DataTable.ColumnChanging Event

Definition

Namespace:

System.Data

Assemblies:

netstandard.dll, System.Data.Common.dll

Source:

DataTable.cs

Occurs when a value is being changed for the specified DataColumn in a DataRow.

C#

public event System.Data.DataColumnChangeEventHandler? ColumnChanging;

Event Type

DataColumnChangeEventHandler

Examples

C#

private static void DataTableColumnChanging()
{
    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 ColumnChanging event handler for the table.
    custTable.ColumnChanging += new
        DataColumnChangeEventHandler(Column_Changing );

    // 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_Changing(object sender,
    DataColumnChangeEventArgs e )
{
    Console.WriteLine(
        "Column_Changing Event: name={0}; Column={1}; proposed name={2}",
        e.Row["name"], e.Column.ColumnName, e.ProposedValue );
}

Remarks

For more information, see Handling DataTable Events.

Applies to

See also

• DataTables