The MatchExpression class represents a matching expression used to compare custom variables or predefined properties when searching for users or Rooms.
Namespace: Sfs2X.Entities.MatchAssembly: SmartFox2X
(in SmartFox2X.dll) Version: 220.127.116.11 (1.7.0)
public class MatchExpression
The following example shows how to create a simple matching expression made of two concatenated conditions: it compares the custom "rank" and "country"
User Variables to the passed values. This expression could be used during the creation of a Game Room, to filter the users that the server should take
into account when sending the invitations to join the game (only italian users with a ranking greater than 5 - whatever this number means to our game):
MatchExpression exp = new MatchExpression('rank', NumberMatch.GREATER_THAN, 5).And('country', StringMatch.EQUALS, 'Italy');
The following example creates a matching expression made of three concatenated conditions which compare two predefined Room properties and the custom "isGameStarted"
Room Variable to the passed values; this expression could be used to retrieve all the Game Rooms still waiting for players to join them:
MatchExpression exp = new MatchExpression(RoomProperties.IS_GAME, BoolMatch.EQUALS, true)
.And(RoomProperties.HAS_FREE_PLAYER_SLOTS, BoolMatch.EQUALS, true)
.And("isGameStarted", BoolMatch.EQUALS, false);
The following example creates a matching expression which compares a nested property in a complex data structure; an SFSObject called "avatarData" (could be a User Variable for example)
contains the "shield" object (a nested SFSObject) which in turn contains, among others, the "inUse" property which could be used to retrieve all user
whose avatars are currently equipped with a shield:
MatchExpression exp = new MatchExpression("avatarData.shield.inUse", BoolMatch.EQUALS, true);
The following example is similar to the previous one, but it involves an SFSArray. The "avatarData" object contains the "weapons" SFSArray, from which the expression retrieves
the third element (that .3 means "give me the element at index == 3") that we know being the weapon the user avatar has in his right hand. Again, this element is an SFSObject containing,
among the others, the "name" property which can be compared to the passed string. This example could be used to retrieve all users whose avatars have the Narsil sword in the right hand:
MatchExpression exp = new MatchExpression("avatarData.weapons.3.name", StringMatch.EQUALS, "Narsil");