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DataTableCollection.Remove Method

Definition

Removes a specified DataTable object from the collection.

Overloads

Remove(String, String)

Removes the DataTable object with the specified name from the collection.

Remove(DataTable)

Removes the specified DataTable object from the collection.

Remove(String)

Removes the DataTable object with the specified name from the collection.

Remove(String, String)

Source:
DataTableCollection.cs
Source:
DataTableCollection.cs
Source:
DataTableCollection.cs

Removes the DataTable object with the specified name from the collection.

public:
 void Remove(System::String ^ name, System::String ^ tableNamespace);
public void Remove (string name, string tableNamespace);
member this.Remove : string * string -> unit
Public Sub Remove (name As String, tableNamespace As String)

Parameters

name
String

The name of the DataTable object to remove.

tableNamespace
String

The name of the DataTable namespace to look in.

Exceptions

The collection does not have a table with the specified name.

Examples

The following example uses the Contains and CanRemove methods to test whether a named table exists and can be removed. If so, the Remove method is called to remove the table.

private void RemoveTables()
{
    // Set the name of the table to test for and remove.
    string name = "Suppliers";

    // Presuming a DataGrid is displaying more than one table, get its DataSet.
    DataSet thisDataSet = (DataSet)DataGrid1.DataSource;
    DataTableCollection tablesCol = thisDataSet.Tables;
    if (tablesCol.Contains(name) && tablesCol.CanRemove(tablesCol[name]))
        tablesCol.Remove(name);
}
Private Sub RemoveTables()
   ' Set the name of the table to test for and remove.
   Dim name As String = "Suppliers"

   ' Presuming a DataGrid is displaying more than one table, get its DataSet.
   Dim thisDataSet As DataSet = CType(DataGrid1.DataSource, DataSet)
   Dim tablesCol As DataTableCollection = thisDataSet.Tables
   If tablesCol.Contains(name) _
   And tablesCol.CanRemove(tablesCol(name)) Then 
      tablesCol.Remove(name)
   End If
End Sub

Remarks

The CollectionChanged event occurs when a table is successfully removed.

To determine whether a given table exists and can be removed before invoking Remove, use the Contains and the CanRemove methods.

See also

Applies to

Remove(DataTable)

Source:
DataTableCollection.cs
Source:
DataTableCollection.cs
Source:
DataTableCollection.cs

Removes the specified DataTable object from the collection.

public:
 void Remove(System::Data::DataTable ^ table);
public void Remove (System.Data.DataTable table);
member this.Remove : System.Data.DataTable -> unit
Public Sub Remove (table As DataTable)

Parameters

table
DataTable

The DataTable to remove.

Exceptions

The value specified for the table is null.

The table does not belong to this collection.

-or-

The table is part of a relationship.

Examples

The following example uses the CanRemove method to test whether each table can be removed from a DataSet. If so, the Remove method is called to remove the table.

public static void DataTableCollectionCanRemove()
{
    // create a DataSet with two tables
    DataSet dataSet = new DataSet();

    // create Customer table
    DataTable customersTable = new DataTable("Customers");
    customersTable.Columns.Add("customerId",
        typeof(int) ).AutoIncrement = true;
    customersTable.Columns.Add("name",
        typeof(string));
    customersTable.PrimaryKey = new DataColumn[]
        { customersTable.Columns["customerId"] };

    // create Orders table
    DataTable ordersTable = new DataTable("Orders");
    ordersTable.Columns.Add("orderId",
        typeof(int) ).AutoIncrement = true;
    ordersTable.Columns.Add("customerId",
        typeof(int) );
    ordersTable.Columns.Add("amount",
        typeof(double));
    ordersTable.PrimaryKey = new DataColumn[]
        { ordersTable.Columns["orderId"] };

    dataSet.Tables.AddRange(new DataTable[]
        {customersTable, ordersTable });

