Overview
MessageHandler is an abstract base class for handlers that process message updates. This handler is triggered when users send messages in chats and provides convenient methods for sending replies and responses.
Attribute
[MessageHandler(importance: 0)]
The importance level of the handler. Higher values are executed first.
Base Class
public abstract class MessageHandler : AbstractUpdateHandler<Message>
AbstractUpdateHandler<Message> with UpdateType.Message.
Properties
The following properties are inherited from AbstractUpdateHandler<Message>:
Container
IHandlerContainer<Message>
Handler container for the current update.
Telegram Bot client associated with the current container.
The Telegram update being handled.
Additional data associated with the handler execution.
List of successfully passed filters.
Provider for awaiting asynchronous operations.
Methods
Execute
public abstract Task<Result> Execute(
IHandlerContainer<Message> container,
CancellationToken cancellation
)
container
IHandlerContainer<Message>
required
The handler container with message update data.
cancellation
CancellationToken
required
Cancellation token for the operation.
Task<Result> - A result indicating success, fault, or continuation.
Reply
protected async Task<Message> Reply(
string text,
ParseMode parseMode = ParseMode.None,
ReplyMarkup? replyMarkup = null,
LinkPreviewOptions? linkPreviewOptions = null,
int? messageThreadId = null,
IEnumerable<MessageEntity>? entities = null,
bool disableNotification = false,
bool protectContent = false,
string? messageEffectId = null,
string? businessConnectionId = null,
bool allowPaidBroadcast = false,
int? directMessageTopicId = null,
SuggestedPostParameters? suggestedPostParameters = null,
CancellationToken cancellationToken = default
)
The text of the message to send.
parseMode
ParseMode
default:"ParseMode.None"
The parse mode for the message text (None, Markdown, HTML).
The reply markup for the message (keyboard, inline keyboard, etc.).
Options for link preview generation.
The thread ID for forum topics.
Whether to disable notification for the message.
Whether to protect the message content from forwarding.
Task<Message> - The sent message.
Response
protected async Task<Message> Response(
string text,
ParseMode parseMode = ParseMode.None,
ReplyParameters? replyParameters = null,
ReplyMarkup? replyMarkup = null,
LinkPreviewOptions? linkPreviewOptions = null,
int? messageThreadId = null,
IEnumerable<MessageEntity>? entities = null,
bool disableNotification = false,
bool protectContent = false,
string? messageEffectId = null,
string? businessConnectionId = null,
bool allowPaidBroadcast = false,
int? directMessageTopicId = null,
SuggestedPostParameters? suggestedPostParameters = null,
CancellationToken cancellationToken = default
)
The text of the message to send.
parseMode
ParseMode
default:"ParseMode.None"
The parse mode for the message text.
The reply parameters for the message.
The reply markup for the message.
Task<Message> - The sent message.
Example
using Telegrator.Handlers;
using Telegrator.Filters;
using Telegram.Bot.Types.Enums;
[MessageHandler]
[TextFilter("hello")]
public class HelloHandler : MessageHandler
{
public override async Task<Result> Execute(
IHandlerContainer<Message> container,
CancellationToken cancellation)
{
// Reply to the user's message
await Reply(
"Hello! How can I help you today?",
parseMode: ParseMode.Html
);
return Result.Ok();
}
}
BranchingMessageHandler
BranchingMessageHandler is a variant that supports multiple handler methods in a single class, each with its own filters.
public abstract class BranchingMessageHandler : BranchingUpdateHandler<Message>
Example
[MessageHandler]
public class MultiMessageHandler : BranchingMessageHandler
{
[TextFilter("start")]
public async Task<Result> HandleStart()
{
await Reply("Welcome! Let's get started.");
return Result.Ok();
}
[TextFilter("help")]
public async Task<Result> HandleHelp()
{
await Reply("Here are the available commands...");
return Result.Ok();
}
}
See Also