如何检测Discord机器人say命令中用户是否指定了频道？

Let's break down the problem with your current say command code right now: you're always slicing args from index 2 for the message content, regardless of whether the user actually specified a target channel. That means when no channel is provided, you end up cutting off the first word of the intended message.

The Root Problem #

Your original code sets channel to either the mentioned channel, a channel matching args[1], or the current channel—but you never check if that channel was actually found from the user's input before setting msg. So even when the user doesn't specify a channel, msg is still using args.slice(2), which skips the first word incorrectly.

The Solution #

Here's how to adjust your code to properly detect if a channel was specified, and set the message content accordingly:

if(command === `${prefix}say`) { 
  if(!message.member.roles.has(`337402636015894528`)) return; 

  let channel = message.mentions.channels.first() || message.guild.channels.find("name", args[1]);
  let msg;

  // Check if we found a channel from user input
  if(!channel) {
    // No channel specified, use current channel and slice args from index 1
    channel = message.channel;
    msg = args.slice(1).join(" ");
  } else {
    // Channel was specified, slice args from index 2 (skip the channel mention/name)
    msg = args.slice(2).join(" ");
  }

  message.delete();
  channel.send(msg);
}

How This Works #

1. First, attempt to find the target channel: We check for a mentioned channel first, then try to match args[1] to a channel name. If neither works, channel will be undefined.
2. Check if channel exists: If channel is undefined, that means the user didn't specify a valid channel. We fall back to the current channel, and set msg to args.slice(1) (since there's no channel argument to skip).
3. Channel was specified: If we did find a channel from the user's input, we skip that argument (either the mention or the name in args[1]) by slicing from index 2, then join the rest into the message content.

This way, the command behaves exactly as you want:

• When the user types !say #general Hello everyone, it sends "Hello everyone" to #general.
• When the user types !say Hello everyone, it sends "Hello everyone" to the current channel.

内容的提问来源于stack exchange，提问作者Exominem