Cursor class abstract
represents a cursor for traversing or iterating over multiple records in a database.
The cursor has a source that indicates which index or object store it is iterating over. It has a position within the range, and moves in a direction that is increasing or decreasing in the order of record keys. The cursor enables an application to asynchronously process all the records in the cursor's range.
You can have an unlimited number of cursors at the same time. You always get the same IDBCursor object representing a given cursor. Operations are performed on the underlying index or object store.
- Implementers
Constructors
- Cursor()
Properties
- direction → String
-
returns the direction of traversal of the cursor (set using
ObjectStore.openCursor for example).
no setter
- hashCode → int
-
The hash code for this object.
no setterinherited
- key → Object
-
returns the key for the record at the cursor's position. If the cursor is
outside its range, this is set to undefined. The cursor's key can be
any data type
no setter
- primaryKey → Object
-
returns the cursor's current effective key. If the cursor is currently
being iterated or has iterated outside its range, this is set to undefined.
The cursor's primary key can be any data type.
no setter
- runtimeType → Type
-
A representation of the runtime type of the object.
no setterinherited
Methods
-
advance(
int count) → void - sets the number times a cursor should move its position forward.
-
delete(
) → Future< void> - deletes the record at the cursor's position, without changing the cursor's position. Once the record is deleted, the cursor's value is set to null.
-
next(
) → void - advances the cursor to the next position along its direction, to the item whose key matches the optional key parameter. If no key is specified, the cursor advances to the immediate next position, based on the its direction.
-
noSuchMethod(
Invocation invocation) → dynamic -
Invoked when a nonexistent method or property is accessed.
inherited
-
toString(
) → String -
A string representation of this object.
inherited
-
update(
Object value) → Future< void> - updates the value at the current position of the cursor in the object store. If the cursor points to a record that has just been deleted, a new record is created.
Operators
-
operator ==(
Object other) → bool -
The equality operator.
inherited