataTable table, string label)
{
    System.IO.StringWriter sw;
    string output;

    Console.WriteLine(label);

    // Loop through each row in the table.
    foreach (DataRow row in table.Rows)
    {
        sw = new System.IO.StringWriter();
        // Loop through each column.
        foreach (DataColumn col in table.Columns)
        {
            // Output the value of each column's data.
            sw.Write(row[col].ToString() + ", ");
        }
        output = sw.ToString();
        // Trim off the trailing ", ", so the output looks correct.
        if (output.Length > 2)
        {
            output = output.Substring(0, output.Length - 2);
        }
        // Display the row in the console window.
        Console.WriteLine(output);
    } //
    Console.WriteLine();
}

Private Sub DemonstrateDataView()
    ' Create a DataTable with three columns.
    Dim table As New DataTable("NewTable")
    Console.WriteLine("Original table name: " & table.TableName)
    Dim column As New DataColumn("ID", GetType(System.Int32))
    table.Columns.Add(column)

    column = New DataColumn("Category", GetType(System.String))
    table.Columns.Add(column)

    column = New DataColumn("Product", GetType(System.String))
    table.Columns.Add(column)

    column = New DataColumn("QuantityInStock", GetType(System.Int32))
    table.Columns.Add(column)


    ' Add some items.
    Dim row As DataRow = table.NewRow()
    row.ItemArray = New Object() {1, "Fruit", "Apple", 14}
    table.Rows.Add(row)

    row = table.NewRow()
    row.ItemArray = New Object() {2, "Fruit", "Orange", 27}
    table.Rows.Add(row)

    row = table.NewRow()
    row.ItemArray = New Object() {3, "Bread", "Muffin", 23}
    table.Rows.Add(row)

    row = table.NewRow()
    row.ItemArray = New Object() {4, "Fish", "Salmon", 12}
    table.Rows.Add(row)

    row = table.NewRow()
    row.ItemArray = New Object() {5, "Fish", "Salmon", 15}
    table.Rows.Add(row)

    row = table.NewRow()
    row.ItemArray = New Object() {6, "Bread", "Croissant", 23}
    table.Rows.Add(row)

    ' Mark all rows as "accepted". Not required
    ' for this particular example.
    table.AcceptChanges()

    ' Print current table values.
    PrintTableOrView(table, "Current Values in Table")

    Dim view As New DataView(table)
    view.Sort = "Category"
    PrintTableOrView(view, "Current Values in View")

    Dim newTable As DataTable = view.ToTable("UniqueData", _
        True, "Category", "QuantityInStock")
    PrintTableOrView(newTable, "Table created from sorted DataView")
    Console.WriteLine("New table name: " & newTable.TableName)

    Console.WriteLine("Press any key to continue.")
    Console.ReadKey()
End Sub

Private Sub PrintTableOrView(ByVal dv As DataView, ByVal label As String)
    Dim sw As System.IO.StringWriter
    Dim output As String
    Dim table As DataTable = dv.Table

    Console.WriteLine(label)

    ' Loop through each row in the view.
    For Each rowView As DataRowView In dv
        sw = New System.IO.StringWriter

        ' Loop through each column.
        For Each col As DataColumn In table.Columns
            ' Output the value of each column's data.
            sw.Write(rowView(col.ColumnName).ToString() & ", ")
        Next
        output = sw.ToString
        ' Trim off the trailing ", ", so the output looks correct.
        If output.Length > 2 Then
            output = output.Substring(0, output.Length - 2)
        End If
        ' Display the row in the console window.
        Console.WriteLine(output)
    Next
    Console.WriteLine()
End Sub

Private Sub PrintTableOrView(ByVal table As DataTable, ByVal label As String)
    Dim sw As System.IO.StringWriter
    Dim output As String

    Console.WriteLine(label)

    ' Loop through each row in the table.
    For Each row As DataRow In table.Rows
        sw = New System.IO.StringWriter
        ' Loop through each column.
        For Each col As DataColumn In table.Columns
            ' Output the value of each column's data.
            sw.Write(row(col).ToString() & ", ")
        Next
        output = sw.ToString
        ' Trim off the trailing ", ", so the output looks correct.
        If output.Length > 2 Then
            output = output.Substring(0, output.Length - 2)
        End If
        ' Display the row in the console window.
        Console.WriteLine(output)
    Next
    Console.WriteLine()
End Sub

Im Beispiel wird die folgende Ausgabe im Konsolenfenster angezeigt:

Original table name: NewTable  
Current Values in Table  
1, Fruit, Apple, 14  
2, Fruit, Orange, 27  
3, Bread, Muffin, 23  
4, Fish, Salmon, 12  
5, Fish, Salmon, 15  
6, Bread, Croissant, 23  

Current Values in View  
3, Bread, Muffin, 23  
6, Bread, Croissant, 23  
4, Fish, Salmon, 12  
5, Fish, Salmon, 15  
1, Fruit, Apple, 14  
2, Fruit, Orange, 27  

