The DataTable object contains the schema and data
for a single table. Column settings, such as column names and data
types are specified using the DataColumn objects
contained in the table and accessed using the
Columns property. Each row of data is encapsulated
within a separate DataRow object, which is
accessed using the Rows property. Also,
ForeignKeyConstraint and
UniqueConstraint objects can be added to the
ConstraintCollection for the table, which is
accessed using the Constraints property.
The DataTable provides many of the same methods as
the DataSet . For example, you can use
Copy( ) , Clone( ) ,
Clear( ) , GetChanges( ) ,
HasErrors , and AcceptChanges(
) in the same way as described for the
DataSet . In addition, you can use the
Select( ) method to retrieve an array of
DataRow objects that match a specified SQL filter
expression. There are four overloaded versions of the
Select( ) method, some of which allow you to
specify a sort order and filter based on the
DataRowState of the DataRow .
Finally, you can use the NewRow( ) method to
generate a new DataRow object that has the same
schema as the DataTable . This is detached row;
once you have finished entering the required information you must add
it to the RowCollection .
The DataTable has six events that allow you to
react when column values are changed. You can handle
RowChanging to implement row-specific validation
rules or handle ColumnChanging to implement
column-specific validation rules. Both events fire during the course
of a column edit; the difference is that
ColumnChanging provides a reference to a
DataColumn object. RowChanged ,
ColumnChanged , and RowDeleted
occur after a change has been applied. They are most useful if you
need to log the change or update part of the user interface.
public class DataTable : System.ComponentModel.MarshalByValueComponent ,
System.ComponentModel.IListSource, System.ComponentModel.ISupportInitialize,
System.Runtime.Serialization.ISerializable {
// Public Constructors
public DataTable( );
public DataTable( string tableName);
// Protected Constructors
protected DataTable(
System.Runtime.Serialization.SerializationInfo info,
System.Runtime.Serialization.StreamingContext context);
// Public Instance Properties
public bool CaseSensitive{set; get; }
public DataRelationCollection ChildRelations{get; }
public DataColumnCollection Columns{get; }
public ConstraintCollection Constraints{get; }
public DataSet DataSet{get; }
public DataView DefaultView{get; }
public string DisplayExpression{set; get; }
public PropertyCollection ExtendedProperties{get; }
public bool HasErrors{get; }
public CultureInfo Locale{set; get; }
public int MinimumCapacity{set; get; }
public string Namespace{set; get; }
public DataRelationCollection ParentRelations{get; }
public string Prefix{set; get; }
public DataColumn[ ] PrimaryKey{set; get; }
public DataRowCollection Rows{get; }
public override ISite Site{set; get; } // overrides System.ComponentModel.MarshalByValueComponent
public string TableName{set; get; }
// Public Instance Methods
public void AcceptChanges( );
public void BeginInit( ); // implements System.ComponentModel.ISupportInitialize
public void BeginLoadData( );
public void Clear( );
public virtual DataTable Clone( );
public object Compute( string expression, string filter);
public DataTable Copy( );
public void EndInit( ); // implements System.ComponentModel.ISupportInitialize
public void EndLoadData( );
public DataTable GetChanges( );
public DataTable GetChanges( DataRowState rowStates);
public DataRow[ ] GetErrors( );
public void ImportRow( DataRow row);
public DataRow LoadDataRow(object[ ] values, bool fAcceptChanges);
public DataRow NewRow( );
public void RejectChanges( );
public virtual void Reset( );
public DataRow[ ] Select( );
public DataRow[ ] Select( string filterExpression);
public DataRow[ ] Select(string filterExpression, string sort);
public DataRow[ ] Select(string filterExpression, string sort, DataViewRowState recordStates);
public override string ToString( ); // overrides System.ComponentModel.MarshalByValueComponent
// Protected Instance Methods
protected virtual DataTable CreateInstance( );
protected virtual Type GetRowType( );
protected internal DataRow[ ] NewRowArray( int size);
protected virtual DataRow NewRowFromBuilder(DataRowBuilder builder);
protected virtual void OnColumnChanged(
DataColumnChangeEventArgs e);
protected virtual void OnColumnChanging(DataColumnChangeEventArgs e);
protected internal virtual void OnPropertyChanging(System.ComponentModel.PropertyChangedEventArgs pcevent);
protected internal virtual void OnRemoveColumn(DataColumn column);
protected virtual void OnRowChanged(DataRowChangeEventArgs e);
protected virtual void OnRowChanging(DataRowChangeEventArgs e);
protected virtual void OnRowDeleted(DataRowChangeEventArgs e);
protected virtual void OnRowDeleting(DataRowChangeEventArgs e);
// Events
public event DataColumnChangeEventHandler ColumnChanged;
public event DataColumnChangeEventHandler ColumnChanging;
public event DataRowChangeEventHandler RowChanged;
public event DataRowChangeEventHandler RowChanging;
public event DataRowChangeEventHandler RowDeleted;
public event DataRowChangeEventHandler RowDeleting;
}
System.ComponentModel.MarshalByValueComponent(System.ComponentModel.IComponent, System.IDisposable
, System.IServiceProvider)