DataView.ToTable Método
Definição
Importante
Algumas informações dizem respeito a um produto pré-lançado que pode ser substancialmente modificado antes de ser lançado. A Microsoft não faz garantias, de forma expressa ou implícita, em relação à informação aqui apresentada.
Sobrecargas
| Name | Description |
|---|---|
| ToTable(Boolean, String[]) |
Cria e devolve um novo DataTable com base em linhas num .DataView |
| ToTable(String) |
Cria e devolve um novo DataTable com base em linhas num .DataView |
| ToTable(String, Boolean, String[]) |
Cria e devolve um novo DataTable com base em linhas num .DataView |
| ToTable() |
Cria e devolve um novo DataTable com base em linhas num .DataView |
Observações
O retorno DataTable mantém os valores das seguintes propriedades da fonte DataTable: Namespace, Prefix, Locale, e CaseSensitive. Cada coluna no resultado DataTable contém uma cópia idêntica de todas as propriedades correspondentes no subjacente DataTable.
As DataRow instâncias no devolvido DataTable conterão valores consistentes com a semântica CLR. Ou seja, para todos os tipos de dados exceto os definidos pelo utilizador, os valores correspondentes das colunas são copiados por valor. Para tipos de dados definidos pelo utilizador, os dados da coluna são copiados por referência.
ToTable(Boolean, String[])
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
Parâmetros
- distinct
- Boolean
Se true, o retornado DataTable contém linhas que têm valores distintos para todas as suas colunas. O valor predefinido é false.
- columnNames
- String[]
Um array de strings que contém uma lista dos nomes das colunas a serem incluídos no .DataTable O DataTable contém as colunas especificadas na ordem em que aparecem dentro deste array.
Devoluções
Uma nova DataTable instância que contém as linhas e colunas solicitadas.
Exemplos
O exemplo seguinte de aplicação de consola cria um DataTable, preenche o DataTable com dados, ordena o DataView, e finalmente cria um DataTable com apenas duas colunas, limitadas a linhas em que todos os valores são únicos.
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
O exemplo exibe a seguinte saída na janela do console:
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
Observações
Como este método não permite especificar o nome da saída DataTable, o seu nome é o mesmo que o nome da fonte DataTable.
Aplica-se a
ToTable(String)
public:
System::Data::DataTable ^ ToTable(System::String ^ tableName);
public System.Data.DataTable ToTable(string tableName);
member this.ToTable : string -> System.Data.DataTable
Public Function ToTable (tableName As String) As DataTable
Parâmetros
Devoluções
Uma nova DataTable instância que contém as linhas e colunas solicitadas.
Exemplos
O seguinte exemplo de aplicação de consola cria um DataTable, preenche o DataTable com dados, cria uma vista filtrada baseada nos dados originais e, finalmente, cria um DataTable com um novo nome que contém as linhas filtradas.
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
O exemplo mostra o seguinte texto na janela da consola:
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
Observações
Como este método não permite especificar um subconjunto de colunas disponíveis, a tabela de saída contém as mesmas colunas da tabela de entrada.
Ver também
Aplica-se a
ToTable(String, Boolean, String[])
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);
member this.ToTable : string * bool * string[] -> System.Data.DataTable
Public Function ToTable (tableName As String, distinct As Boolean, ParamArray columnNames As String()) As DataTable
Parâmetros
- distinct
- Boolean
Se true, o retornado DataTable contém linhas que têm valores distintos para todas as suas colunas. O valor predefinido é false.
- columnNames
- String[]
Um array de strings que contém uma lista dos nomes das colunas a serem incluídos no .DataTable O DataTable contém as colunas especificadas na ordem em que aparecem dentro deste array.
Devoluções
Uma nova DataTable instância que contém as linhas e colunas solicitadas.
Exemplos
O seguinte exemplo de aplicação de consola cria um DataTable, preenche o DataTable com dados, ordena o DataView, e finalmente cria um DataTable com um novo nome que contém apenas duas colunas, limitadas a linhas em que todos os valores são únicos.
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
O exemplo exibe a seguinte saída na janela do console:
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
Observações
Use esta versão sobrecarregada do ToTable método se tiver de recuperar valores distintos num subconjunto de colunas disponíveis, especificando um novo nome para o .DataTable Se não precisar de linhas distintas ou de um subconjunto de colunas, veja ToTable.
Ver também
Aplica-se a
ToTable()
public:
System::Data::DataTable ^ ToTable();
public System.Data.DataTable ToTable();
member this.ToTable : unit -> System.Data.DataTable
Public Function ToTable () As DataTable
Devoluções
Uma nova DataTable instância que contém as linhas e colunas solicitadas.
Exemplos
O seguinte exemplo de aplicação de consola cria um DataTable, preenche o DataTable com dados, cria uma vista filtrada baseada nos dados originais e, finalmente, cria um DataTable que contém as linhas filtradas.
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
O exemplo mostra o seguinte texto na janela da consola:
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
Observações
Como este método não permite especificar o nome da saída DataTable, o seu nome é o mesmo que o nome da fonte DataTable. Como este método não permite especificar um subconjunto de colunas disponíveis, a tabela de saída contém as mesmas colunas da tabela de entrada.