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You use an object of the DataTable class to represent a table. You can also store multiple DataTable objects in a DataSet. Table 11.1 shows some of the DataTable properties.
PROPERTY | TYPE | DESCRIPTION |
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CaseSensitive | bool | Gets or sets a bool value that indicates whether string comparisons within DataTable objects are case-sensitive. |
ChildRelations | DataRelationCollection | Gets the collection of relations (DataRelationCollection) that allows navigation from a parent table to a child table. A DataRelationCollection consists of DataRelation objects. |
Columns | DataColumnCollection | Gets the collection of columns (DataColumnCollection) that contains DataColumn objects that represent the columns in the DataTable object. |
Constraints | ConstraintCollection | Gets the collection of constraints (ConstraintCollection) that contains Constraint objects that represent primary key (UniqueConstraint) or foreign key constraints (ForeignKeyConstraint) in the DataTable object. |
DataSet | DataSet | Gets the DataSet to which the DataTable belongs. |
HasErrors | bool | Returns a bool value that indicates whether any of the rows in the DataTable have errors. |
PrimaryKey | DataColumn[] | Gets or sets an array of DataColumn objects that are the primary keys for the DataTable. |
Rows | DataRowCollection | Gets the collection of rows (DataRowCollection) that contains the DataRow objects stored in the DataTable. |
TableName | string | Gets or sets the name of the DataTable object. |
Table 11.2 shows some of the DataTable methods.
METHOD | RETURN TYPE | DESCRIPTION |
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AcceptChanges() | void | Commits all the changes made to the DataTable object since it was loaded or since the last time the AcceptChanges() method was called. |
Clear() | void | Removes all rows from the DataTable object. |
Clone() | DataTable | Clones the structure of the DataTable object and returns that clone. |
Compute() | object | Computes the given expression on the current rows that pass the filter criteria. |
GetChanges() | DataTable | Overloaded. Returns a copy of the DataTable object since it was last loaded or since the last time the AcceptChanges() method was called. |
GetErrors() | DataRow[] | Overloaded. Gets a copy of all the DataRow objects that have errors. |
LoadDataRow() | DataRow | Finds and updates a specified DataRow object. If no matching object is found, a new row is created using the specified values. |
NewRow() | DataRow | Creates a new DataRow object in the DataTable. |
RejectChanges() | void | Undoes all the changes made to the DataTable object since it was created or since the last time the AcceptChanges() method was called. |
Select() | DataRow[] | Overloaded. Returns the array of DataRow objects stored in the DataTable that match the specified filter string. You can also pass a string containing details on how to sort the DataRow objects. |
Table 11.3 shows some of the DataTable events.
EVENT | EVENT HANDLER | DESCRIPTION |
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ColumnChanging | DataColumnChangeEventHandler | Fires before a changed DataColumn value is committed in a DataRow. |
ColumnChanged | DataColumnChangeEventHandler | Fires after a changed DataColumn value is committed in a DataRow. |
RowChanging | DataRowChangeEventHandler | Fires before a changed DataRow is committed in a DataTable. |
RowChanged | DataRowChangeEventHandler | Fires after a changed DataRow is committed in a DataTable. |
RowDeleting | DataRowChangeEventHandler | Fires before a DataRow is deleted from a DataTable. |
RowDeleted | DataRowChangeEventHandler | Fires after a DataRow is deleted from a DataTable. |
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