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DataTable.ColumnChanged Event

Definition

Occurs after a value has been changed for the specified DataColumn in a DataRow.

C#
public event System.Data.DataColumnChangeEventHandler? ColumnChanged;
C#
public event System.Data.DataColumnChangeEventHandler ColumnChanged;
C#
[System.Data.DataSysDescription("DataTableColumnChangedDescr")]
public event System.Data.DataColumnChangeEventHandler ColumnChanged;

Event Type

Attributes

Examples

C#
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]);
}

Remarks

For more information, see Handling DataTable Events.

Applies to

Продукт Версии
.NET Core 2.0, Core 2.1, Core 2.2, Core 3.0, Core 3.1, 5, 6, 7, 8, 9, 10
.NET Framework 1.1, 2.0, 3.0, 3.5, 4.0, 4.5, 4.5.1, 4.5.2, 4.6, 4.6.1, 4.6.2, 4.7, 4.7.1, 4.7.2, 4.8, 4.8.1
.NET Standard 2.0, 2.1

See also