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Firebase.Database.Query

The Query class (and its subclass, DatabaseReference ) are used for reading data.

Summary

Listeners are attached, and they will be triggered when the corresponding data changes.

Instances of Query are obtained by calling StartAt(), EndAt(), or Limit() on a DatabaseReference.

Inheritance

Direct Known Subclasses:Firebase.Database.DatabaseReference

Properties

ChildAdded
EventHandler< ChildChangedEventArgs >
Event raised when children nodes are added relative to this location.
ChildChanged
EventHandler< ChildChangedEventArgs >
Event raised when children nodes are changed relative to this location.
ChildMoved
EventHandler< ChildChangedEventArgs >
Event raised when children nodes are moved relative to this location.
ChildRemoved
EventHandler< ChildChangedEventArgs >
Event raised when children nodes are removed relative to this location.
Reference
A DatabaseReference to this location
ValueChanged
EventHandler< ValueChangedEventArgs >
Event for changes in the data at this location.

Public functions

EndAt(string value)
Create a query constrained to only return child nodes with a value less than or equal to the given value, using the given orderBy directive or priority as default.
EndAt(double value)
Create a query constrained to only return child nodes with a value less than or equal to the given value, using the given orderBy directive or priority as default.
EndAt(bool value)
Create a query constrained to only return child nodes with a value less than or equal to the given value, using the given orderBy directive or priority as default.
EndAt(string value, string key)
Create a query constrained to only return child nodes with a value less than or equal to the given value, using the given orderBy directive or priority as default, and additionally only child nodes with a key key less than or equal to the given key.
EndAt(double value, string key)
Create a query constrained to only return child nodes with a value less than or equal to the given value, using the given orderBy directive or priority as default, and additionally only child nodes with a key less than or equal to the given key.
EndAt(bool value, string key)
Create a query constrained to only return child nodes with a value less than or equal to the given value, using the given orderBy directive or priority as default, and additionally only child nodes with a key less than or equal to the given key.
EqualTo(string value)
Create a query constrained to only return child nodes with the given value
EqualTo(double value)
Create a query constrained to only return child nodes with the given value
EqualTo(bool value)
Create a query constrained to only return child nodes with the given value.
EqualTo(string value, string key)
Create a query constrained to only return the child node with the given key and value.
EqualTo(double value, string key)
Create a query constrained to only return the child node with the given key and value.
EqualTo(bool value, string key)
Create a query constrained to only return the child node with the given key and value.
GetValueAsync()
KeepSynced(bool keepSynced)
void
By calling keepSynced(true) on a location, the data for that location will automatically be downloaded and kept in sync, even when no listeners are attached for that location.
LimitToFirst(int limit)
Create a query with limit and anchor it to the start of the window
LimitToLast(int limit)
Create a query with limit and anchor it to the end of the window
OrderByChild(string path)
Create a query in which child nodes are ordered by the values of the specified path.
OrderByKey()
Create a query in which child nodes are ordered by their keys.
OrderByPriority()
Create a query in which child nodes are ordered by their priorities.
OrderByValue()
Create a query in which nodes are ordered by their value
StartAt(string value)
Create a query constrained to only return child nodes with a value greater than or equal to the given value, using the given orderBy directive or priority as default.
StartAt(double value)
Create a query constrained to only return child nodes with a value greater than or equal to the given value, using the given orderBy directive or priority as default.
StartAt(bool value)
Create a query constrained to only return child nodes with a value greater than or equal to the given value, using the given orderBy directive or priority as default.
StartAt(string value, string key)