cursor

cursor

The cursor function opens a cursor for retrieving data out of the indexeddb database.

Parameters

• source:
  • An object store, an object store promise object, an index or an index promise object
• range
  • A filter for narowing the results. See keyRange for more information
  • Optional
    • Default: keyRange.lowerBoud(0)
• Direction
  • The direction the cursor must move trough the results. See w3 for more information.
  • Optional
    • Default: undefined

Returns

The function returns a promise object with 3 callbacks

• Success callback
  • The object were retrieved successfully
  • The first argument contains an array with all objects that match the given filter.
    • data
    • key
  • The second argument contains the transaction.
  • The third argument contains the original indexeddb event arguments
• Error callback
  • Retrieving data failed
  • The argument object contains a custom error object.
• Progress callback
  • Called every time an object matches the given filter
  • The first argument contains an object with the data and possible operations on the data
    • data
      • contains the retrieved object
    • key
      • contains the primary key of the object
    • skip
      • function that skips a given number of results
      • skip(5)
    • update
      • function that updates the current object with the given object
      • update({})
    • remove
      • function that removes the current object
      • remove()
  • The second argument contains the result object
  • The third argument contains the original indexeddb event arguments

Errors

• DataError
  • The provided range parameter isn't a valid key or key range.
• TransactionInactiveError
  • You are trying to open a cursor outside or on an inactive transaction.
• TypeError
  • The provided directory parameter is invalid.
• InvalidStateError
  • You are trying to modify data on a removed object store.

skip method

• DataError
  • The provided range parameter isn't a valid key or key range.
• TypeError
  • The provided count parameter is zero or a negative number.
• InvalidStateError
  • You are trying to skip data on a removed object store.

update method

• DataError
  • The underlying object store uses in-line keys and the property in value at the object store's key path does not match the key in this cursor's position.
• ReadOnlyError
  • You are trying to update data in a readonly transaction.
• TransactionInactiveError
  • You are trying to update data outside or on an inactive transaction.
• DataCloneError
  • The data you are trying to update could not be cloned. Your data probably contains a function which can not be cloned by default. Try using the serialize method to update the data.
• InvalidStateError
  • You are trying to update data on a removed object store.

remove method

• ReadOnlyError
  • You are trying to remove data in a readonly transaction.
• TransactionInactiveError
  • You are trying to delete data outside or on an inactive transaction.
• InvalidStateError
  • You are trying to remove data on a removed object store.

Example

{{ var dbpromise = linq2indexedDB.core.db("name", 1); var transactionPromise = linq2indexedDB.core.transaction(dbpromise, "objectstore"); var objectStorePromise = linq2indexedDB.core.objectStore(transactionPromise, "objectstore"); linq2indexedDB.core.cursor(objectStorePromise).then(success, error, progress); function success(args){ var data = args0; // Array of objects {data: {}, key: 1 } var transaction= args1; var orignalevent = args2; } function error(args){ var error= args; } function progress(args){ var data = args0; // Single object {data: {}, key: 1, skip: function (number){}, update: function(obj){}, remove: function(){} } var result= args1; var orignalevent = args2; } }}