Table created from sorted DataView  
Bread, 23  
Fish, 12  
Fish, 15  
Fruit, 14  
Fruit, 27  

New table name: UniqueData

Hinweise

Verwenden Sie diese überladene Version der ToTable Methode, wenn Sie unterschiedliche Werte in einer Teilmenge verfügbarer Spalten abrufen müssen, indem Sie einen neuen Namen für den zurückgegebenen DataTableWert angeben. Wenn Sie keine unterschiedlichen Zeilen oder eine Teilmenge von Spalten benötigen, lesen Sie .ToTable

Siehe auch

"DataSets", "DataTables" und "DataViews" (ADO.NET)

Gilt für

ToTable()

Erstellt eine neue DataTable basierend auf den Zeilen in einer vorhandenen DataView und gibt diese zurück.

public:
 System::Data::DataTable ^ ToTable();

public System.Data.DataTable ToTable ();

member this.ToTable : unit -> System.Data.DataTable

Public Function ToTable () As DataTable

Gibt zurück

DataTable

Eine neue DataTable-Instanz, die die angeforderten Zeilen und Spalten enthält.

Beispiele

Das folgende Konsolenanwendungsbeispiel erstellt eine DataTable, füllt die DataTable Daten aus, erstellt eine gefilterte Ansicht basierend auf den ursprünglichen Daten und erstellt schließlich eine DataTable , die die gefilterten Zeilen enthält.

using System;
using System.Data;

class Program {
    static void Main() {
        DemonstrateDataView();
    }

    private static void DemonstrateDataView() {
        // Create a DataTable with three columns.
        DataTable table = new DataTable("NewTable");
        Console.WriteLine("Original table name: " + table.TableName);
        DataColumn column = new DataColumn("ID", typeof(System.Int32));
        table.Columns.Add(column);

        column = new DataColumn("Category", typeof(System.String));
        table.Columns.Add(column);

        column = new DataColumn("Product", typeof(System.String));
        table.Columns.Add(column);

        column = new DataColumn("QuantityInStock", typeof(System.Int32));
        table.Columns.Add(column);

        // Add some items.
        DataRow row = table.NewRow();
        row.ItemArray = new object[] { 1, "Fruit", "Apple", 14 };
        table.Rows.Add(row);

        row = table.NewRow();
        row.ItemArray = new object[] { 2, "Fruit", "Orange", 27 };
        table.Rows.Add(row);

        row = table.NewRow();
        row.ItemArray = new object[] { 3, "Bread", "Muffin", 23 };
        table.Rows.Add(row);

        row = table.NewRow();
        row.ItemArray = new object[] { 4, "Fish", "Salmon", 12 };
        table.Rows.Add(row);

        // Mark all rows as "accepted". Not really required
        // for this particular example.
        table.AcceptChanges();

        // Print current table values.
        PrintTableOrView(table, "Current Values in Table");

        DataView view = new DataView(table);
        view.RowFilter = "QuantityInStock > 15";
        PrintTableOrView(view, "Current Values in View");

        DataTable newTable = view.ToTable();
        PrintTableOrView(newTable, "Table created from filtered DataView");
        Console.WriteLine("New table name: " + newTable.TableName);

        Console.WriteLine("Press any key to continue.");
        Console.ReadKey();
    }

    private static void PrintTableOrView(DataView dv, string label) {
        System.IO.StringWriter sw;
        string output;
        DataTable table = dv.Table;

        Console.WriteLine(label);

        // Loop through each row in the view.
        foreach (DataRowView rowView in dv) {
            sw = new System.IO.StringWriter();

            // Loop through each column.
            foreach (DataColumn col in table.Columns) {
                // Output the value of each column's data.
                sw.Write(rowView[col.ColumnName].ToString() + ", ");
            }

            output = sw.ToString();

            // Trim off the trailing ", ", so the output looks correct.
            if (output.Length > 2)
                output = output.Substring(0, output.Length - 2);

            // Display the row in the console window.
            Console.WriteLine(output);
        }
        Console.WriteLine();
    }

    private static void PrintTableOrView(DataTable table, string label) {
        System.IO.StringWriter sw;
        string output;

        Console.WriteLine(label);

        // Loop through each row in the table.
        foreach (DataRow row in table.Rows) {
            sw = new System.IO.StringWriter();

            // Loop through each column.
            foreach (DataColumn col in table.Columns) {
                // Output the value of each column's data.
                sw.Write(row[col].ToString() + ", ");
            }

            output = sw.ToString();

            // Trim off the trailing ", ", so the output looks correct.
            if (output.Length > 2)
                output = output.Substring(0, output.Length - 2);

            // Display the row in the console window.
            Console.WriteLine(output);
        }
        Console.WriteLine();
    }
}

