Namespace:
System.Data
Assembly:
System.Data (in System.Data.dll)
Visual Basic (Declaration)
Public Event ColumnChanged As DataColumnChangeEventHandler
Dim instance As DataTable
Dim handler As DataColumnChangeEventHandler
AddHandler instance.ColumnChanged, handler
public event DataColumnChangeEventHandler ColumnChanged
public:
event DataColumnChangeEventHandler^ ColumnChanged {
void add (DataColumnChangeEventHandler^ value);
void remove (DataColumnChangeEventHandler^ value);
}
JScript does not support events.
For more information, see Handling DataTable Events (ADO.NET).
Private Shared Sub DataTableColumnChanged()
Dim custTable As DataTable = New DataTable("Customers")
' add columns
custTable.Columns.Add("id", Type.GetType("System.Int32"))
custTable.Columns.Add("name", Type.GetType("System.String"))
custTable.Columns.Add("address", Type.GetType("System.String"))
' set PrimaryKey
custTable.Columns("id").Unique = true
custTable.PrimaryKey = New DataColumn() { custTable.Columns("id") }
' add a ColumnChanged event handler for the table.
AddHandler custTable.ColumnChanged, _
New DataColumnChangeEventHandler(AddressOf Column_Changed )
' add ten rows
Dim id As Integer
For id = 1 To 10
custTable.Rows.Add( _
New Object() { id, string.Format("customer{0}", id), _
string.Format("address{0}", id) })
Next
custTable.AcceptChanges()
' change the name column in all the rows
Dim row As DataRow
For Each row In custTable.Rows
row("name") = string.Format("vip{0}", row("id"))
Next
End Sub
Private Shared Sub Column_Changed(sender As Object, _
e As DataColumnChangeEventArgs)
Console.WriteLine("Column_Changed Event: name={0}; Column={1}; original name={2}", _
e.Row("name"), e.Column.ColumnName, e.Row("name", DataRowVersion.Original))
End Sub
private static void DataTableColumnChanged()
{
DataTable custTable = new DataTable("Customers");
// add columns
custTable.Columns.Add("id", typeof(int));
custTable.Columns.Add("name", typeof(string));
custTable.Columns.Add("address", typeof(string));
// set PrimaryKey
custTable.Columns["id"].Unique = true;
custTable.PrimaryKey = new DataColumn[] { custTable.Columns["id"] };
// add a ColumnChanged event handler for the table.
custTable.ColumnChanged += new
DataColumnChangeEventHandler(Column_Changed );
// add ten rows
for(int id=1; id<=10; id++)
{
custTable.Rows.Add(
new object[] { id, string.Format("customer{0}", id),
string.Format("address{0}", id) });
}
custTable.AcceptChanges();
// change the name column in all the rows
foreach(DataRow row in custTable.Rows )
{
row["name"] = string.Format("vip{0}", row["id"]);
}
}
private static void Column_Changed(object sender, DataColumnChangeEventArgs e )
{
Console.WriteLine("Column_Changed Event: name={0}; Column={1}; original name={2}",
e.Row["name"], e.Column.ColumnName, e.Row["name", DataRowVersion.Original]);
}
Windows 7, Windows Vista, Windows XP SP2, Windows XP Media Center Edition, Windows XP Professional x64 Edition, Windows XP Starter Edition, Windows Server 2008 R2, Windows Server 2008, Windows Server 2003, Windows Server 2000 SP4, Windows Millennium Edition, Windows 98, Windows CE, Windows Mobile for Smartphone, Windows Mobile for Pocket PC, Xbox 360, Zune
The .NET Framework and .NET Compact Framework do not support all versions of every platform. For a list of the supported versions, see .NET Framework System Requirements.
.NET Framework
Supported in: 3.5, 3.0, 2.0, 1.1, 1.0
.NET Compact Framework
Supported in: 3.5, 2.0, 1.0
XNA Framework
Supported in: 3.0, 2.0, 1.0
Reference
Other Resources