    // remove all tables
    // check if table can be removed and then
    // remove it, cannot use a foreach when
    // removing items from a collection
    while(dataSet.Tables.Count > 0)
    {
        DataTable table = dataSet.Tables[0];
        if(dataSet.Tables.CanRemove(table))
        {
            dataSet.Tables.Remove(table);
        }
    }

    Console.WriteLine("dataSet has {0} tables",
        dataSet.Tables.Count);
}
Public Sub Main
DataTableCollectionCanRemove
End Sub

Public Sub DataTableCollectionCanRemove()
    ' create a DataSet with two tables
    Dim dataSet As New DataSet()

    ' create Customer table
    Dim customersTable As New DataTable("Customers")
    customersTable.Columns.Add("customerId", _
        System.Type.GetType("System.Integer")).AutoIncrement = True
    customersTable.Columns.Add("name", _
        System.Type.GetType("System.String"))
    customersTable.PrimaryKey = New DataColumn() _
        {customersTable.Columns("customerId")}

    ' create Orders table
    Dim ordersTable As New DataTable("Orders")
    ordersTable.Columns.Add("orderId", _
        System.Type.GetType("System.Integer")).AutoIncrement = True
    ordersTable.Columns.Add("customerId", _
        System.Type.GetType("System.Integer"))
    ordersTable.Columns.Add("amount", _
        System.Type.GetType("System.Double"))
    ordersTable.PrimaryKey = New DataColumn() _
        {ordersTable.Columns("orderId")}

    dataSet.Tables.AddRange(New DataTable() {customersTable, ordersTable})

    ' remove all tables
    ' check if table can be removed and then
    ' remove it, cannot use a foreach when
    ' removing items from a collection
    Do While (dataSet.Tables.Count > 0)
        Dim table As DataTable = dataSet.Tables(0)
        If (dataSet.Tables.CanRemove(table)) Then
            dataSet.Tables.Remove(table)
        End If
    Loop

Console.WriteLine("dataSet has {0} tables", dataSet.Tables.Count)
End Sub

Remarks

The CollectionChanged event occurs when a table is successfully removed.

To determine whether a given table exists and can be removed before invoking Remove, use the Contains and the CanRemove methods.

See also

Applies to

Remove(String)

Source:
DataTableCollection.cs
Source:
DataTableCollection.cs
Source:
DataTableCollection.cs

Removes the DataTable object with the specified name from the collection.

public:
 void Remove(System::String ^ name);
public void Remove (string name);
member this.Remove : string -> unit
Public Sub Remove (name As String)

Parameters

name
String

The name of the DataTable object to remove.

Exceptions

The collection does not have a table with the specified name.

Examples

The following example uses the Contains and CanRemove methods to test whether a named table exists and can be removed. If so, the Remove method is called to remove the table.

private void RemoveTables()
{
    // Set the name of the table to test for and remove.
    string name = "Suppliers";

    // Presuming a DataGrid is displaying more than one table, get its DataSet.
    DataSet thisDataSet = (DataSet)DataGrid1.DataSource;
    DataTableCollection tablesCol = thisDataSet.Tables;
    if (tablesCol.Contains(name) && tablesCol.CanRemove(tablesCol[name]))
        tablesCol.Remove(name);
}
Private Sub RemoveTables()
   ' Set the name of the table to test for and remove.
   Dim name As String = "Suppliers"

   ' Presuming a DataGrid is displaying more than one table, get its DataSet.
   Dim thisDataSet As DataSet = CType(DataGrid1.DataSource, DataSet)
   Dim tablesCol As DataTableCollection = thisDataSet.Tables
   If tablesCol.Contains(name) _
   And tablesCol.CanRemove(tablesCol(name)) Then 
      tablesCol.Remove(name)
   End If
End Sub

Remarks

The CollectionChanged event occurs when a table is successfully removed.

To determine whether a given table exists and can be removed before invoking Remove, use the Contains and the CanRemove methods.

See also

Applies to