Private Sub DemonstrateDataView()
    ' Create a DataTable with three columns.
    Dim table As New DataTable("NewTable")
    Console.WriteLine("Original table name: " & table.TableName)
    Dim column As New DataColumn("ID", GetType(System.Int32))
    table.Columns.Add(column)

    column = New DataColumn("Category", GetType(System.String))
    table.Columns.Add(column)

    column = New DataColumn("Product", GetType(System.String))
    table.Columns.Add(column)

    column = New DataColumn("QuantityInStock", GetType(System.Int32))
    table.Columns.Add(column)

    ' Add some items.
    Dim row As DataRow = table.NewRow()
    row.ItemArray = New Object() {1, "Fruit", "Apple", 14}
    table.Rows.Add(row)

    row = table.NewRow()
    row.ItemArray = New Object() {2, "Fruit", "Orange", 27}
    table.Rows.Add(row)

    row = table.NewRow()
    row.ItemArray = New Object() {3, "Bread", "Muffin", 23}
    table.Rows.Add(row)

    row = table.NewRow()
    row.ItemArray = New Object() {4, "Fish", "Salmon", 12}
    table.Rows.Add(row)

    ' Mark all rows as "accepted". Not required
    ' for this particular example.
    table.AcceptChanges()

    ' Print current table values.
    PrintTableOrView(table, "Current Values in Table")

    Dim view As New DataView(table)
    view.RowFilter = "QuantityInStock > 15"
    PrintTableOrView(view, "Current Values in View")

    Dim newTable As DataTable = view.ToTable()
    PrintTableOrView(newTable, "Table created from filtered DataView")
    Console.WriteLine("New table name: " & newTable.TableName)

    Console.WriteLine("Press any key to continue.")
    Console.ReadKey()
End Sub

Private Sub PrintTableOrView(ByVal dv As DataView, ByVal label As String)
    Dim sw As System.IO.StringWriter
    Dim output As String
    Dim table As DataTable = dv.Table

    Console.WriteLine(label)

    ' Loop through each row in the view.
    For Each rowView As DataRowView In dv
        sw = New System.IO.StringWriter

        ' Loop through each column.
        For Each col As DataColumn In table.Columns
            ' Output the value of each column's data.
            sw.Write(rowView(col.ColumnName).ToString() & ", ")
        Next
        output = sw.ToString
        ' Trim off the trailing ", ", so the output looks correct.
        If output.Length > 2 Then
            output = output.Substring(0, output.Length - 2)
        End If
        ' Display the row in the console window.
        Console.WriteLine(output)
    Next
    Console.WriteLine()
End Sub

Private Sub PrintTableOrView(ByVal table As DataTable, ByVal label As String)
    Dim sw As System.IO.StringWriter
    Dim output As String

    Console.WriteLine(label)

    ' Loop through each row in the table.
    For Each row As DataRow In table.Rows
        sw = New System.IO.StringWriter
        ' Loop through each column.
        For Each col As DataColumn In table.Columns
            ' Output the value of each column's data.
            sw.Write(row(col).ToString() & ", ")
        Next
        output = sw.ToString
        ' Trim off the trailing ", ", so the output looks correct.
        If output.Length > 2 Then
            output = output.Substring(0, output.Length - 2)
        End If
        ' Display the row in the console window.
        Console.WriteLine(output)
    Next
    Console.WriteLine()
End Sub

Im Beispiel wird der folgende Text im Konsolenfenster angezeigt:

Original table name: NewTable  
Current Values in Table  
1, Fruit, Apple, 14  
2, Fruit, Orange, 27  
3, Bread, Muffin, 23  
4, Fish, Salmon, 12  

Current Values in View  
2, Fruit, Orange, 27  
3, Bread, Muffin, 23  

Table created from filtered DataView  
2, Fruit, Orange, 27  
3, Bread, Muffin, 23  

New table name: NewTable

Hinweise

Da diese Methode den Namen für die Ausgabe DataTablenicht angeben lässt, entspricht der Name der Quelle dem Namen der Quelle DataTable. Da diese Methode ihnen nicht ermöglicht, eine Teilmenge verfügbarer Spalten anzugeben, enthält die Ausgabetabelle dieselben Spalten wie die Eingabetabelle.

Siehe auch

"DataSets", "DataTables" und "DataViews" (ADO.NET)

Gilt für

DataView.ToTable Methode

Definition

Überlädt

Hinweise

ToTable(Boolean, String[])

Parameter

Gibt zurück

Beispiele

Hinweise

Gilt für

ToTable(String)

Parameter

Gibt zurück

Beispiele

Hinweise

Siehe auch

Gilt für

ToTable(String, Boolean, String[])

Parameter

Gibt zurück

Beispiele

Hinweise

Siehe auch

Gilt für

ToTable()

Gibt zurück

Beispiele

Hinweise

Siehe auch

Gilt für

Zusätzliche Ressourcen