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Update Group

In other words, as a group owner, how can I update the group details? You can update the existing details of the group using the updateGroup() method. 
var GUID = "GUID";
var groupName = "Hello Group";
var groupType = CometChat.GROUP_TYPE.PUBLIC;
var group = new CometChat.Group(GUID, groupName, groupType);

CometChat.updateGroup(group).then(
group => {
  console.log("Groups details updated successfully:", group);
}, error => {
  console.log("Group details update failed with exception:", error);
}
);
This method takes an instance of the Group class as a parameter which should contain the data that you wish to update.
ParameterDescription
groupan instance of class Group
After a successful update of the group, you will receive an instance of Group class containing update information of the group. For more information on the Group class, please check here