Telegram Message Builder for .NET

Simple message builder for the Telegram.Bot .NET client that simplifies creating messages with styled entities and splitting long messages to comply with Telegram's limits.

🚀 Quick start

Installation:

dotnet add package Telegram.Bot.Messages --version 1.0.4

Example usage:

var builder = new MessageBuilder();
builder.Append("Hello");
builder.AppendBoldLine(", my dear user!");
builder.AppendLine();
builder.AppendParagraph("🧙 Styled entities", (MessageBuilder printer) => {
    printer.AppendField("1", value => value.AppendBold("Bold text"));
    printer.AppendField("2", value => value.AppendItalic("Italic text"));
    printer.AppendField("3", value => value.AppendUnderlined("Underlined text"));
    printer.AppendField("4", value => value.AppendStrikethrough("Strikethrough text"));
    printer.AppendField("5", value => value.AppendCode("Code text"));
    printer.AppendField("6", value => value.Append("Preformatted text").AppendPreformatted("Hey"));
});
builder.AppendLine("C#");
builder.AppendPreformattedLine("var result = 4 + 4;", "csharp");
builder.AppendLine();
builder.AppendLink("Click to link!", new Uri("https://google.com"));
builder.AppendLine();

var message = builder.Build();

// send message with styled entities
await bot.SendMessage(chatId, message.Content, entities: message.Entities);

// for long messages: split by paragraphs (handles text+attachments)
var slices = builder.Build(MessageSplitStrategy.Paragraph, MessageContentType.TextWithAttachments);
foreach (var message in slices) {
    await bot.SendMessage(chatId, message.Content, entities: message.Entities);
}

📚 Features

✅ Supported entities

Message entity	State
Bold	✅ Supported
Italic	✅ Supported
Code	✅ Supported
Strike	✅ Supported
Underline	✅ Supported
Preformatted text	✅ Supported
Mention user name	⏳ Not supported
Custom emoji	⏳ Not supported

📏 Message Splitting

Easily split long messages using different strategies

Split strategy	Description
By word	Splits at word boundaries
By line	Splits at line breaks
By paragraph	Splits between paragraph

⚠️ Size Limitations

Telegram enforces different limits based on message type:

Message Type	Character Limit
With attachments	1024
Text-only messages	4096

Specify MessageContentType when splitting:

var slices = builder.Build(
    MessageSplitStrategy.Paragraph, 
    MessageContentType.TextWithAttachments
);

🛠️ API Reference

Core Methods

MessageBuilder Append(char symbol)
MessageBuilder Append(MessageBuilder builder)
MessageBuilder AppendLine()
MessageBuilder AppendLine(string text)

MessageBuilder AppendBold(string text, bool nl = false)
MessageBuilder AppendBoldLine(string text)

MessageBuilder AppendItalic(string text, bool nl = false)
MessageBuilder AppendItalicLine(string text)

MessageBuilder AppendUnderlined(string text, bool nl = false)
MessageBuilder AppendUnderlinedLine(string text)

MessageBuilder AppendStrikethrough(string text, bool nl = false)
MessageBuilder AppendStrikethroughLine(string text)

MessageBuilder AppendPreformatted(string text, string? lang = null, bool nl = false)
MessageBuilder AppendPreformattedLine(string text, string? lang = null)

MessageBuilder AppendCode(string code, bool nl = false)
MessageBuilder AppendCodeLine(string code, bool nl = false)

MessageBuilder AppendLink(string label, Uri uri, bool nl = false) 
MessageBuilder AppendLinkLine(string label, Uri uri)

MessageBuilder AppendField(string name, string value, bool nl = true, bool boldTitle = false)
MessageBuilder AppendField(string name, Action<MessageBuilder> printer, bool nl = true, bool boldTitle = false)

MessageBuilder AppendParagraph(Action<MessageBuilder> printer, bool nl = true)
MessageBuilder AppendParagraph(string? title, Action<MessageBuilder> printer, bool nl = true, bool boldTitle = false)

MessageBuilder TrimEnd()

MessageSlice Build()
MessageSlice[] Build(MessageSplitStrategy splitStrategy, MessageContentType contentType)

🛠️ Contribution

We welcome contributions! Please feel free to:

• Report bugs 🐛
• Suggest features 💡
• Submit pull requests 🔄