D++ (DPP)
C++ Discord API Bot Library
Modal Dialog Interactions

Modal dialog interactions are a new Discord API feature that allow you to have pop-up windows which prompt the user to input information. Once the user has filled in this information, your program will receive an on_form_submit event which will contain the data which was input. You must use a slash command interaction response to submit your modal form data to Discord, via the on_slashcommand event. From here calling the dialog method of the interaction_create_t event object will trigger the dialog to appear.

Each dialog box may have up to five rows of input fields. The example below demonstrates a simple setup with just one text input:

#include <dpp/dpp.h>
#include <iostream>
int main(int argc, char const *argv[])
dpp::cluster bot("token");
bot.on_ready([&](const dpp::ready_t & event) {
if (dpp::run_once<struct register_bot_commands>()) {
/* Create a slash command and register it as a global command */
bot.global_command_create(dpp::slashcommand("dialog", "Make a modal dialog box", bot.me.id));
bot.on_slashcommand([&bot](const dpp::slashcommand_t & event) {
/* Check for our /dialog command */
if (event.command.get_command_name() == "dialog") {
/* Instantiate an interaction_modal_response object */
dpp::interaction_modal_response modal("my_modal", "Please enter stuff");
/* Add a text component */
set_label("Type rammel").
/* Trigger the dialog box. All dialog boxes are ephemeral */
/* This event handles form submission for the modal dialog we create above */
bot.on_form_submit([&](const dpp::form_submit_t & event) {
/* For this simple example we know the first element of the first row ([0][0]) is value type string.
* In the real world it may not be safe to make such assumptions!
std::string v = std::get<std::string>(event.components[0].components[0].value);
m.set_content("You entered: " + v).set_flags(dpp::m_ephemeral);
/* Emit a reply. Form submission is still an interaction and must generate some form of reply! */
/* Start bot */
return 0;
The cluster class represents a group of shards and a command queue for sending and receiving commands...
Definition: cluster.h:271
std::string get_command_name() const
Get the command name for a command interaction.
Represents an application command, created by your bot either globally, or on a guild.
Definition: appcommand.h:826
std::function< void(const dpp::log_t &)> DPP_EXPORT cout_logger()
Get a default logger that outputs to std::cout. e.g.
@ m_ephemeral
this message is only visible to the user who invoked the Interaction
Definition: message.h:955
@ st_wait
Wait forever on a condition variable. The cluster will spawn threads for each shard and start() will ...
Definition: cluster.h:254
Definition: dispatcher.h:536
std::vector< component > components
Message components for form reply.
Definition: dispatcher.h:557
interaction command
command interaction
Definition: dispatcher.h:488
Represents messages sent and received on Discord.
Definition: message.h:1103
message & set_content(const std::string &c)
Set the message content.
message & set_flags(uint8_t f)
Set the flags.
Session ready.
Definition: dispatcher.h:783
User has issued a slash command.
Definition: dispatcher.h:499

If you compile and run this program and wait for the global command to register, typing /dialog will present you with a dialog box like the one below:

D++ Library version 10.0.16D++ Library version 10.0.15D++ Library version 10.0.14D++ Library version 10.0.13D++ Library version 10.0.12D++ Library version 10.0.11D++ Library version 10.0.10D++ Library version 10.0.9D++ Library version 10.0.8D++ Library version 10.0.7D++ Library version 10.0.6D++ Library version 10.0.5D++ Library version 10.0.4D++ Library version 10.0.3D++ Library version 10.0.2D++ Library version 10.0.1D++ Library version 10.0.0D++ Library version 9.0.19D++ Library version 9.0.18D++ Library version 9.0.17D++ Library version 9.0.16D++ Library version 9.0.15D++ Library version 9.0.14D++ Library version 9.0.13D++ Library version 9.0.12D++ Library version 9.0.11D++ Library version 9.0.10D++ Library version 9.0.9D++ Library version 9.0.8D++ Library version 9.0.7D++ Library version 9.0.6D++ Library version 9.0.5D++ Library version 9.0.4D++ Library version 9.0.3D++ Library version 9.0.2D++ Library version 9.0.1D++ Library version 9.0.0D++ Library version 1.0.2D++ Library version 1.0.1D++ Library version 1.0.0